<p class='jove_content'>This work was supported by the National Institute on Alcohol Abuse and Alcoholism (RO1 AA014925 awarded to Dr. Patricia H. Janak at University of California, San Francisco, CA, USA), Fonds de recherche du Quebec &#8211; Sant&#233; (NC) and the Natural Sciences and Engineering Research Council (NC, 387224-2010). The open-access publication of this article was made possible by sponsorship from Med Associates Inc. </p>

<p class="jove_content"> Tüm prosedürler Concordia Üniversitesi Hayvan Araştırmaları Etik Komitesi tarafından onaylanmış ve Hayvan Bakımı Kanada Konseyi önerileri ile hemfikir edilir. </p><p class="jove_title"> 1. Hayvanlar </p><ol><li> (- Varışta 240 gr 220) erkek Long-Evans sıçan edinin. </li><li> 07:00 ışıklar olan bir 12 saatlik bir ışık-karanlık döngüsünde bir sıcaklıkta (21 ° C) ve nem (% 44) kontrollü hayvan bakım tesisi fareleri üzerinde muhafaza edin. </li><li> Girişte Pair-ev fareleri. 3 gün sonra, ayrı ayrı p-çip yatak, bir naylon kemik ve standart sıçan yemi ve suya serbest erişim ile plastik ayakkabı kutusu kafeslere ev fareler. Su şişesinin ek olarak, ikinci bir şişe sonraki yerleştirilmesine izin vermek için iki çevirme kenarı olan kafes kapaklarını kullanın. NOT: Ayrı kısa sürede hayvan bakım tesisi geldikçe Rats muhafaza edilebilir. </li><li> Günlük sıçan işlemek için başlayın. NOT: Bir rehber olarak, elleçleme bir hafta pi olmanın onları ACCLIMATE genellikle yeterlidircked kadar ve deneyci tarafından ele. </li></ol><p class="jove_title"> Ana Cage 2. Aralıklı Etanol Erişim </p><p class="jove_content"> NOT: evde kafes içinde Davranış aralıklı etanol erişimi sıçanlar deney davranışsal eğitim safhası <sup>17-19</sup> başlamadan önce etanol fizyolojik önemli miktarlarda içecek sağlamak için. Bu açık ya da koyu çevrimi esnasında herhangi bir zamanda başlatılabilir, ancak aydınlık evresi sırasında bu prosedürü başlatın. </p><ol><li> Her bir sıçan için, iki şişe hazırlayın. <ol><li> 100 ml plastik etanol şişe ve 473 ml standart plastik su şişesi gibi dereceli silindir kullanın. Nedeniyle sızıntı ve buharlaşma etanol kaybını en aza indirmek için, neredeyse maksimum hacim kapasitesi dolu bir nispeten küçük kapasiteli etanol şişe kullanın. </li><li> Musluk suyu içinde% 95 lik etanol seyreltilmesi,% 15 etanol ile bir doldurunuz. Not: diğer etanol konsantrasyonları, örneğin% 10 veya% 20,% 15 etanol yerine kullanılabilmektedir. </li><li> Fimusluk suyu ile ikinci şişe ll. </li><li> Her şişeye, sızıntıyı en aza indirmek için bir bilye yatağı içeren bir siper tüp ile bir lastik tıpa takın. </li></ol></li><li> Kontrol kafesleri sıçan ya da yatak içermeyen haricinde ev kafesleri aynı tedavi edilen iki kontrol kafesleri, ayarlayın. <ol><li> 2.1.4 - adımlarla 2.1.1 belirtildiği gibi kontrol kafesleri için etanol ve su şişeleri hazırlayın. </li><li> (- 2.8.2 2.8.1 adımda tarif edildiği gibi), etanol ile erişim oturumu boyunca oluşabilecek dökülmesi ve / veya buharlaştırma için kontrol etmek için kontrol kafeslerinden edilen yöntemleri kullanınız. </li></ol></li><li> Tüm etanol ve su şişeleri tartılır. Bütün ağırlıkları kaydedilir. </li><li> Tüm fareler tartılır. Bütün ağırlıkları kaydedilir. </li><li> Etanol şişe ve her ana kafesindeki su şişesi yerleştirin ve aynı zamanda kafes kontrol eder. 24 saat boyunca kafeslerde her iki şişe bırakın. </li><li> 24 saatlik bir süre sonunda, her iki şişe kaldırmaaynı zamanda kafes. </li><li> Tüm etanol ve su şişeleri tartılır. Bütün ağırlıkları kaydedilir. </li><li> Bu 24 saat önce, her bir sıçan için kafese yerleştirildi zaman şişenin ağırlığı kafese bertaraf edildikten sonra 24 saatlik bir süre boyunca tüketilen ne kadar etanol ve su belirlemek için, her şişenin ağırlığının çıkartılması. <ol><li> Iki kontrol kafesler için aynı yapın ve ardından her akışkan için dökülme ortalama miktarını hesaplamak. </li><li> Her bir sıçan için karşılık gelen etanol ve su tüketimi önlemlerden, sırasıyla bir etanol ve su dökülmesi, ortalama miktarını çıkarın. </li><li> G / kg su tüketimi ve etanol tercih etanol tüketimi hesaplamak için bu dökülme kontrol fark yöntemleri kullanınız. </li></ol></li><li> Etanol tüketimi (g / kg), ilk olarak toplam çözeltinin (etanol + su bileşenler) yoğunluğuna dayalı olarak, hacim (mi) içine tüketilen etanol çözeltisi ağırlığını (g) dönüştürmek hesaplamak için, uygunFormül Hacmi (mi) = Ağırlığı (g) / Yoğunluk (g / ml) eklenmiştir. Not: çözeltisinin yoğunluğu etanol konsantrasyonunun bir fonksiyonu olarak değişir. <ol><li> Daha sonra, tüketilen ağırlığı (g), etanol içinde elde etmek için kullanılan belirli bir yüzdesi bir çözüm için ölçekli etanol yoğunluğu (g / ml) tarafından kullanılan, etanol çözeltisi hacmi (mi) çarpar. </li><li> Etanol tüketimi g / kg ölçümünün elde edilmesi için, sıçan ağırlığına (kg) tarafından kullanılan, etanol ağırlığı (g) bölün. </li></ol></li><li> Etanol tercih hesaplamak için, toplam sıvı (etanol + su, mi) alımının bir yüzdesi olarak etanol miktarı (mi) ifade etmektedir. </li><li> Sıçan ev kafesine sadece geri su şişesi getirin. Sonraki 24 saat, suya fareler erişim vermek ama etanole değil. Bunun yerine, bir etanol şişe, ev kafes üzerine ağırlığı önceden tartılmış olan ikinci su şişesi yerleştirin. </li><li> 24 saatlik bir süre sonunda, aynı zamanda kafes hem de su şişeleri çıkarın. </li><li> Su şişeleri her iki seti de tartılır. Kaydedin tüm weights. </li><li> Bu adımda 2.8.1 tarif edildiği gibi kontrol kafeslerinden elde edilen ortalama dökülme ölçü çıkartılmasıyla, 24 saat önce kafese yerleştirildi zaman şişenin ağırlığı kafese bertaraf edildikten sonra, her şişenin ağırlığının çıkartılması - 2.8.2. </li><li> Su tüketimini hesaplamak için bu dökülme kontrollü fark önlemleri kullanın. </li><li> 2,14 adımda 2.1 de tarif edildiği gibi, farelere etanol ve su şişeleri sağlamak suretiyle yeniden çevrimi başlar. <ol><li> Etanol tüketimi, yüksek ve istikrarlı seviyelerini ikna etmek için birden çok (yaklaşık 12) oturumları bu döngüyü tekrarlayın. Ev kafesinde etanol kullanımı için temsili sonuçlar (g / kg) için <strong>Şekil 1&#39;e bakınız.</strong> </li><li> Bir yan tercih gelişimini önlemek için oturumlar boyunca kafes kapağındaki etanol ve su şişesi uzaysal pozisyonu geçiş yapma. </li><li> Karşısında doğru ve istikrarlı etanol konsantrasyonunu sağlamak için haftada bir kez taze etanol çözüm olunoturumları. Bu yaklaşımı kullanarak, uzun süreli dönemler boyunca etanol buharlaşma etkisini en aza indirmek. </li></ol></li></ol><p class="jove_title"> 3. Aparatlar </p><ol><li> Bir havalandırmalı, ses azaltıcı kabini içindeki ev, her klima odası. </li><li> Her klima paslanmaz çelik metal çubuk zemin odasını, şeffaf polikarbonat tavan, açık polikarbonat arka duvar ve ön kapı ve alüminyum metal paneli yanaklar Construct. <ol><li> Merkezi sağ, metal yan duvarın tabanına yakın bir sıvı portu takın. Portuna girdilerini algılamak için kızılötesi fotosel ile sıvı noktasına giriş donatmak. </li><li> Bir küt uçlu bir iğne kullanılarak etanol içeren bir 20 ml şırınga ve sıvı giriş arkasından polietilen boru bağlayın. Ses azaltıcı hücre dışında bulunan bir şırınga pompa içine şırınga yerleştirin. Pavlovyan ayrımcılık eğitim oturumları için, pompa içine yerleştirmeden önce şırıngaya etanol yükleyin. Başbakan boru by el pompası ilerleyen ve sonra akışkan bağlantı noktasından fazla etanol silin. </li><li> Sol yan duvar üzerinde, bölmenin tavanına yakın merkezi beyaz houselight gerekmektedir. </li><li> Bir tıkırtı (2 Hz devir) ve sol yan duvarın sol üst köşesinde hoparlör ile bir beyaz gürültü jeneratör yükleyin. </li></ol></li><li> Farklı bir bağlam yaratmak için görsel, koku alma, ve dokunsal uyarılara belirli bir yapılandırma ile her klima odasına kıyafeti. <ol><li> İki farklı bağlamlar, Bağlam 1 ve Bağlam 2 gibi diğer yarısı olarak klima odalarının belirlenmiş Bağlam 1 ve Bağlam 2. Yapılandırma yarısını kullanın. </li><li> Bir Petri kabı içine siyah karton tavan ve ön panel üzerinde ve arka odasının duvarları, (musluk suyunda seyrelterek limon yağı ile yapılan% 10 v / v) sprey limon kokusu yerleştirmek ve ortasına yerleştirin onu, Bağlam oluşturmak için 1 odasının zemininin altında bir metal atık tepsi ve metal r üzerinde şeffaf polikarbonat zemin panelini takınod kat. Emici kağıt havlu veya tezgah liner ile atık kasetini sıralanıyor. </li><li> Bağlam 2 oluşturmak için, onlar açık ki, bir Petri kabı içine (musluk suyunda benzaldehitin seyreltilmesi% 10 v / v) badem koku sprey ve merkezi olarak yerleştirin, ortaya odasının tavan ve ön ve arka duvarları bırakın odasının tabanına altında bir metal atık tepsi, ve bahsedilen metal çubuk, zemin üzerinde bir delikli metal bir taban paneli yerleştirin. Emici kağıt havlu veya tezgah liner ile atık kasetini sıralanıyor. </li></ol></li></ol><p class="jove_title"> 4. Alışma </p><p class="jove_content"> Davranışsal eğitim odası fareleri alışmakta ve iklimlendirme odası içinde iki bağlamda her. Deneyin bu aşaması için, 20 ml şırınga içine etanol yüklemeyin. </p><ol><li> Iki kısa alışkanlık seansta laboratuvarda davranışsal eğitim odası hayvan bakım tesisi taşınan olma sürecine fareleri alıştırmak. <ol><li> İlk oturumda, sıçan yüklemek in evlerine hayvan bakım tesisi bir tekerlekli arabası üzerine kafesleri ve laboratuvarda davranışsal eğitim odası taşırlar. , Oda ışıkları yanar her ses zayıflatıcı kabinler hayranları açın, oda çıkmak, kapıyı kapatın ve arabası üzerinde evlerinde kafeslerde kalan süre sıçanlar, 20 dakika boyunca bu yeni ortama uyum sağlar. Bu 20 dakikalık sürenin sonunda, hayvan bakım tesisi için fareleri döner. </li><li> İkinci oturumda, laboratuvarda davranışsal eğitim odası fareleri getirmek. Daha önce olduğu gibi, odadaki ışıkları ve kabinler hayranlarını bırakın. Kapı dağılmasını en aza indirmek için kapalı, odada kalır ve idare ve davranışsal eğitim odasında her sıçan tartın. Ağırlıkları kaydedin ve sonra hayvan bakım tesisi için fareleri dönmek. </li></ol></li><li> Iki kısa alışkanlık seansta klima odalarına fareleri alıştırmak. <ol><li> , Davranışsal eğitim odası sıçan taşıyın her rat ağırlığını kaydetmek,ve belirlenen iyileştirme odasının içine, her sıçan yükleyin. </li><li> İlk alışma oturumda yarım Bağlamında 1 olarak odaları ve Bağlamında 2 akçeye kadar ayarlayın. </li><li> İkinci alışkanlık oturumda önceki oturumda kullanılan değildi bağlamda her odasını kurmak. </li><li> , Farelerin yarısı bu tür ideal bir birinci doğrultuda 1. ardından ilk Bağlam 2 maruz Bağlam 2 ve diğer yarısı, ardından Bağlam 1 maruz kaldığı, bir denge şekilde alışkanlık oturumları yürütmek hem alışkanlık oturumları yürütmek Gerekirse iki gün yayılabilir rağmen aynı gün,. </li><li> Alışma oturumları için, programın verildikten sonra houselight 1 dk aydınlatmak için bir bilgisayar programı kullanmak. 20 dakikalık bir süre boyunca yapılan akışkan ağzı girdilerinin sayısı kaydedilir. Oturumun sonunda, kapatmak için houselight programlamak. Alışma oturumları sırasında herhangi etanol veya ipuçlarını sunmak etmeyin. </li></ol></li&gt; <li> , Odalarından fareleri kaldır evlerinde kafeslerde onları geri ve hayvan bakım tesisi onları geri taşıma. </li><li> Ekipmanları <em>(örneğin,</em> zemin panelleri, atık tepsiler, petri) temizleyin. Daha fazla ayrıntı için adım 5.7 bakınız. </li></ol><p class="jove_title"> 5. Pavlovyan Ayrımcılık Eğitimi (PDT) </p><p class="jove_content"> Davranışsal tren sıçan etanol ve olmayan bir ikinci işitsel işaret ile eşleştirilmiş bir işitsel işaret arasındaki ayrım. Deneyin bu safhası için,% 15 etanol ile, 20 ml şırınga doldurun. </p><ol><li> 3.3.2 ve 3.3.3 adımda tarif edildiği gibi, farklı bir bağlam oluşturmak için görsel, koku alma bölgesinin özel konfigürasyonu ve uyaranı her iyileştirme odası kıyafet <ol><li> Etanol tüketimi ve tercihinize göre, Bağlam 1 ve dengelenmiş biçimde Bağlamında 2 diğer yarısı sıçanların yarısı atama ev kafes etanol erişim prosedürünün son 2 seans arasında ortalama. Devam için başvurunext Bağlam A. NOT olarak PDT sırasında kullanılan: Her sıçan sadece eğitimin bu aşamasında bir bağlam deneyim gerekir. </li><li> Koku uyaran her klima odasına eklenecek son bağlamsal uyaran olduğundan emin olun. Koku uyarıcı ihtiva eden ve farklı koku comingling en aza indirmek için, odacık ve ses zayıflatıcı hücrenin kapıları kapatın. </li></ol></li><li> , Davranışsal eğitim odasına sıçan getirin her rat ağırlığını kaydetmek, ve belirlenen klima odasına her sıçan yükleyin. </li><li> Her PDT oturumu sırasında aşağıdaki olaylar dizisini kontrol bilgisayar programını başlatın. <ol><li> Programından sonra 5 dk verildikten anda, houselight aydınlatmak. </li><li> Beyaz gürültü uyarıcı sunmak ve tıkırtı 16 kez her uyaran. CS + olduğu, bu işitsel uyarımın biri belirler ve diğer iki bağlamlarında bir denge şekilde, CS-için. </li><li> Her CS + ve CS deneme l Yapast 10 sn. </li><li> CS + &#39;nın son 6 sn boyunca sıvı giriş 0.2 ml etanol sağlar. CS- sırasında herhangi etanol teslim etmeyin. </li><li> Her PDT oturumu ortalama son 58 dakika yapın. Bir değişken zaman 67 sn programa CS + ve CS- her sunun. </li><li> 10 sn CS aralık sırasında Tutanak akışkan bağlantı girişleri (CS sunum sırasında 10 sn), 10 saniye önceden CS aralığı (hemen önce CS başlangıcından 10 sn) ve 10 sn sonrası CS aralığı (hemen 10 sn Aşağıdaki CS CS + ve CS sunumlar yanı sıra tüm oturum için toplam sıvı liman girişleri için) ofset. Ayrıca bu aralıklar sırasında yapılan her liman giriş süresini kaydedebilirsiniz. </li><li> Oturum sonunda, houselight kapatın. </li></ol></li><li> , Odalarından fareleri kaldır evlerinde kafeslerde onları geri ve hayvan bakım tesisi onları geri taşıma. </li><li> Sıçanlar, her biri s PDT teslim etanol 3.2 ml tüketilen sağlamak için sıvı noktalarını kontrolsalgılamanın ardından. </li><li> Küçük bir su miktarını ihtiva eden 60 ml&#39;lik bir şırınga ile polietilen borudan dışarı etanol yıkayın. Daha sonra, kuru olduğundan emin olmak için, ikinci bir boş şınnga kullanılarak, boru içinden havanın 60 mi geçmektedir. </li><li> Ekipmanı temizleyin. Günlük temizlik için, zemin panelleri, atık tepsiler ve Petri bulaşıkları yıkamak. Haftada bir kez, tüm klima odasını temizleyin. Deney aparatı içine istenmeyen kokuları almaktan kaçınması kokulu temizlik ürünleri kullanmayın. </li><li> Sıçanlar CS- vs CS + kendi port girişi yanıtları istikrarlı ayrımcılığı göstermek kadar günlük PDT oturumları devam ediyor. NOT: CS- yanıt olarak yapılan liman girişleri düşük kalmalıdır ise CS + cevaben yapılan Liman girişleri, seans içinde yükselecektir. Gerekli PDT oturumların tam sayısı bir rehber olarak, yaklaşık 20 oturum planı, değişebilir yanıt klimalı ayrımcılık, ama gerçekleştirme olanağı. </li></ol><p class="jove_title"> 6. Extinction </p><ol><li> Her klima cham kıyafetber görsel, koku alma ve dokunma uyaranlara fareler seans FDT sırasında yaşanan birinden farklı bir bağlam yaratmak. Bağlam 1 PDT kullanıldı Örneğin, tükenme oturumları için Bağlamında 2 olarak odasını yapılandırın. Bağlam B olarak nesli sırasında kullanılan bağlamda bakın </li><li> Aynı seans FDT için söndürme oturumları yürütmek, ancak CS + sırasında herhangi etanol teslim yok. <ol><li> CS + ve CS- sunmak için PDT sırasında kullanılan aynı bilgisayar programını kullanın. </li><li> Deneyin aşamalarında genelinde tutarlılığı korumak için, şırınga pompası içine boş bir şırınga yüklemek ve pompa açık bırakın. Polietilen boru tükenme oturumlardan önce etanol içermediğinden emin olun. </li></ol></li><li> Sıçanlar artık gösteri CS + ve CS- arasındaki yanıt ayrımcılığa kadar günlük söndürme oturumları devam ediyor. NOT: differe kalmayıncaya kadar CS + cevaben yapılan Liman girişleri giderek, söndürme oturumlar boyunca azalma olmalıdırCS- yanıt olarak yapılan CS + yanıt olarak yapılan liman girişleri ve liman girişleri arasında nce. Değişebilir yanıt klimalı, ama bir rehber olarak, yaklaşık 8 oturum planı söndürür için gerekli nesli oturumların tam sayısı. </li><li> Adım 5.7 &#39;de tarif edildiği gibi, her bir oturumun sonundaki ekipmanı temizleyin. </li></ol><p class="jove_title"> 7. Bağlam kaynaklı Yenileme Testi </p><ol><li> PDT oturumları sırasında yaşandı bağlamını oluşturmak için görsel, koku alma ve dokunma uyaranları her klima odasına donatın. Örneğin, belirli bir sıçan seans FDT Bağlam 1 yaşıyorsanız, test bölümünde Bağlamında 1 olarak onun odasını yapılandırın. Bağlam A olarak yenileme testi sırasında kullanılan bağlamda bakın </li><li> Aynı seans FDT için bağlam-kaynaklı yenileme testi yapmak, ancak yenileme testi sırasında herhangi etanol teslim yok. Günümüze <br /> Etanol kesintisi CS + ve PDT oturumları sırasında daha önce olduğu gibi CS, ama. <ol><li> Aynı bilgisayar pr kullanınCS + ve CS- sunmak için PDT sırasında kullanılan PROGRAM ÇA Ğ RISI. </li><li> , Fazlar arasında tutarlılığı sağlamak şırınga pompası içine boş bir şırınga yüklemek ve bırakmak için pompa döndü. Polietilen boru test oturumu önce etanol içermediğinden emin olun. </li></ol></li><li> Pavlovyan klimalı alkol-arama davranışının bağlam kaynaklı yenileme gözlemleyin. NOT: Bu yenilenme CS + &#39;ya ve CS- göre CS-, yanıt olarak yapılan liman giriş davranışlarında bir değişiklik, CS +&#39; ya karşılık olarak yapılan bağlantı girişlerin sayısı içerisinde olan selektif bir artış ile daha anlaşılır olacaktır gözlenen yanıt vermenin söndürme eğitimi sonu. </li><li> Adım 5.7 &#39;de tarif edildiği gibi, oturumun sonundaki ekipmanı temizleyin. </li></ol>

<ol>
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<p class="jove_content"> Tüm deneysel prosedürleri Concordia Üniversitesi Hayvan Araştırmaları Etik Kurulu tarafından onaylanmış ve Hayvan Bakımı Kanada Konseyi kurallarına uygundur edildi. <span style="font-size: 14px; line-height: 28px;">Bu makalenin açık erişim yayın Med Associates Inc sponsorluğunda ile mümkün olmuştur</span> </p>

<p class="jove_content"> Bu prosedürün sonuçları rutin alkol teslimatı eşlik ayrık çevresel uyaranlar alkol arama davranışını sürücü kapasitesini edinebilirler ortaya koyuyor. Onlar da önce kullanılabilirliği veya alkol olmaması ile ilişkili bağlamsal uyaranlara ayrık alkol-akıllı ipuçlarına davranışsal tepkiler klimalı rehberliği olduğunu göstermektedir. </p><p class="jove_step"> Protokol çerçevesinde kritik adım </p><p class="jove_content"> Bu görev bağlamları sıçan için dış olan uyaranlara dahil. Ancak, sınavda sıçan interoseptif devlet de yenilenmesini <sup>20</sup> etkileyebilecek bir &#39;bağlam&#39; teşkil edebilir. Bu intrakranial mikroinfüzyonlar veya sistemik enjeksiyonlar gibi, yenileme testi önce ortaya çıkar ve bunların interoseptif durumunu değiştirmek herhangi prosedürlere sıçan alıştırmak için bu nedenle önemlidir. Ayrıca, mikroinfüzyonlar veya sistemik enjeksiyonlar için alışma nesli ve PDT lar hem öncesinde yapılmalıdıressions Deneyin belirli bir fazı ile ilişkili hale gelmesini önlemek için bu yöntemleri. </p><p class="jove_content"> , CS süresi, CS-ABD aralığı ve intertrial aralığı (ITI) gibi zamansal parametreleri, uzun klima paradigmalar <sup>21-26</sup> çeşitli yanıt klimalı etkileyen çeşitli bilinmektedir. Benzer şekilde, zamansal parametreler bizim prosedüründe yenileme etkisi gözlem etkileyebilir. Protokolde belirtilen dışındaki parametrelerin Herhangi bir set deneysel büyük soruşturmalarda bunları istihdam geçmeden önce pilot çalışmalar valide edilmelidir. </p><p class="jove_step"> Değişiklikler ve sorun giderme </p><p class="jove_content"> Önceki araştırmalar, fareler kafes evlerinde tüketmek etanol miktarı <sup>17,27</sup> fareler satın alınan gelen ilgili bir fonksiyonu olarak değişebilir bulmuştur. Tedarikçi nedenle çalışmanın bu aşamasında önemli bir husustur. Aynı şekilde, fare soyunun tercih co olmalıdıretanol tüketimi <sup>28-31</sup> strain farklılıklar çok sayıda rapor var gibi, dikkatli nsidered. </p><p class="jove_content"> Caydırıcı bir klima paradigma önce iş sıçanların gelişimsel yaşı Pavlovyan şartlı korku tepkisi <sup>32</sup> yenilenmesi gözlem etkilediğini göstermiştir. (Doğum sonrası 20 gün daha genç) çok genç sıçanlarda bir yenileme etkisinin olmaması nedeniyle bağlamsal bilgi <sup>33</sup> engelli kodlama olduğu ileri sürülmüştür. Bu prosedür kullanılmak üzere sıçanların gelişimsel yaş bu nedenle dikkate alınmalıdır. </p><p class="jove_content"> 10% <sup>9,16,%</sup> 15 <sup>14, 15</sup> veya% 20 etanol çözeltileri, ev sahibi kafes etanol erişim ve deney PDT aşamalarında kullanıldığı zaman Pavlov kıvamlandırılmış alkol arama davranışının Yenilenme gözlenmiştir. Araştırmacılar, LABORATOR bu prosedür oluşturan amaçları için etanol, bu konsantrasyonlardan herhangi kullanabilirler. </p><p class="jove_content"> Pavlovyan ayrımcılık eğitim edinimi sırasında teslim edildi, tüm etanol tüketilen edilmiştir sağlamak için her seanstan sonra sıvı portları kontrol etmek önemlidir. Ek 10 için klima odalarına sıçan Leaving - Her seanstan sonra 15 dakika oturumu sırasında tüketilen değildi herhangi etanol tüketimini teşvik etmek için erken PDT yapılabilir. PDT ilerledikçe limanlarda unconsumed etanol bırakarak farelerin sayısı düşmelidir. PDT sıçanların sonunda ya ise (a) tüm etanol tüketen değil ve / veya (b) bu ​​denekler çalışmanın düştü gerektiğini daha sonra CS + yanıt vermiyor. En güvenilir bir sıçan CS- daha CS + &#39;ya daha fazla cevap verir. Ancak, bazı fareler böylece ayrımcılık kanıt gösteren değil, hem ipuçlarına yüksek seviyelerde yanıt verebilir. PDT sırasında yüksek CS + ve CS- hem yanıt göstermektedir fareler çalışmadan bırakılır. Bizim tecrübelerimize göre, bu konular dikkat çekici ayrımcılığı gösteriyorPDT sırasında CS- yanıt kendi yüksek düzeyde sıvı giriş etanol varlığı ile tahrik edilir düşündürmektedir etanol yokluğunda birinci söndürme oturumu süresince,. Bu kişiler de sağlam yenileme etkilerini gösterme eğilimindedir. </p><p class="jove_step"> Prosedürün Sınırlamalar </p><p class="jove_content"> Yenileme Test etanol yokluğunda yürütülür için, CS + ile ortaya çıkarılan durumunu bağlantı girişleri yavaş yavaş test oturumu boyunca azalır. Bu nedenle, davranış toplam miktarı deneysel olarak ortaya çıkan değişiklikler değerlendirilebildiği karşı test üretilen oldukça düşüktür. Yanıt bu görevde test seansı sonunda karşı başlangıcında daha yüksek olma eğilimindedir, çünkü bir deneme-by-deneme olarak yanıt koşullanmış üzerinde deneysel manipülasyon etkilerini incelemek önemlidir. </p><p class="jove_content"> Sıvı prize Yazılar bu görevi ana bağımlı ölçüsünü sunar. Ancak, hatalı bir port girişi regi olabilirbir hayvan visker sıvı giriş açıklığına karşı gelen kızılötesi ışın kırmak için sıvı haznesine yakın olup olmadığını stered. Seyrek, hatalı yanıtlar ortada iken, toplam liman dramatik bir artış önceki oturumlarında deneğin davranışları göreceli girişleri gibi. Hayvanları videoya olası hatalı tepkilerin saptanmasını kolaylaştırmak, eğitim ve test boyunca fareler tarafından sergilenen davranışların bir daha rafine analizi için olanak sağlayacak. </p><p class="jove_step"> Mevcut / alternatif yöntemlere göre tekniğin önemi </p><p class="jove_content"> Ilaç-arama davranışının Bağlam-kaynaklı yenileme büyük ölçüde böyle bir kolu basın <sup>8,34</sup> veya burun <sup>12</sup> poke olarak birincil bağımlı değişken bir operant yanıt olduğu enstrümantal bir klima görevi kullanılarak incelenmiştir. Bu prosedürde, ilaç arama yanıtı sunumları ile ortaya sıvı giriş için &quot;klimalı bir yaklaşım&quot; dirCS +. Bu yanıt muhtemel çevresel uyaranlara ve insanlarda kötüye ilaçların farmakolojik etkileri arasında birliklerin oluşumunu aracılık öğrenme sürecidir Pavlovyan öğrenme yoluyla elde edilir. </p><p class="jove_step"> Gelecek uygulamalar </p><p class="jove_content"> Bu görev, Pavlov durumunu alkol arama davranışının <sup>16</sup> bağlamı kaynaklı yenilenmesine katılan Nöral mekanizmalarını incelemek için Neuropharmacology, optogenetik ve nörokimyasal ile kombinasyon halinde de kullanılabilir. Ayrıca, Pavlovyan klimalı alkol-arama davranışının satın alma ve nesli düzenleyen davranışsal ve nöral mekanizmalar incelenmiştir edilebilir. Son olarak, bu görev, insan addi isteka maruz tedavi sonrası ilaç akıllı işaretlere reaktifliğine çevresel bağlamda ilişkili ilacın etkisini azaltmayı amaçlayan translasyonel araştırma için önemli bir yön yenilenmesini engelleyebilecek tükenme manipülasyonları keşfetmek için kullanılabilircts. </p>

<p class="jove_content"> Ayık kalan alkol kötüye bozukluklardan muzdarip bireylerin karşılaştığı önemli bir sorundur. Yoksunluk, Pavlovyan koşullama yoluyla, sarhos¸luk <sup>1,2</sup> ile ilişkili hale gelebilir rutin alkol kullanımı eşlik çevresel uyarıcıların, davranışsal, psikolojik ve fizyolojik etkisi açığı zamanıdır. Alkol akıllı işaretlere maruz kalma nüks <sup>3,4</sup> kolaylaştırmak alkol arayan davranışları teşvik edebilir alkol aşerme gibi şartlanmış tepkiler, ortaya çıkarabilir. </p><p class="jove_content"> Alkol tüketimine neden davranış basmakalıp dizileri uyaranların bazı türleri rutin alkol alımının farmakolojik etkileri hemen önce yaşanan neden olabilir. Örneğin, görme, koku ve alkol tadı güvenilir sarhoşluk öncesinde alkol duyusal özellikleri vardır. &quot;Farklı &#39;veya&#39; Proksima&#39;ya olarak adlandırılır Bu ipuçları, ek olarakl &#39;ipuçları, ilaçlar düzenli ayrıca özlem <sup>5,6</sup> provoke edebilir kullanıldığı çevresel bağlamlarda. Ilaçlar, daha önce bu nedenle <sup>7</sup> nüks için kritik bir tetikleyicisi olabilir ikinci edildiği fiziksel konuma maruz kalma. </p><p class="jove_content"> Hayvan modelleri ilaç arayışı davranışı <sup>8-13</sup> ilaca bağlı bağlamlarda etkisini aracılık nöral mekanizmalarını incelemek için geliştirilmiştir. Burada açıklanan prosedür alkol tüketimi ile ilişkili bağlamları ayrı, alkol akıllı Pavlovyan ipucu tarafından ortaya çıkarmasa alkol arama davranışını modüle nasıl soruşturma için izin verir. </p><p class="jove_content"> Pavlovyan ayrımcılık eğitim sıçan davranışsal iki işitsel koşullanmış uyaran, alkol ile eşleştirilmiş bir CS + ve olmayan bir CS- ayırt eğitilmiş belirli bir çevresel bağlamda, yapılır. Extinction oturumları sonra CS yanıt farklı bir bağlamda, yapılmaktadırAlkol sonucu tevkif ediliyor gibi + azalır. Daha sonra, alkol ilişkili Pavlovyan eğitim bağlamında için reexposure CS- yanıt olarak hiçbir değişiklik CS + tarafından ortaya çıkarılan alkol arama davranışı seçici bir artış, tetikler. Biz sürekli <sup>9,14-16</sup> çoğaltılmadan Bu sonuç, ilaç bağlamlar ilaç dağıtım <sup>10,13</sup> ile ilişkili edimsel tepkilerin yenilenmesini uyardıkları bulunmuştur hangi vesile klima prosedürler bulgularını uzanır. </p>

<table><tbody><tr><td>Heavy-duty utility cart</td><td>Rubbermaid</td><td>#4520-88</td><td>Used to transport rats in their home cage from the colony room to the behavior room or other facilities</td></tr><tr><td>Rats, Long-Evans</td><td>Harlan</td><td></td><td>Rats weighed 220-240 g on arrival</td></tr><tr><td>Ohaus scale</td><td>Fisher</td><td>#S402421</td><td>For weighing rats; tare the bottom of a plastic container first, then put the rat in it to weigh it</td></tr><tr><td>Beta-chips, aspen</td><td>Harlan</td><td>#7090A</td><td>Bedding for home cage</td></tr><tr><td>Nylabone</td><td>Bio-Serv</td><td>#K3580</td><td>Enrichment provided in the home cage</td></tr><tr><td>Autoclavable rodent chow</td><td>Agribrands, Charles River</td><td>#5075</td><td>For feeding rats</td></tr><tr><td>Wire bar cage lid</td><td>Ancare</td><td>#R20SS2B</td><td>Custom made with two slots for&amp;nbsp; bottles</td></tr><tr><td>Cage bottom</td><td>Ancare</td><td>#R20PC</td><td>To house rats</td></tr><tr><td>Stoppers</td><td>Ancare</td><td>#8.5</td><td>Rubber stoppers to occlude opening in water bottles &amp;amp; graduated cylinders; goes with ball point sipper tubes&amp;nbsp;</td></tr><tr><td>Ball point tubes, 1.5&quot; length</td><td>Ancare</td><td>#TD-99</td><td>Inserted in stoppers, enables rats to drink from water bottles and graduated cylinders</td></tr><tr><td>Water bottles</td><td>Ancare</td><td>#FSPC8HT</td><td>473 ml (16 oz) capacity, needs to be occluded with stopper</td></tr><tr><td>Graduated cylinders, 100 ml</td><td>Fisher</td><td>#0300741</td><td>To contain ethanol during alcohol exposure in the home cage; spouted end needs to be cut off to enable occlusion with stoppers</td></tr><tr><td>Mettler scale</td><td>Mettler Toledo</td><td>#MS6001S</td><td>For weighing water bottles and ethanol cylinders</td></tr><tr><td>Polyethylene tubing, 1/32&quot; inner diameter,&amp;nbsp; 1/32&quot; wall thickness, 3/32&quot; outside diameter</td><td>Fisher</td><td>#14-169-1A</td><td>To connect 20 ml ethanol syringe to fluid port</td></tr><tr><td>Needle, 18 g, 1.5&quot; length</td><td>Fisher</td><td>#B305199</td><td>To connect polyethylene tubing to ethanol syringes; needs to be filed</td></tr><tr><td>Syringes, 20 ml, Luer-Lok non-sterile</td><td>Fisher</td><td>#1482316J</td><td>To contain ethanol on the fluid pumps; needs to be connected to the polyethylene tubing by a 18 G 1 1/2 needle</td></tr><tr><td>Syringes, 60 ml, Luer-Lok non-sterile</td><td>Fisher</td><td>#14-820-11</td><td>To flush polyethylene tubing after PDT sessions</td></tr><tr><td>Single speed syringe pump, 3.33 rpm</td><td>Med Associates Inc.</td><td>#ENV-018MD</td><td>To hold 20 ml ethanol syringes and deliver ethanol</td></tr><tr><td>Fluid port</td><td>Med Associates Inc.</td><td>#ENV-254-CB</td><td>To enable ethanol delivery during PDT sessions; connected to ethanol syringes with polyethylene tubing</td></tr><tr><td>Port entry infrared detector</td><td>Med Associates Inc.</td><td>#ENV-215M</td><td>Fixed on both sides of&amp;nbsp; fluid port; need 2 per fluid port</td></tr><tr><td>Houselight, 28 V, 100 mA</td><td>Med Associates Inc.</td><td>#ENV-135M</td><td>Provides general lighting in conditioning chamber</td></tr><tr><td>Clicker module</td><td>Med Associates Inc.</td><td>#ENV-225SM</td><td>Auditory stimulus for conditioning chamber</td></tr><tr><td>White noise generator with speaker</td><td>Med Associates Inc.</td><td>#PHM-100</td><td>Auditory stimulus for conditioning chamber</td></tr><tr><td>Bar floor</td><td>Med Associates Inc.</td><td>#ENV-009A-GF</td><td>To go with modular test chamber</td></tr><tr><td>Bench coat, absorbent</td><td>VWR</td><td>#89126-790</td><td>Absorbent paper to put in metal tray, needs to be cut to fit the metal tray</td></tr><tr><td>Polycarbonate sheet, 1/8&quot; thick, 12-5/8&quot; x 10&quot;</td><td>Johnston Plastics</td><td>#30102515</td><td>To make smooth transparent floor insert used for context 1. Needs to be cut in 11.5&quot; x 12.25&quot; pieces</td></tr><tr><td>Aluminium sheet perforated, 0.063&quot; thick, 48&quot; x 96&quot;, 0.250&quot; holes x 0.375&quot; centers</td><td>Anica Steel</td><td></td><td>To make perforated floor insert used for context 2. Needs to be cut in 11.5&quot; x 12.25&quot; pieces</td></tr><tr><td>Black cardboard, 0.053&quot; thick, 28&quot; x 44&quot;</td><td>Omer DeSerres</td><td>#P1909</td><td>To construct panels covering the ceiling, door and back wall of the conditioning chamber in context 1. Needs to be cut to size. Each chamber needs three panels measuring approximately 11.5&quot; x 13.25&quot;. The panels can be joined by the narrower side using duct tape.</td></tr><tr><td>All-purpose strength duct tape, 1.88&quot; x 45 yd.</td><td>Duck Tape</td><td></td><td>Adhesive material to connect the black cardboard panels used to cover the back wall, ceiling and door in context 1.</td></tr><tr><td>Modular test chamber</td><td>Med Associates Inc.</td><td>#ENV-009A</td><td>Conditioning chamber</td></tr><tr><td>Sound attenuating cubicles</td><td>Med Associates Inc.</td><td>#ENV-200R3AM</td><td>Comes with installed 28 V DC fan (#ENV-025F)</td></tr><tr><td>Petri dish</td><td>Fisher</td><td>#08748B</td><td>Bottom only, to contain the sprayed solution that provides the odor stimulus; needs to be centered in the metal tray in conditioning chambers</td></tr><tr><td>PCI interface package</td><td>Med Associates Inc.</td><td>#DIG-700P2-R2</td><td>Connects tabletop interface cabinet to computer; includes 1 interface card, 1 Decode card, 1 ribbon cable and 1 28 V DC power cable</td></tr><tr><td>Large tabletop cabinet and power supply</td><td>Med Associates Inc.</td><td>#SG-6510D</td><td>Used to contain the 12 cards included in the SmartCrtrl 8 Input, 16 Output package</td></tr><tr><td>SmartCtrl 8 Input, 16 Output package</td><td>Med Associates Inc.</td><td>#DIG-716P2</td><td>Used to connect and control the devices in the conditioning chamber. The package includes all the cables, the interface module and the connection panel.</td></tr><tr><td>Med PC IV software</td><td>Med Associates Inc.</td><td>#SOF-735</td><td>Software to run programs. Needs to be installed on the computer.</td></tr><tr><td>Monitor LG, 19&quot; LCD</td><td>Concordia computer store</td><td>#W1942TQ-BF</td><td>Computer monitor; to go with computer running Med PC IV</td></tr><tr><td>HP Z200 tower workstation</td><td>Concordia computer store</td><td>#BZ788US#ABA</td><td>Computer on which Med PC IV is run</td></tr><tr><td>Benzaldehyde, &amp;ge;99%</td><td>Les produits chimiques OMEGA Chemical Company Inc.</td><td>#B37-50</td><td>Dilute in tap water for almond context odor</td></tr><tr><td>Lemon oil, cold pressed, California</td><td>Sigma Aldrich</td><td>#W262528-1KG-K</td><td>Dilute in tap water for lemon context odor</td></tr><tr><td>Ethyl alcohol, 95%</td><td>Commercial Alcohols</td><td></td><td>Dilute in tap water to desired concentration</td></tr></tbody></table>

a procedure to observe context-induced renewal of pavlovian-conditioned alcohol-seeking behavior in rats

<p class="jove_content"> Çevre bağlamlarda hangi ilaç kötüye özlem, kanaatkâr uyuşturucu kullanıcılarının uyuşturucu arama davranışını ve hızlı nüks kolaylaştırabilir öznel bir Pavlovyan klimalı tepkisini tetikleyebilir tüketilir. Biz sıçanlarda alkol-arama davranışının bağlam etkisini aracılık davranışsal ve nöral süreçleri incelemek için bir prosedür geliştirmiştir. Tat aklimasyonundan ve evde kafes içinde% 15 etanol farmakolojik etkileri takiben, erkek Long-Evans sıçan klima odalarına Pavlovyan ayrımcılık eğitimi (PDT) alırsınız. Her günlük (Pazartesi-Cuma) PDT oturumunda, 16 denemeler iki farklı 10 sn işitsel koşullanmış uyaran her oluşur. Bir uyarıcı sırasında, CS +,% 15 etanol içinde, 0.2 ml, oral tüketim için bir sıvı giriş içerisine verilir. İkinci uyaran, CS, etanol ile eşleştirilmiş değil. Seans boyunca, CS- sırasında girişleri ise CS + artışı sırasında sıvı portuna girişleri bir Predi belirten, daha düşük bir seviyede stabilizeCS + ve etanol arasında ctive ilişki elde edilir. PDT sırasında her odası, görsel koku ve dokunma bağlamsal uyaranlara belirli bir yapılandırma ile donatılmıştır. PDT sonra, söndürme eğitim toplam içeriğe uyarıcıların farklı bir konfigürasyona sahiptir, aynı hücre içerisinde gerçekleştirilir. CS + ve CS önce olduğu gibi sunulmaktadır, ancak etanol CS + sırasında liman girişlerinde kademeli bir düşüş neden olan tevkif edilir. Test, sıçanlar, PDT bağlamında bir yere yerleştirilir ve daha önce olduğu gibi CS + ve CS- ile sunulmaktadır, etanol yoktur. Bu manipülasyon CS- sırasında yanıt hiçbir değişiklik ile akıllı CS + alkol sırasında yapılan liman girişlerinin sayısında sağlam ve seçici bir artış, tetikler. Bağlam kaynaklı yenileme olarak adlandırılan bu etki, Pavlovyan alkol uyaranlara yanıt olarak alkol arayan davranışları teşvik etmek alkol tüketimi ile ilişkili bağlamlarda güçlü kapasitesini göstermektedir. </p>

<p class="jove_content"> Evde kafes içinde Aralıklı etanol erişim: - 12 seans <strong>(Şekil 1)</strong> Etanol tüketimi (g / kg) ve evde kafes içinde aralıklı etanol erişim oturumları boyunca etanol tercihi artış, genellikle 8 içinde istikrarlı seviyelere ulaştı. <strong>Şekil 1&#39;de</strong> gösterildiği veri setinde, kararlı etanol tüketimi ev kafes etanol erişim son iki seans arasında ortalama 1.33 arasında değişmektedir - bireysel sıçanlar için 6.44 g / kg. Ug / kg tüketimi kızağa sonra deney ev kafesinde etanol tüketimini faz durdurulabilir ve sıçanlar seans bir dizi içme bu kararlı bir düzeyde tutulur. </p><p class="jove_content"> Bu aşamada verileri analiz etmek, etanol tüketimi (g / kg) ve etanol tercihi için oturumun denek içi faktör karşısında varyans (ANOVA) ayrı tekrarlanan ölçümler analizi yapmak. </p><p class="jove_content"> Bağlam-kaynaklı yenileme prosedürünün şematik: Her aşamasıdeneysel işlem (PDT, sönme, yenileme testi) <strong>Şekil 2&#39;de</strong> gösterilmiştir. daha detaylı bilgi için rakam başlığa bakın. </p><p class="jove_content"> Tepki önlemleri ve veri analizi: Aşağıda açıklanan tüm davranış aşamalarında, CS + ve CS- sırasında yapılan liman giriş tepkiler taban port girişi yanıtları-CS öncesi referans normalize edilir. Normalize CS tedbirleri oluşturmak için, ön-CS bazal aralığında yapılan liman girişlerinin sayısını CS + ve CS- sunumlarına sırasında yapılan liman girişlerinin sayısından (CS başlangıcından hemen önce 10 sn) çıkarma. Davranış göstergeleri baz seviyenin üzerinde yükseltilmiş CS sunumlar, spesifik olarak ortaya olarak normalize CS + ve normalize CS tedbirler hizmet vermektedir. </p><p class="jove_content"> Ayrı tekrarlanan ölçümler ANOVA PDT ve sönme aşamaları için oturumu ve CS tipi (CS- vs CS +) tekrarlanan denek içi faktörler ile yürütün. Fazında karşılaştırmalar (PDT, sönme, yenilemekark testi), kullanımı, veri PDT ve nesli son iki seans ve tekrarlanan önlemler ANOVA yenilenme test verilerinin tek oturumda genelinde ortalama. Çoklu karşılaştırmalar için düzeltilmiştir bağımsız veya bağımlı örnekler için anlamlı temel etkileri ve etkileşimleri, kullanım <em>post hoc</em> t-testi takip etmek. Anlamlılık için Kriter α = 0.05 olarak belirlenmiştir. </p><p class="jove_content"> PDT: seans FDT genelinde CS + artışa Liman giriş yanıtları, CS- liman giriş tepkiler genel olarak, düşük ve istikrarlı kalır ise. PDT eğitim erken seanslarda biraz artabilir CS- bu port girişi yanıtları Not; Bununla birlikte, CS- yanıt olarak yapılan bağlantı girişleri CS + &#39;ya karşılık olarak yapılan daha çok daha düşük bir düzeyde kararlı hale getirir. Başarılı ayrımcılık CS sırasında liman girişlerinde istatistiksel olarak anlamlı yükselme gösterdiği + CS- <strong>(Şekil 3)</strong> ile karşılaştırılır. Bu sonuç Pavlovyan-klimalı alkol arama davranışı olması olduğunu gösterirtr CS CS + kurulmuş, ancak. </p><p class="jove_content"> Extinction: CS + Port giriş tepkiler giderek söndürme oturumlar boyunca düşüş. CS- Port giriş tepkiler söndürme oturumlar boyunca düşük ve istikrarlı kalır. İdeal olarak, CS + ve CS- port girişleri arasında istatistiksel olarak anlamlı fark olmaması kanıtladığı gibi, nesli eğitim sonunda kaldırılmıştır yanıt ayrımcılık. Ancak, hatta nesli eğitim sonunda kalır yanıt ayrımcılığa bazı derecesi için nadir değildir. Bu durumda, söndürme eğitimi, tükenme başında CS + port girişi yanıtların istatistiksel olarak daha düşük olduğu gibi FDT sonunda sonunda CS + port giriş tepkilerini doğrulamak için önemlidir <strong>(Şekil 3)</strong> . Bu sonuç paterni-Pavlovyan klimalı alkol arama davranışı önemli ölçüde sönmüş olduğunu gösterir. </p><p class="jove_content"> Bağlam kaynaklı yenileme testi: Limansöndürme eğitimi sonunda gözlenen CS + port girişleri göre bağlam kaynaklı yenileme testinde CS + artışı, için giriş yanıtları. CS- port girişleri değişmeden kalır gibi bu artış, CS + seçicidir. Buna ek olarak, bundan dolayı CS + &#39;ya bağlantı girişleri bağlam kaynaklı yenileme test CS- port girişlerinin <strong>(Şekil 4)</strong> ile karşılaştırıldığında istatistiksel olarak yükselir. CS + port nesli ve test arasındaki girdileri yanı sıra CS + ve test içindeki CS liman girişlerinin karşılaştırmalar karşılaştırmalar istatistiksel onay, testte alkol ilişkili bağlamı tarafından uyarılan Pavlovyan klimalı alkol arama davranışı seçici yenilenmesini gösterir. </p><p class="jove_content" fo:keep-together.within-page="always"><img alt="Şekil 1" fo:content-width="4in" src="/files/ftp_upload/51898/51898fig1highres.jpg" width="400" /><br /> <strong>Etanol tüketimi ve evde kafes içinde aralıklı etanol erişim tarafından uyarılan tercih 1. Eskalasyon Şekil.</strong> &amp; Ortalama# 177; SEM <strong>(A)</strong> etanol tüketimi (g / kg) ve evde kafes içinde aralıklı etanol erişim 12 seans boyunca <strong>(B)</strong> etanol tercihi. Her iki tedbir genellikle oturumlar boyunca artırmak ve daha sonra stabilize. Bireysel fareler için 6.44 g / kg - Durağan etanol tüketimi 1,33 arasında değişiyordu ev kafes etanol erişim son iki seans arasında ortalama. Bu veriler,% 15 (h / h) etanol içme Erkek Long-Evans sıçanları kullanılarak elde edilmiştir. </p><p class="jove_content" fo:keep-together.within-page="always"><img alt="Şekil 2" fo:content-width="4in" src="/files/ftp_upload/51898/51898fig2highres.jpg" width="400" /><br /> <strong>. Şekil 2. Deneysel işlemin şematik bir</strong> prosedür üç aşamadan oluşmaktadır: Pavlovyan ayrımcılık eğitimi (PDT), tükenme ve bağlam-kaynaklı yenileme testi. Her PDT oturumu sırasında, sıçanlar etanol teslimi ve 16 denemeler bir işaret, bir işitsel klimalı uyaran (CS +) 16 denemeler almaketanol doğum ile ilişkili olmayan bir ikinci işitsel uyaran (CS). Seans FDT görsel, koku alma belirli yapılandırması ve dokunsal uyaranlara oluşan, Bağlam A&#39;da gerçekleşecek. , Görsel koku ve dokunsal uyaranlara farklı bir dizi oluşur Bağlam B yapılmaktadır söndürme oturumları, sırasında, CS + ve CS sunulmaktadır ancak etanol tevkif edilir. Bağlam-kaynaklı yenileme testi için, sıçanlar Bağlam A iade edilir, ve CS + ve CS etanol olmadan sunulmaktadır. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/51898/51898fig2highres.jpg" target="_blank">, bu rakamın büyük bir versiyonunu görmek için lütfen buraya tıklayınız.</a> </p><p class="jove_content" fo:keep-together.within-page="always"><img alt="Şekil 3," fo:content-width="4in" src="/files/ftp_upload/51898/51898fig3highres.jpg" width="400" /><br /> <strong>Şekil 3. Toplama ve ayrımcılığa Pavlovyan klimalı etanol için yanıt.</strong> Ortalama ± SEM normalize liman girişleri <strong>m söndürme</strong>Bağlam A ve sönme (oturumları 19-26) - PDT arasında CS + ve CS- boyunca (18 seans 1) ge Bağlam B&#39;de Bu veriler,% 10 eğitimli Erkek Long-Evans sıçanları kullanılarak elde edildi (h / h) PDT sırasında CS + ile birlikte sunuldu koşulsuz uyarıcı (ABD) gibi etanol. * P &lt;0.05, CS- karşı CS +. Şekil başlangıçta Chaudhri, Sahuque &amp; JANAK (2008) yayınladı. Elsevier izni ile kullanılabilir. </p><p class="jove_content" fo:keep-together.within-page="always"><img alt="Şekil 4" fo:content-width="5in" src="/files/ftp_upload/51898/51898fig4highres.jpg" width="500" /><br /> <strong>Şekil 4. Bağlam kaynaklı</strong> Bağlam A. Data <strong>Pavlovyan klimalı etanol için yanıt.</strong> Ortalama Bağlam A PDT oturumlarında CS + ve CS- sırasında yapılan ± SEM normalize liman girişleri, Bağlam B söndürme oturumları ve yenileme <strong>testi yenilenmesidir</strong> PDT ve nesli için son iki seans üzerinden ortalama; yenileme testi tek bir oturumu. BuVeri PDT sırasında CS + ile birlikte sunuldu koşulsuz uyarıcı (ABD) ve% 10 (h / h) etanol ile eğitim Erkek Long-Evans fareleri kullanılarak elde edilmiştir. * P &lt;0.05; ** P &lt;0.001, CS- karşı CS +. #p &lt;0.05, CS + nesli karşı CS + PDT. ^ P &lt;0.05, CS + testi karşı CS + sönme. Şekil başlangıçta Chaudhri, Sahuque &amp; JANAK (2008) yayınladı. Elsevier izni ile kullanılabilir. </p>

Watch this Scientific Journal Video about A Procedure to Observe Context-induced Renewal of Pavlovian-conditioned Alcohol-seeking Behavior in Rats at JoVE.com

A Procedure to Observe Context-induced Renewal of Pavlovian-conditioned Alcohol-seeking Behavior in Rats

<p class="jove_content"> Bir prosedür, sıçanlarda alkol arama davranışının yenilenmesi açıklanan tetiklemek için, bir alkol ilişkili çevre koşullarından kapasitesini incelemek. </p>

Usulü Sıçanlar Pavlovyan klimalı Alkol arayan Davranış Bağlam kaynaklı Yenileme İnceleyecek

Environmental contexts in which drugs of abuse are consumed can trigger craving, a subjective Pavlovian-conditioned response that can facilitate ...

a-procedure-to-observe-context-induced-renewal-pavlovian-conditioned

Nanyang Technological University

Research

JoVE Journal

Behavior

12.7K Görüntüleme.  Concordia University.  Bir prosedür, sıçanlarda alkol arama davranışının yenilenmesi açıklanan tetiklemek için, bir alkol ilişkili çevre koşullarından kapasitesini incelemek. 

Video: A Procedure to Observe Context-induced Renewal of Pavlovian-conditioned Alcohol-seeking Behavior in Rats

Esterification

<p>Source: Lara Al Hariri at the University of Massachusetts Amherst, MA, USA</p>
<ol class="note-items">
	<li data-note-item="1" data-parent-collapse="">Preparation of the Laboratory<button class="expand">Expand</button>
	<p><em>Here, we show the laboratory preparation for 10 students working in pairs, with some excess. Please adjust quantities as needed.</em></p>
	<ul class="lab-items">
		<li data-sub-note-item="1-2">
		<div class="lab-step">First, put on a lab coat, safety glasses, and nitrile gloves.<strong> Note:</strong> Some of the reagents are volatile or have unpleasant odors, so you will handle them in a fume hood.</div>
		</li>
		<li data-sub-note-item="1-3">
		<div class="lab-step">Ensure that you have glass and organic waste containers and that each sink has paper towels.</div>
		</li>
		<li data-sub-note-item="1-4">
		<div class="lab-step">Follow the table to designate codes for the carboxylic acids and alcohols used in this lab. The carboxylic acids are coded A through C, and the alcohols are coded D through I. The students will use a 3:1 molar ratio of alcohol to carboxylic acid in the reaction.
		<table align="center" height="224" style="border-collapse: collapse; font-size: 17px; line-height: 24px;">
			<tbody>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;"><strong>Code</strong></td>
					<td style="border: 1px solid; padding: 0px; text-align: center;"><strong>Compound</strong></td>
					<td style="border: 1px solid; padding: 0px; text-align: center;"><strong>MW<br />
					(g/mol) </strong></td>
					<td style="border: 1px solid; padding: 0px; text-align: center;"><strong>Density at RT (g/cm<sup>3</sup>)</strong></td>
					<td style="border: 1px solid; padding: 0px; text-align: center;"><strong>Moles per vial</strong></td>
					<td style="border: 1px solid; padding: 0px; text-align: center;"><strong>Grams per vial</strong></td>
					<td style="border: 1px solid; padding: 0px; text-align: center;"><strong>cm<sup>3</sup> per vial </strong></td>
					<td style="border: 1px solid; padding: 0px; text-align: center;"><strong>Number of vials</strong></td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">A</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Acetic acid</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">60.05</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">1.049</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.07</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">4.2035</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">4.0</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">3</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">B</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Butyric acid</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">88.11</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.953</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.07</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">6.1677</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">6.5</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">3</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">C</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Anthranilic acid</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">137.14</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">-</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.07</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">9.5998</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">-</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">1</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">D</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">1-Propanol</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">60.10</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.803</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.21</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">12.6210</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">15.7</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">1</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">E</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Isoamyl alcohol</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">88.15</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.810</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.21</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">18.512</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">22.8</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">1</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">F</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">1-Butanol</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">74.12</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.810</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.21</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">15.565</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">19.2</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">1</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">G</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Ethanol</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">46.07</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.789</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.21</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">9.6747</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">12.3</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">1</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">H</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Methanol</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">32.04</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.791</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.21</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">6.7284</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">8.5</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">2</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">I</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">1-Octanol</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">130.23</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.830</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">0.21</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">27.348</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">32.9</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">1</td>
				</tr>
			</tbody>
		</table>
		</div>
		</li>
		<li data-sub-note-item="1-5">
		<div class="lab-step">Prepare the three carboxylic acids: acetic acid, butyric acid, and anthranilic acid. Each group will need 0.07 moles of their assigned carboxylic acid in a vial.</div>
		</li>
		<li data-sub-note-item="1-6">
		<div class="lab-step">Tare a 10-mL glass vial on an analytical balance in a fume hood. Use a Pasteur pipette to measure 4.2035 g of acetic acid, which will be about 4 mL. Cap the vial and label it &#8216;A&#8217;. Prepare two more labeled vials of acetic acid in the same way.</div>
		</li>
		<li data-sub-note-item="1-7">
		<div class="lab-step">Weigh 6.1677 g of butyric acid, which will be about 6.5 mL, in a tared 10-mL vial. Cap the vial and label it &#8216;B&#8217;. Prepare two more vials of butyric acid in the same way.</div>
		</li>
		<li data-sub-note-item="1-8">
		<div class="lab-step">Use a small spatula to weigh 9.5998 g of solid anthranilic acid in a tared 10-mL vial. Cap the vial and label it &#8216;C&#8217;. You should now have a total of seven vials of carboxylic acid.</div>
		</li>
		<li data-sub-note-item="1-9">
		<div class="lab-step">Prepare the 7 alcohols. Each group will need 0.21 moles of their assigned alcohol in a vial. Use the table as a guide to prepare and label one vial of each alcohol. Prepare and label two vials of methanol.</div>
		</li>
		<li data-sub-note-item="1-10">
		<div class="lab-step">You should now have a total of seven vials of alcohol. Keep the reagent vials in the instructor&#39;s hood for now and put away the stock bottles of the carboxylic acids and alcohols.</div>
		</li>
		<li data-sub-note-item="1-11">
		<div class="lab-step">Assign each student group one of these seven combinations of reagents.
		<table align="center" height="224" style="border-collapse: collapse; font-size: 17px; line-height: 24px;">
			<tbody>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;"><strong>Ester code</strong></td>
					<td style="border: 1px solid; padding: 0px; text-align: center;"><strong>Carboxylic acid </strong></td>
					<td style="border: 1px solid; padding: 0px; text-align: center;"><strong>Alcohol</strong></td>
					<td style="border: 1px solid; padding: 0px; text-align: center;"><strong>Ester product</strong></td>
					<td style="border: 1px solid; padding: 0px; text-align: center;"><strong>Scent</strong></td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">AD</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Acetic acid</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">1-Propanol</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Propyl acetate</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Pear</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">AE</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Acetic acid</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Isoamyl alcohol</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Isoamyl acetate</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Banana</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">AI</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Acetic acid</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">1-Octanol</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Octyl acetate</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Orange</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">BF</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Butyric acid</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">1-Butanol</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Butyl butyrate</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Pineapple</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">BG</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Butyric acid</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Ethanol</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Ethyl butyrate</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Strawberry</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">BH</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Butyric acid</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Methanol</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Methyl butyrate</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Apple</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px; text-align: center;">CH</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Anthranilic acid</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Methanol</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Methyl anthranilate</td>
					<td style="border: 1px solid; padding: 0px; text-align: center;">Grape</td>
				</tr>
			</tbody>
		</table>
		</div>
		</li>
		<li data-sub-note-item="1-12">
		<div class="lab-step">Prepare or obtain seven vials of the fruit scents and label them with the fruit names as references.</div>
		</li>
		<li data-sub-note-item="1-13">
		<div class="lab-step">Set out the following glassware and equipment at each student lab station (we suggest that students work in pairs):</div>
		</li>
		<li data-sub-note-item="1-14">
		<div class="lab-step">Put bottles of saturated sodium bicarbonate and 3 M sulfuric acid in a dedicated fume hood, along with a roll of plastic paraffin film and scissors.</div>
		</li>
		<li data-sub-note-item="1-15">
		<div class="lab-step">Set out filter paper and Pasteur pipettes in a central area so that every student group can easily access them.
		<table align="center" height="224" style="border-collapse: collapse; font-size: 17px; line-height: 24px;">
			<tbody>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;Lab stand</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;2&#160;&#160;&#160;&#160;3-prong clamps</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;Stir plate</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;Lab jack</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;Heating mantle</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;Temperature controller</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;2&#160;&#160;&#160;&#160;Pieces of tubing (for condenser)</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;Joint clip</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;Tube of vacuum grease</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;Box of laboratory wipes</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;10-mL graduated cylinder</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;600-mL beaker</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;50-mL round-bottom flask and flask stand</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;Standard condenser</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;Small stir bar</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;Glass rod</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;1&#160;&#160;&#160;&#160;Package of pH paper</td>
				</tr>
				<tr>
					<td style="border: 1px solid; padding: 0px;">&#160;2&#160;&#160;&#160;&#160;Pasteur pipette bulbs</td>
				</tr>
			</tbody>
		</table>
		</div>
		</li>
		<li data-sub-note-item="1-16">
		<div class="lab-step">Just before the lab, fill a large insulated cooler with crushed ice. Place the cooler and an ice scoop in a central area in the lab.</div>
		</li>
		<li data-sub-note-item="1-17">
		<div class="lab-step">When the students arrive, show them how to safely waft vapors before giving them their assigned reagents.</div>
		</li>
	</ul>
	</li>
</ol>

Esterification: Synthesis of Ester by Fischer Esterification - Prep

Esterleşme

Source: Lara Al Hariri at the University of Massachusetts Amherst, MA, USA

	Preparation of the LaboratoryExpand
	Here, we show the laboratory preparation ...

Education

JoVE Lab Manual

Kimya

Lab Manual Sub Articles

Identifying Alcohols

<p>Source: Lara Al Hariri and Ahmed Basabrain at the University of Massachusetts Amherst, MA, USA</p>
<ol class="note-items">
	<li data-note-item="1" data-parent-collapse="">Ferric Chloride Test for Phenols<button class="expand">Expand</button>
	<p>In this lab, you will identify an unknown alcohol using the ferric chloride test, the Jones test, and the Lucas test. You&#39;ll test known alcohols alongside the unknown alcohol as examples of positive and negative results for each test.</p>
	<p>The four known alcohols are 1-butanol, a primary alcohol, 2-butanol, a secondary alcohol, 2-methyl-2-propanol, a tertiary alcohol, and phenol. The four possible unknown alcohols are 1-propanol, 2-propanol, 2-methyl-2-butanol, and para-chlorophenol.</p>
	<p>You&#39;ll start with the ferric chloride test for the presence of phenols. Iron(III) chloride, or ferric chloride, forms a brown complex when it&#39;s dissolved in water. If you add a phenol to this solution, a purple iron(III)-phenol complex will form instead. This effect is not observed with non-aromatic or aliphatic alcohols.</p>
	<ul class="lab-items">
		<li data-sub-note-item="1-4">
		<div class="lab-step">Put on a lab coat, safety glasses, and gloves before you begin. <strong>Note:</strong> The alcohols that you will test are toxic and flammable, and the reagents that you will use are toxic and corrosive, so you will perform this lab in a fume hood.</div>
		</li>
		<li data-sub-note-item="1-5">
		<div class="lab-step">Now, get your assigned unknown alcohol from your instructor and bring it to your fume hood. Label a 250-mL beaker &#8216;aqueous metal waste&#8217;.</div>
		</li>
		<li data-sub-note-item="1-6">
		<div class="lab-step">Next, put five small test tubes in a rack and label them &#8216;1-butanol&#8217;, &#8216;2-butanol&#8217;, &#8216;2-methyl-2-propanol&#8217;, &#8216;phenol&#8217;, and &#8216;unknown&#8217;. Bring the rack to the analytical balance to obtain phenol.</div>
		</li>
		<li data-sub-note-item="1-7">
		<div class="lab-step">If your unknown is a solid, bring it with you. Weigh about 0.2 g of phenol and pour it into the corresponding tube. Do the same for your unknown if it is a solid and then return to your hood.</div>
		</li>
		<li data-sub-note-item="1-8">
		<div class="lab-step">Now label three small vials &#8216;1-butanol&#8217;, &#8216;2-butanol&#8217;, and &#8216;2-methyl-2-propanol&#8217;.</div>
		</li>
		<li data-sub-note-item="1-9">
		<div class="lab-step">Bring the vials to the solvent hood and use clean Pasteur pipettes to fill each vial with about 1 mL of the matching alcohol.<strong> Note: </strong>Do not reuse pipettes.</div>
		</li>
		<li data-sub-note-item="1-10">
		<div class="lab-step">Next, obtain at least four Pasteur pipettes and a 250-mL beaker. Get more pipettes whenever you need them, and don&#39;t put used pipettes back in the beaker.</div>
		</li>
		<li data-sub-note-item="1-11">
		<div class="lab-step">In your fume hood, pipette 3 &#8211; 4 drops of 1-butanol, 2-butanol, and 2-methyl-2-propanol into the corresponding tubes.</div>
		</li>
		<li data-sub-note-item="1-12">
		<div class="lab-step">To the phenol tube, add several drops of deionized water and shake to mix. This will provide better visual results for the ferric test.</div>
		</li>
		<li data-sub-note-item="1-13">
		<div class="lab-step">If your unknown alcohol is a liquid, use a clean pipette to place 3 &#8211; 4 drops of it in the unknown test tube.</div>
		</li>
		<li data-sub-note-item="1-14">
		<div class="lab-step">Now, obtain the bottle of iron(III) chloride solution and add 2 &#8211; 3 drops to each test tube.</div>
		</li>
		<li data-sub-note-item="1-15">
		<div class="lab-step">Stir each mixture well with a glass rod. Use deionized water to rinse off residual alcohol before mixing the contents of the next tube. Make sure that the phenol dissolves completely along with the unknown if it is a solid.</div>
		</li>
		<li data-sub-note-item="1-16">
		<div class="lab-step">Wait 5 min before comparing your unknown to the known solutions. <strong>Note:</strong> If your unknown solution is purple, like the phenol solution, then your unknown is a phenol derivative. If it looks like the other three tubes, it is not a phenol derivative. Record the results of the test in your lab notebook.
		<h4><strong>Table 1: Identifying Unknown Alcohol</strong></h4>
		<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
			<tbody>
				<tr>
					<td style="text-align: center;"><strong>Alcohol</strong></td>
					<td style="text-align: center;"><strong>Ferric Chloride Test</strong></td>
					<td style="text-align: center;"><strong>Jones Test</strong></td>
					<td style="text-align: center;"><strong>Lucas Test</strong></td>
				</tr>
				<tr>
					<td>1-butanol</td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
				</tr>
				<tr>
					<td>2-butanol</td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
				</tr>
				<tr>
					<td>2-methyl-2-propanol</td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
				</tr>
				<tr>
					<td>Phenol</td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
				</tr>
				<tr>
					<td>Unknown</td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
				</tr>
			</tbody>
		</table>
		<a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/71/Table_1._Identifying_unknown_alcohol.xlsx" target="_blank">Click Here to download Table 1</a></div>
		</li>
		<li data-sub-note-item="1-17">
		<div class="lab-step">The next tests don&#39;t work with phenols, so you&#39;ll only test aliphatic alcohols for the rest of the lab. If your unknown is a phenol derivative, skip the instructions for the unknown and test only the three known aliphatic alcohols.</div>
		</li>
	</ul>
	</li>
	<li data-note-item="2" data-parent-collapse="">The Jones Test for Aliphatic Primary and Secondary Alcohols<button class="expand">Expand</button>
	<p>In this section, you&#39;ll perform the Jones test for primary and secondary alcohols. Jones&#39; reagent is made with chromium trioxide and sulfuric acid in water, which forms chromic acid (H<sub>2</sub>CrO<sub>4</sub>)<em> in situ</em>. This powerful reagent oxidizes secondary alcohols to ketones, primary alcohols to aldehydes, which after forming an aldehyde hydrate, are further reduced to carboxylic acids.</p>
	<p>The oxidation state of chromium is the key to this test. Chromium is in the +6 oxidation state in the Jones&#39; reagent. The Cr(VI) complexes in the reagent give it its bright reddish, orange color.</p>
	<p>When Cr(VI) oxidizes an alcohol, chromium is reduced to the +3 oxidation state. First, the alcohol and chromic acid form a chromate ester. Then, a base (H<sub>2</sub>O) cleaves the C-H bond of the alcohol, forming the carbonyl group while reducing Cr(VI) to Cr(IV). Because the carbon of the alcohol undergoes a 2-electron oxidation, and Cr(VI) a 2-electron reduction, this step is a reduction-oxidation step. Cr(IV) participates in further oxidation steps and is eventually reduced to Cr(III). Cr(III) is often present as hexaaquachromium(III) ions&#160;&#8212; [Cr(H<sub>2</sub>O)<sub>6</sub>]<sup>3+</sup> &#8212; and Cr(III) complexes, where H<sub>2</sub>O molecules are replaced by one or more sulphate ions, [Cr(H<sub>2</sub>O)<sub>5</sub>(SO<sub>4</sub>)]<sup>+</sup>. These complexes give Cr(III) the characteristic green color. So, when you mix Jones&#39; reagent with a primary or secondary alcohol in acetone, the orange solution will turn green.</p>
	<p>Jones oxidation of alcohols doesn&#39;t work with tertiary alcohols because the -OH group is already bonded to three carbon atoms and cannot form an extra C-O bond. Thus, you won&#39;t see a color change if you combine Jones&#39; reagent with a tertiary alcohol because chromium isn&#39;t reduced.</p>
	<ul class="lab-items">
		<li data-sub-note-item="2-5">
		<div class="lab-step">Label four clean test tubes &#8216;1-butanol&#8217;, &#8216;2-butanol&#8217;, &#8216;2-methyl-2-propanol&#8217;, and &#8216;unknown&#8217; and place 10 drops of acetone in each. Acetone is the preferred solvent for Jones oxidation.</div>
		</li>
		<li data-sub-note-item="2-6">
		<div class="lab-step">Then, use clean pipettes to add 3 &#8211; 4 drops of the known aliphatic alcohols and your unknown alcohol to the corresponding tubes.</div>
		</li>
		<li data-sub-note-item="2-7">
		<div class="lab-step">Stir each solution well with the glass rod and rinse the rod with water after mixing each one.</div>
		</li>
		<li data-sub-note-item="2-8">
		<div class="lab-step">Now, obtain the bottle of Jones&#39; reagent and carefully add 2 &#8211; 3 drops to each tube. The reagent is strongly acidic and corrosive, so be careful with it and tightly cap the bottle when you&#39;re done. Then, mix each solution well, cleaning the glass rod after each one.</div>
		</li>
		<li data-sub-note-item="2-9">
		<div class="lab-step">Let the solutions react for 10 min, and then compare your unknown to the knowns. <strong>Note:</strong> If the unknown solution turned green, like 1-butanol and 2-butanol, the test is positive for a primary or secondary alcohol. If it stayed orange, like 2-methyl-2-propanol, the test is negative.</div>
		</li>
		<li data-sub-note-item="2-10">
		<div class="lab-step">Record the results in your lab notebook.</div>
		</li>
	</ul>
	</li>
	<li data-note-item="3" data-parent-collapse="">The Lucas Test for Classifying Small Saturated Alcohols<button class="expand">Expand</button>
	<p>The Jones test doesn&#39;t distinguish between primary and secondary alcohols, so you&#39;ll use the Lucas test to identify which is which.</p>
	<p>Lucas&#39; reagent, which is a mixture of zinc chloride and hydrochloric acid, converts secondary and tertiary alcohols to chloroalkanes at room temperature. Chloroalkanes are nearly insoluble in water, so a positive result appears as the mixture separates into a cloudy chloroalkane-containing layer over a clear layer.</p>
	<p>The rate-determining step of the reaction involves converting the alcohol to a carbocation, so the speed of the reaction depends on how stable the carbocation is.</p>
	<p>Tertiary carbocations are very stable, so tertiary alcohols give a positive reaction almost immediately. Secondary carbocations are less stable, so secondary alcohols give a positive result after a few seconds to a few minutes. Primary carbocations are too unstable for this reaction, so primary alcohols give a negative result.</p>
	<ul class="lab-items">
		<li data-sub-note-item="3-5">
		<div class="lab-step">Now, label for clean test tubes as &#8216;1-butanol&#8217;, &#8216;2-butanol&#8217;, &#8216;2-methyl-2-propanol&#8217;, and &#8216;unknown&#8217;.</div>
		</li>
		<li data-sub-note-item="3-6">
		<div class="lab-step">Obtain the bottle of Lucas&#39; reagent and use a graduated cylinder to measure 2 mL of the reagent for each tube.</div>
		</li>
		<li data-sub-note-item="3-7">
		<div class="lab-step">Next, add 2 drops of 2-methyl-2-propanol to the appropriate tube. Immediately, stir the mixture for a few seconds and place it in the rack. The mixture will promptly separate into a clear lower layer and a cloudy upper layer.</div>
		</li>
		<li data-sub-note-item="3-8">
		<div class="lab-step">Thoroughly rinse the glass rod and record the immediate positive result in your lab notebook.</div>
		</li>
		<li data-sub-note-item="3-9">
		<div class="lab-step">Mix the remaining alcohols with Lucas&#39; reagent in the same way, using a fresh pipette for each alcohol and rinsing the glass rod each time. <strong>Note:</strong> Don&#39;t add too much alcohol or jostle the tubes because that can slow down the reaction.</div>
		</li>
		<li data-sub-note-item="3-10">
		<div class="lab-step">Watch carefully after mixing the unknown alcohol with Lucas&#39; reagent to ensure that you can distinguish an immediate positive result from a positive result after a brief delay.</div>
		</li>
		<li data-sub-note-item="3-11">
		<div class="lab-step">Check on the tubes every few minutes and record positive results as you see them. Note approximately how long it took for delayed positive results to appear.</div>
		</li>
		<li data-sub-note-item="3-12">
		<div class="lab-step">Once the tubes have sat for at least 15 min, you can assume that the results are final. Record the results for 1-butanol, 2-butanol, and for your unknown if applicable.</div>
		</li>
		<li data-sub-note-item="3-13">
		<div class="lab-step">Now, let&#39;s clean up. Your instructor will collect the Cr(VI) solutions, so leave any tubes of orange solution from the Jones test in your hood.</div>
		</li>
		<li data-sub-note-item="3-14">
		<div class="lab-step">Empty the other test tubes into the waste beaker and rinse them with deionized water. Pour the waste into the aqueous metal waste container using a funnel and rinse the beaker with deionized water.</div>
		</li>
		<li data-sub-note-item="3-15">
		<div class="lab-step">Now, wash your glassware as usual and dispose of used pipettes in the glass waste. Lastly, clean your hood and throw out any trash in the lab trash container.</div>
		</li>
	</ul>
	</li>
	<li data-note-item="4" data-parent-collapse="">Results<button class="expand">Expand</button>
	<p>Identify your unknown alcohol. The four possibilities are 1-propanol, 2-propanol, 2-methyl-2-butanol, and para-chlorophenol.</p>
	<ul class="lab-items">
		<li data-sub-note-item="4-2">
		<div class="lab-step">Consider the results of the ferric chloride test first. If the mixture with your unknown alcohol turned purple, like phenol did, your alcohol must be para-chlorophenol. If you saw a negative result, your unknown is one of the three aliphatic alcohols.</div>
		</li>
		<li data-sub-note-item="4-3">
		<div class="lab-step">Look at the results of the Jones test. If the mixture with the unknown alcohol turned green, the unknown could be primary or secondary. If the mixture with your unknown alcohol stayed orange, your unknown alcohol is tertiary. Therefore, a negative Jones result means that your alcohol must be 2-methyl-2-butanol.</div>
		</li>
		<li data-sub-note-item="4-4">
		<div class="lab-step">Lastly, look at the results of the Lucas test. If you had a negative result in the Jones test, you should also have seen an immediate positive result in the Lucas test. This confirms that your alcohol was tertiary. If your unknown had a positive result after a short delay, then your unknown alcohol is secondary, and therefore, must be 2-propanol. Finally, if your unknown had a negative result in the Lucas test, your alcohol is primary, and therefore, must be 1-propanol.</div>
		</li>
	</ul>
	</li>
</ol>

Identifying Alcohols: Ferric Chloride Test, Jones Test, and Lucas Test - Procedure

Alkollerin Tanımlanması

Source: Lara Al Hariri and Ahmed Basabrain at the University of Massachusetts Amherst, MA, USA

	Ferric Chloride Test for PhenolsExpand
	In this lab, you ...

Beer's Law

Beer-Lambert Law and Equilibrium Constant Determination - Procedure

Bira Yasası

Source: Smaa Koraym at Johns Hopkins University, MD, USA

	Lab Setup for Beer&#8217;s LawExpand
	In this lab, you will combine aqueous solutions of FeCl3 ...

Concentration Dependence

<p>Source: Smaa Koraym at Johns Hopkins University, MD, USA</p>
<ol class="note-items">
	<li data-note-item="1" data-parent-collapse="">Concentration Dependence<button class="expand">Expand</button>
	<p>In this experiment, you will combine varying concentrations of aqueous HCl and sodium thiosulfate to make solid sulfur, which rapidly gathers into opaque yellow particles at a certain sulfur concentration. Since the reaction solution starts clear and colorless, you can easily tell when it reaches that concentration.</p>
	<p>You&#39;ll use the same test tube and total volume each time, so it will take the same amount of sulfur to make each solution completely opaque. Thus, you&#39;ll measure the reaction progress by timing how long that takes. You&#39;ll then use that data to estimate the reaction orders of the individual reactants and of the overall reaction.</p>
	<p>Before starting the lab, make a table listing the reactant concentrations, the time to solution opacity, and the solution temperature for the trials.</p>
	<h4><strong>Table 1: Reaction progress</strong></h4>
	<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
		<tbody>
			<tr>
				<td><strong>Trial</strong></td>
				<td><strong>[Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub>] (M)</strong></td>
				<td><strong>[HCl] (M)</strong></td>
				<td><strong>Time (s)</strong></td>
				<td><strong>Temp (&#176;C)</strong></td>
			</tr>
			<tr>
				<td style="text-align: center;">1</td>
				<td style="text-align: center;">0.1 M</td>
				<td style="text-align: center;">3.0 M</td>
				<td></td>
				<td></td>
			</tr>
			<tr>
				<td style="text-align: center;">2</td>
				<td style="text-align: center;">0.1 M</td>
				<td style="text-align: center;">3.0 M</td>
				<td></td>
				<td></td>
			</tr>
			<tr>
				<td style="text-align: center;">3</td>
				<td style="text-align: center;">0.2 M</td>
				<td style="text-align: center;">3.0 M</td>
				<td></td>
				<td></td>
			</tr>
			<tr>
				<td style="text-align: center;">4</td>
				<td style="text-align: center;">0.15 M</td>
				<td style="text-align: center;">3.0 M</td>
				<td></td>
				<td></td>
			</tr>
			<tr>
				<td style="text-align: center;">5</td>
				<td style="text-align: center;">0.05 M</td>
				<td style="text-align: center;">3.0 M</td>
				<td></td>
				<td></td>
			</tr>
			<tr>
				<td style="text-align: center;">6</td>
				<td style="text-align: center;">0.1 M</td>
				<td style="text-align: center;">6.0 M</td>
				<td></td>
				<td></td>
			</tr>
			<tr>
				<td style="text-align: center;">7</td>
				<td style="text-align: center;">0.1 M</td>
				<td style="text-align: center;">4.5 M</td>
				<td></td>
				<td></td>
			</tr>
			<tr>
				<td style="text-align: center;">8</td>
				<td style="text-align: center;">0.1 M</td>
				<td style="text-align: center;">1.5 M</td>
				<td></td>
				<td></td>
			</tr>
		</tbody>
	</table>
	<p><a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/50/Table_1._Reaction_progress.xlsx" target="_blank">Click Here to download Table 1</a></p>
	<p>We want to make sure that the reactions are all taking place at room temperature. You&#39;ll perform two benchmark trials, three trials with different sodium thiosulfate concentrations, and three trials with different HCl concentrations. You will vary the concentrations by diluting stock solutions of sodium thiosulfate and HCl, as shown in the following tables.</p>
	<h4><strong>Table 2: Sodium thiosulfate dilutions</strong></h4>
	<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
		<tbody>
			<tr>
				<td style="text-align: center;"><strong>Target Concentration</strong></td>
				<td style="text-align: center;"><strong>Volume of 0.2 M sodium thiosulfate</strong></td>
				<td style="text-align: center;"><strong>Volume of DI water</strong></td>
			</tr>
			<tr>
				<td style="text-align: center;">0.05 M</td>
				<td style="text-align: center;">5 mL</td>
				<td style="text-align: center;">15 mL</td>
			</tr>
			<tr>
				<td style="text-align: center;">0.10 M</td>
				<td style="text-align: center;">10 mL</td>
				<td style="text-align: center;">10 mL</td>
			</tr>
			<tr>
				<td style="text-align: center;">0.15 M</td>
				<td style="text-align: center;">15 mL</td>
				<td style="text-align: center;">5 mL</td>
			</tr>
			<tr>
				<td style="text-align: center;">0.20 M</td>
				<td style="text-align: center;">20 mL</td>
				<td style="text-align: center;">0 mL</td>
			</tr>
		</tbody>
	</table>
	<p><a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/50/Table_2._Sodium_thiosulfate_dilutions.xlsx" target="_blank">Click Here to download Table 2</a></p>
	<h4><strong>Table 3: HCl Dilutions</strong></h4>
	<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
		<tbody>
			<tr>
				<td style="text-align: center;"><strong>Target Concentration</strong></td>
				<td style="text-align: center;"><strong>Volume of 6.0 M HCl</strong></td>
				<td style="text-align: center;"><strong>Volume of DI water</strong></td>
			</tr>
			<tr>
				<td style="text-align: center;">1.5 M</td>
				<td style="text-align: center;">2.5 mL</td>
				<td style="text-align: center;">7.5 mL</td>
			</tr>
			<tr>
				<td style="text-align: center;">3.0 M</td>
				<td style="text-align: center;">5.0 mL</td>
				<td style="text-align: center;">5.0 mL</td>
			</tr>
			<tr>
				<td style="text-align: center;">4.5 M</td>
				<td style="text-align: center;">7.5 mL</td>
				<td style="text-align: center;">2.5 mL</td>
			</tr>
			<tr>
				<td style="text-align: center;">6.0 M</td>
				<td style="text-align: center;">10 mL</td>
				<td style="text-align: center;">0 mL</td>
			</tr>
		</tbody>
	</table>
	<p><a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/50/Table_3._HCl_Dilutions.xlsx" target="_blank">Click Here to download Table 3</a></p>
	<p>Remember to use caution when handling HCl, which is toxic and highly corrosive. Sulfur dioxide, which is a gaseous product of this reaction, is also toxic. You will leave the reaction waste in the fume hood overnight to let the sulfur dioxide escape harmlessly.</p>
	<ul class="lab-items">
		<li data-sub-note-item="1-6">
		<div class="lab-step">First, put on a lab coat, splash-proof safety glasses, and nitrile gloves.</div>
		</li>
		<li data-sub-note-item="1-7">
		<div class="lab-step">Fill a plastic wash bottle with deionized water and get a test tube marked with an X.</div>
		</li>
		<li data-sub-note-item="1-8">
		<div class="lab-step">Clamp the test tube over the center of a small stir plate. The label must be on the opposite side from you. Make sure that you can clearly see the X. Place a small magnetic stir bar in the test tube.</div>
		</li>
		<li data-sub-note-item="1-9">
		<div class="lab-step">Use a thermometer clamp to secure a glass thermometer in the lower third of the tube, keeping it clear of the X and the stir bar.</div>
		</li>
		<li data-sub-note-item="1-10">
		<div class="lab-step">Cut a sheet of about 20 squares of plastic paraffin film from a roll and bring the sheet back to your hood.</div>
		</li>
		<li data-sub-note-item="1-11">
		<div class="lab-step">Lay paper towels in the fume hood as a clean surface for labware to be reused.</div>
		</li>
		<li data-sub-note-item="1-12">
		<div class="lab-step">Label a 600-mL beaker as &#8216;waste&#8217; for the reaction, a 100-mL beaker as &#8216;0.2 M sodium thiosulfate&#8217;, and a 50-mL beaker as &#8216;6 M HCl&#8217;.</div>
		</li>
		<li data-sub-note-item="1-13">
		<div class="lab-step">Fill the 100-mL beaker with 0.2 M sodium thiosulfate from the stock bottle in the dispensing hood.</div>
		</li>
		<li data-sub-note-item="1-14">
		<div class="lab-step">After that, bring the 50-mL beaker and a watch glass to the acid-dispensing hood to obtain 50 mL of 6 M HCl. Cover the filled beaker with the watch glass and bring your portion of HCl back to your hood.</div>
		</li>
		<li data-sub-note-item="1-15">
		<div class="lab-step">Prepare 20 mL of 0.1 M sodium thiosulfate for the first benchmark trial. Use a 10-mL volumetric pipette to measure 10 mL of 0.2 M sodium thiosulfate and dispense it into a 20-mL volumetric flask. Fill the 20-mL volumetric flask with deionized water to the mark.</div>
		</li>
		<li data-sub-note-item="1-16">
		<div class="lab-step">Then, cut a square of plastic paraffin film, seal the flask, and invert it several times to thoroughly mix the solution.</div>
		</li>
		<li data-sub-note-item="1-17">
		<div class="lab-step">Remove the film and pour the solution into the test tube.</div>
		</li>
		<li data-sub-note-item="1-18">
		<div class="lab-step">Prepare 10 mL of 3 M HCl. Pipette 5 mL of 6 M HCl into a 10-mL graduated cylinder. Add deionized water to fill the graduated cylinder to the 10-mL line.</div>
		</li>
		<li data-sub-note-item="1-19">
		<div class="lab-step">Seal the top of the graduated cylinder with plastic paraffin film and thoroughly mix the HCl solution by inverting it several times.</div>
		</li>
		<li data-sub-note-item="1-20">
		<div class="lab-step">Now, start the stir motor and get a reset stopwatch. Confirm that you can see the X through the solution in the test tube.</div>
		</li>
		<li data-sub-note-item="1-21">
		<div class="lab-step">Simultaneously start the stopwatch and pour the 3 M HCl into the test tube.</div>
		</li>
		<li data-sub-note-item="1-22">
		<div class="lab-step">Watch the X through the solution, which will start becoming cloudy when enough sulfur has been produced to saturate it. Stop the stopwatch exactly when the solution becomes so opaque that the X disappears.</div>
		</li>
		<li data-sub-note-item="1-23">
		<div class="lab-step">Record the time in your lab notebook for benchmark trial 1 and then reset the stopwatch. Also, record the temperature of the solution.</div>
		</li>
		<li data-sub-note-item="1-24">
		<div class="lab-step">Now, turn off the stir motor, remove the thermometer, and rinse it with deionized water into the waste beaker.</div>
		</li>
		<li data-sub-note-item="1-25">
		<div class="lab-step">Then, empty the test tube into the waste beaker, retrieve the stir bar with long forceps, and rinse the test tube and stir bar with deionized water.</div>
		</li>
		<li data-sub-note-item="1-26">
		<div class="lab-step">Thoroughly clean the test tube with a test tube brush. Briefly rinse the volumetric flask and graduated cylinder with deionized water as well. Dry everything with paper towels.</div>
		</li>
		<li data-sub-note-item="1-27">
		<div class="lab-step">Repeat the trial in the exact same way for the second benchmark time. If the time is not within 3 - 5 s of the first trial, repeat the benchmark trial until you have two consistent trials.</div>
		</li>
		<li data-sub-note-item="1-28">
		<div class="lab-step">Follow the same overall procedure for each subsequent trial, changing the dilutions as indicated in your table and cleaning your glassware between each trial. Use a 5-mL volumetric pipette as needed when measuring the sodium thiosulfate stock solution in trials four and five.</div>
		</li>
		<li data-sub-note-item="1-29">
		<div class="lab-step">Once you have performed all eight trials, rinse your glassware and tools one last time and neutralize the reaction waste with baking soda. Use caution because sulfur dioxide is one of the reaction products.</div>
		</li>
		<li data-sub-note-item="1-30">
		<div class="lab-step">Transfer the neutralized reaction waste to the designated waste container. Then, pour any remaining sodium thiosulfate solution into its labeled waste container and rinse the beaker with deionized water.</div>
		</li>
		<li data-sub-note-item="1-31">
		<div class="lab-step">Neutralize any remaining HCl with baking soda before flushing it down the drain with tap water.</div>
		</li>
		<li data-sub-note-item="1-32">
		<div class="lab-step">Finally, clean and put away your labware according to your standard practices and throw out any trash remaining in your hood. Your instructor will dispose of the reaction waste later.</div>
		</li>
	</ul>
	</li>
	<li data-note-item="2" data-parent-collapse="">Results<button class="expand">Expand</button>
	<ul class="lab-items">
		<li data-sub-note-item="2-1">
		<div class="lab-step">Now, estimate the reaction order of sodium thiosulfate and HCl. Calculate the starting concentration of sodium thiosulfate in the reaction mixture for trials 1 through 5. Looking at the concentration of sodium thiosulfate and the reaction times, we see that as the concentration doubles, the time to opacity is halved.
		<h4><strong>Table 4: Estimating reaction order sodium thiosulfate</strong></h4>
		<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
			<tbody>
				<tr>
					<td style="text-align: center;"><strong>Trial</strong></td>
					<td style="text-align: center;"><strong>[Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub>] added</strong></td>
					<td style="text-align: center;"><strong>Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub> volume (mL)</strong></td>
					<td style="text-align: center;"><strong>Total volume (mL)</strong></td>
					<td style="text-align: center;"><strong>[Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub>] in mixture </strong></td>
					<td style="text-align: center;"><strong>Time (s)</strong></td>
					<td style="text-align: center;"><strong>Inverse time (s<sup>-1</sup>)</strong></td>
				</tr>
				<tr>
					<td style="text-align: center;">1, 2</td>
					<td style="text-align: center;">0.1</td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
				</tr>
				<tr>
					<td style="text-align: center;">3</td>
					<td style="text-align: center;">0.2</td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
				</tr>
				<tr>
					<td style="text-align: center;">4</td>
					<td style="text-align: center;">0.15</td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
				</tr>
				<tr>
					<td style="text-align: center;">5</td>
					<td style="text-align: center;">0.05</td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
				</tr>
			</tbody>
		</table>
		<a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/50/Table_4._Estimating_reaction_order_sodium_thiosulfate.xlsx" target="_blank">Click Here to download Table 4</a></div>
		</li>
		<li data-sub-note-item="2-2">
		<div class="lab-step">Remember that each trial used the same volume, so it took the same amount of sulfur to make each solution opaque. Thus, the reaction is twice as fast when the sodium thiosulfate concentration is doubled.</div>
		</li>
		<li data-sub-note-item="2-3">
		<div class="lab-step">When the concentration increases by a factor of 4, the reaction rate also increases by a factor of 4. This one-to-one relationship suggests that the reaction was first order for sodium thiosulfate. If so, we would expect a plot of rate versus sodium thiosulfate concentration to be linear.</div>
		</li>
		<li data-sub-note-item="2-4">
		<div class="lab-step">We didn&#39;t measure how much sulfur it took to turn the solution opaque, but we assume that it was the same for each trial. This lets us use the inverse of time to opacity as a stand-in for the rate. The slope won&#39;t be equal to k, but that&#39;s OK for this lab.</div>
		</li>
		<li data-sub-note-item="2-5">
		<div class="lab-step">Plot inverse reaction time as a function of sodium thiosulfate concentration. This confirms the linear relationship between sulfur production and thiosulfate concentration. Thus, the reaction seems to be first order with respect to thiosulfate.</div>
		</li>
		<li data-sub-note-item="2-6">
		<div class="lab-step">Use the same method to estimate the reaction order of HCl. First, calculate the starting concentration of HCl in the benchmark trials and in trials 6 through 8.
		<h4><strong>Table 5: Estimating reaction order HCl</strong></h4>
		<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
			<tbody>
				<tr>
					<td style="text-align: center;"><strong>Trial</strong></td>
					<td style="text-align: center;"><strong>[HCl] added</strong></td>
					<td style="text-align: center;"><strong>HCl volume (mL) </strong></td>
					<td style="text-align: center;"><strong>Total volume (mL) </strong></td>
					<td style="text-align: center;"><strong>[HCl] in mixture </strong></td>
					<td style="text-align: center;"><strong>Time (s)</strong></td>
				</tr>
				<tr>
					<td style="text-align: center;">1, 2</td>
					<td style="text-align: center;">0.1</td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
				</tr>
				<tr>
					<td style="text-align: center;">3</td>
					<td style="text-align: center;">0.2</td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
				</tr>
				<tr>
					<td style="text-align: center;">4</td>
					<td style="text-align: center;">0.15</td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
				</tr>
				<tr>
					<td style="text-align: center;">5</td>
					<td style="text-align: center;">0.05</td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
					<td style="text-align: center;"></td>
				</tr>
			</tbody>
		</table>
		<a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/50/Table_5._Estimating_reaction_order_HCl.xlsx" target="_blank">Click Here to download Table 5</a></div>
		</li>
		<li data-sub-note-item="2-7">
		<div class="lab-step">Then, look at the concentration of HCl and the reaction times for these trials. The reaction times are nearly identical, so the HCl concentration has no effect on the reaction rate. This means that HCl seems to be zeroth order for this reaction.</div>
		</li>
		<li data-sub-note-item="2-8">
		<div class="lab-step">Lastly, add up the reaction orders of the reactants to get the overall reaction order.</div>
		</li>
	</ul>
	</li>
</ol>

Concentration Dependence and Reaction Order - Procedure

Konsantrasyon Bağımlılığı

Source: Smaa Koraym at Johns Hopkins University, MD, USA

	Concentration DependenceExpand
	In this experiment, you will combine varying concentrations of ...

Optimal Foraging

<ol class="note-items"><li data-note-item="1" data-parent-collapse="">Simulating Foraging with Artificial Habitats and Prey
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="1-1"><div class="lab-step">NOTE: The foragers will hunt for prey represented by pinto beans in four buckets of rice with varying prey densities. Without knowing what these densities are, foragers must obtain as many prey items as possible in as little time as possible. 
</div></li><li data-sub-note-item="1-2"><div class="lab-step">HYPOTHESES: In this experiment, the experimental hypothesis could be that foragers will catch the most prey in the higher prey density bucket and also spend the most time foraging there.  The null hypothesis would then be that foragers will catch an equal number of prey in each bucket and that foragers will spend an equal amount of time foraging in each patch. 
</div></li><li data-sub-note-item="1-3"><div class="lab-step">To begin the foraging activity, record the names and role of each participant at the top of the student data collection sheet.  NOTE: Before starting the experiment, the forager is allowed to become familiar with the foraging process &#8211; the following steps are a practice round. 
</div></li><li data-sub-note-item="1-4"><div class="lab-step">The forager should kneel or sit in front of the average density bucket. 
</div></li><li data-sub-note-item="1-5"><div class="lab-step">Once the timer says start, the forager may begin looking for the pinto beans representing the prey. The forager can spend as much time as they like foraging in this bucket. 
</div></li><li data-sub-note-item="1-6"><div class="lab-step">Once a prey item is located, the forager must signal that one has been found and place the prey in the cup next to the bucket.
</div></li><li data-sub-note-item="1-7"><div class="lab-step">Once they believe they have acquired most of the prey in the patch, they should tell the timer to stop the time and the practice round is over. 
</div></li><li data-sub-note-item="1-8"><div class="lab-step">To begin the simulation proper, the forager should sit or kneel in front of bucket A. 
</div></li><li data-sub-note-item="1-9"><div class="lab-step">The timer must be ready to start the stopwatch. 
</div></li><li data-sub-note-item="1-10"><div class="lab-step">The recorder should be ready to record the time each prey item is located, in addition to the time that the forager arrived at and left each bucket. 
</div></li><li data-sub-note-item="1-11"><div class="lab-step">When all parties are ready, the timer should start the stopwatch and say &#8220;start&#8221;,  and the forager should begin foraging. NOTE: The stopwatch will run through the rest of the round for buckets B and C.
</div></li><li data-sub-note-item="1-12"><div class="lab-step">As the forager signals finding pinto beans and places them in the cup next to the bucket, the timer should tell the recorder the time.
</div></li><li data-sub-note-item="1-13"><div class="lab-step">The recorder should then write the time in the student data collection sheet.  <a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/34/Table_1_Optimal_foraging.xlsx" style="display:block;margin:20px;" target="_blank">Click Here to download Table 1</a>
</div></li><li data-sub-note-item="1-14"><div class="lab-step">Once the forager has decided to move on to the next bucket, they should tell the timer &#8220;done&#8221;, and begin moving to the next patch. 
</div></li><li data-sub-note-item="1-15"><div class="lab-step">The recorder should record the time the forager left and the time they arrived at bucket B in the student data collection sheet.
</div></li><li data-sub-note-item="1-16"><div class="lab-step">Repeat the same procedure for buckets B and C. Once the forager has completed the activity, it is time for the next forager to begin using the same procedure. 
</div></li></ul></li><li data-note-item="2" data-parent-collapse="">Results
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="2-1"><div class="lab-step">Before performing any data analysis, review the data collection sheet and compile your individual data for captured prey, foraging time, and travel time for each bucket in your student calculations table. <a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/34/Table_2_Optimal_foraging.xlsx" style="display:block;margin:20px;" target="_blank">Click Here to download Table 2</a>
</div></li><li data-sub-note-item="2-2"><div class="lab-step">After this, calculate your individual capture rate for each bucket by dividing the number of prey captured by the sum of the foraging time and travel time and record these values in your table. Individual capture rate =  Number of prey captured / (foraging time + travel time)
</div></li><li data-sub-note-item="2-3"><div class="lab-step">To calculate your Giving-Up-Time or a GUT for each bucket, subtract the time that the last prey item was acquired from the time you left the bucket.  GUT = time forager left bucket  -  time last prey item acquired
</div></li><li data-sub-note-item="2-4"><div class="lab-step">Next, calculate the mean GUT for your foraging group and record the values in your table.
</div></li><li data-sub-note-item="2-5"><div class="lab-step">Finally, calculate your scaled GUT for each bucket by dividing the bucket GUT by your group&#39;s mean GUT. Scaled GUT =  Bucket GUT / Group mean GUT NOTE: The scaled GUT will allow class data to be pooled later on without differences in individual foragers skewing the data. 
</div></li><li data-sub-note-item="2-6"><div class="lab-step">The instructor should now compile the data into the classroom spreadsheet.  <a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/34/Table_3_Optimal_foraging.xlsx" style="display:block;margin:20px;" target="_blank">Click Here to download Table 3</a>
</div></li><li data-sub-note-item="2-7"><div class="lab-step">Plot a bar graph of the average number of prey collected in each bucket. On the x-axis, A should represent the low prey density bucket, B should represent the medium prey density bucket, and C the high prey density bucket. Plot the y-axis as the number of prey items caught. 
</div></li><li data-sub-note-item="2-8"><div class="lab-step">Next, plot the graph of the class average scaled GUT, where the x-axis represents the buckets with varying levels of prey density and the y-axis shows the values for the average scaled GUT. 
</div></li><li data-sub-note-item="2-9"><div class="lab-step">Plot a third graph of the average time spent foraging in each bucket. 
</div></li><li data-sub-note-item="2-10"><div class="lab-step">Now review the Marginal Value Theorem (MVT) from the concepts video and examine the three graphs that you generated from your class data. Take note of whether the graphs conform to the predictions of MVT. 
</div></li></ul></li></ol>

Optimal Foraging: Foraging with Artificial Habitats and Prey - Procedure

Optimal Yiyecek Arama

Simulating Foraging with Artificial Habitats and Prey
ExpandNOTE: The foragers will hunt for prey represented by pinto beans in four buckets of rice with ...

Biyoloji

Ekoloji

Group Behavior

<ol class="note-items"><li data-note-item="1" data-parent-collapse="">The Hawk-Dove Game
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="1-1"><div class="lab-step">NOTE: In this activity, you will play the hawk and dove game with a single partner and then with multiple partners to observe hypothetical costs and benefits of the antagonist or cooperative behavior respectively. 
</div></li><li data-sub-note-item="1-2"><div class="lab-step">Before the activity starts, review the cost-benefit table so that you understand how to score the game. <a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/33/Table_1_Group_behavior.xlsx" style="display:block;margin:20px;" target="_blank">Click Here to download Table 1</a>
</div></li><li data-sub-note-item="1-3"><div class="lab-step">HYPOTHESES: The experimental hypothesis for this exercise could be that the dove strategy will become more frequent between repeated partners, and the hawk strategy will become more frequent when interactions are with a variety of partners. The null hypothesis could be that there will be no change in strategy over time with repeat or different partner combinations. NOTE: Benefit can be determined by looking at the left column and choosing the row that corresponds to the card you played. The box that corresponds to the choice of your partner can be found in the top row. For the purposes of this game, B equals four and C equals three. So depending on the cards played, player one here, which is you, would gain a score of two, four, zero or one half. 
</div></li><li data-sub-note-item="1-4"><div class="lab-step">Collect a set of two game cards. 
</div></li><li data-sub-note-item="1-5"><div class="lab-step">Take out the cards labeled hawk and dove and place them face down on the table or conceal them in your hands. 
</div></li><li data-sub-note-item="1-6"><div class="lab-step">When the instructor gives the signal show either of the two cards to the student sitting across from you. Try to strategize how to receive the highest benefit from every interaction on your own but do not communicate with your partner. 
</div></li><li data-sub-note-item="1-7"><div class="lab-step">In the Single Partner Recording Table (Table 2) provided by your instructor, note the cards played as well as the benefit you received for that round.
</div></li><li data-sub-note-item="1-8"><div class="lab-step">Repeat showing cards to the same partner and determining benefit on your instructor&#39;s signal for a total of 15 rounds.
</div></li><li data-sub-note-item="1-9"><div class="lab-step">At the end of those rounds, the student with the highest total benefit value was determined to be the &#8220;winner&#8221;, or the most fit.
</div></li><li data-sub-note-item="1-10"><div class="lab-step">As a class, determine the percentages of hawks and doves played as well as the average benefit received for each round, using this formula: Class average benefit=(sum total benefit)/(number of players)
</div></li><li data-sub-note-item="1-11"><div class="lab-step">For the second game, and then for each round of play, one row of students should rotate to their right, leaving all players with a new partner.
</div></li><li data-sub-note-item="1-12"><div class="lab-step">Continue playing for 15 rounds or until students end up back in their starting positions, recording the data in the Multiple Partner Recording Table (Table 3) given to you by your instructor.
</div></li><li data-sub-note-item="1-13"><div class="lab-step">For each round, determine the percentages of hawks and doves played that round, as well as the average benefit received.
</div></li></ul></li><li data-note-item="2" data-parent-collapse="">Cheating and Cooperation Exercise
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="2-1"><div class="lab-step">NOTE: In this activity, you will exchange benefits, represented by colored or similar items, with your classmates. In this simulation, a cheater is defined as a person who gives fewer benefits than they receive. During this activity, you will observe the frequency of cheating behavior over time. 
</div></li><li data-sub-note-item="2-2"><div class="lab-step">HYPOTHESES: The experimental hypothesis is that cheaters will receive fewer benefits over time and cooperators will continue to provide equal benefits to one another. The null hypothesis is that the frequency of cheaters and cooperators does not change over time. 
</div></li><li data-sub-note-item="2-3"><div class="lab-step">Each person should collect beads of one color to represent a tangible benefit, as well as one paper bag and a three-ring binder.
</div></li><li data-sub-note-item="2-4"><div class="lab-step">Get into a group of three so that all members have objects of the same color.
</div></li><li data-sub-note-item="2-5"><div class="lab-step">Now find another group with a different color to pair with. In each round, partners will exchange benefits without knowing what they are receiving from their partner and without discussion within their group.  NOTE: Benefits of a different color from your starting color are worth twice as much.
</div></li><li data-sub-note-item="2-6"><div class="lab-step">Turn face to face with a member from the other group while still being able to conceal the objects in your possession.  TIP:<strong> </strong>Setting up a screen using a notebook or sitting behind a desk can be helpful here.
</div></li><li data-sub-note-item="2-7"><div class="lab-step">When given a signal from the instructor, place zero to two benefits into the paper bag and pass it to your partner.
</div></li><li data-sub-note-item="2-8"><div class="lab-step">Simultaneously, receive the bag from your partner and then remove the benefits from the bag.
</div></li><li data-sub-note-item="2-9"><div class="lab-step">Make a note of how many benefits you gave away and how many you received in the Cheating and Cooperation Table (Table 4) provided by your instructor.
</div></li><li data-sub-note-item="2-10"><div class="lab-step">Turn to a new member from the other group and repeat the exchange.
</div></li><li data-sub-note-item="2-11"><div class="lab-step">Rotate through all of the members of the other group for as many rounds as the instructor determines - which will not be revealed until the game ends so as not to alter player behavior.
</div></li><li data-sub-note-item="2-12"><div class="lab-step">Once the game has ended, note for each round in the cheating and cooperation table whether you gave more than your partner, received more from them or if you gave the same amount.
</div></li><li data-sub-note-item="2-13"><div class="lab-step">Now total up all of the benefits in your possession, with benefits you&#39;ve received from the other group being worth twice as much.
</div></li><li data-sub-note-item="2-14"><div class="lab-step">For each round, the whole class should total up the number of cheaters - with cheaters defined as those who gave less than they received.
</div></li></ul></li><li data-note-item="3" data-parent-collapse="">Results
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="3-1"><div class="lab-step">For both the single partner hawk-dove game and the multiple partners hawk-dove game, use the whole class data to plot the percentages as two separate lines - one for the percentage of hawks, and one for the percentage of doves, for each of the 15 rounds.
</div></li><li data-sub-note-item="3-2"><div class="lab-step">Take note of whether the cards played changed as more rounds were played.
</div></li><li data-sub-note-item="3-3"><div class="lab-step">Manipulate the values for B and C to see if you can find the point at which values of B and C would render the hawk strategy no longer effective (this would be the point when there is no benefit to choosing the hawk strategy over always choosing the dove strategy).
</div></li><li data-sub-note-item="3-4"><div class="lab-step">As a class, use the data from the cheating and cooperation activity to make a graph showing the percentage of rounds each individual player cheated versus the amount of benefits they ended with.
</div></li><li data-sub-note-item="3-5"><div class="lab-step">Consider whether it is better to be a cheater or a cooperator in this scenario and discuss as a class what makes this scenario different from the hawk-dove game.
</div></li><li data-sub-note-item="3-6"><div class="lab-step">Now, use the class data to graph the percentage of cheaters against the number of rounds, and look for any trends over time.
</div></li><li data-sub-note-item="3-7"><div class="lab-step">Consider which type of strategy would most likely evolve in a setting where partners interact repeatedly.
</div></li><li data-sub-note-item="3-8"><div class="lab-step">Then, note which tactic might be beneficial for a species that relies on cooperation. 
</div></li><li data-sub-note-item="3-9"><div class="lab-step">Discuss as a class what would likely happen if you increased or decreased the relative value of the benefits you receive.
</div></li></ul></li></ol>

Group Behavior: Hawk-Dove Game and Trading Exercise - Procedure

Grup Davranışı

The Hawk-Dove Game
ExpandNOTE: In this activity, you will play the hawk and dove game with a single partner and then with multiple partners to observe ...

Hardy-Weinberg and Genetic Drift

<ol class="note-items"><li data-note-item="1" data-parent-collapse="">Class Simulation
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="1-1"><div class="lab-step">Begin by opening a new spreadsheet file. Following the Hardy-Weinberg equation where p is the frequency of a dominant allele A in a population, and q is defined as the frequency of a recessive allele B, input frequency p of allele A into cell B2, and frequency q of allele B into cell B3.
</div></li><li data-sub-note-item="1-2"><div class="lab-step">Assign the value 0.5 to cell C2.
</div></li><li data-sub-note-item="1-3"><div class="lab-step">Following the 1 &#8211; p = q equation, enter the formula &#8220;= 1 &#8211; C2&#8221; into cell C3 to calculate the frequency q of allele B. NOTE: Cells C2 and C3 will represent the gene pool used in the next few steps.
</div></li><li data-sub-note-item="1-4"><div class="lab-step">Label cells E2 and F2 &#8220;Allele 1&#8221; and &#8220;Allele 2&#8221; respectively, then enter the RAND code for random formula into cell E3. =IF (RAND()</div></li><li data-sub-note-item="1-5"><div class="lab-step">Select cell E3 and drag the bottom right corner of the cell down to E27 to duplicate the formula into 25 cells, creating an allele for the other offspring, and enter the same formula that was used in cell E3 into cell F3.
</div></li><li data-sub-note-item="1-6"><div class="lab-step">Add a third column of data starting with the description &#8220;Genotype&#8221; in cell G2, and add the CONCATENATE function to cell G3 to combine the two randomly generated alleles and to create a genotype.
</div></li><li data-sub-note-item="1-7"><div class="lab-step">Drag this formula down for 25 cells and label cells H2, I2, and J2 AA, AB, and BB respectively.
</div></li><li data-sub-note-item="1-8"><div class="lab-step">Then, input one IF function as shown here into cells H3, I3, and J3. Drag the formulas down for 25 rows per column. The formulas will return a 1 if the genotype in this row matches the genotype in the header row, and a 0 if the genotype in this row is one of the other two genotypes. H3: = IF (G3=&#8221;AA&#8221;,1,0) I3: =IF(OR(G3=&#8221;AB,G3=&#8221;BA&#8221;),1,0) J3: =IF(G3=&#8221;BB&#8221;,1,0)
</div></li><li data-sub-note-item="1-9"><div class="lab-step">Then, label cell D28 as &#8220;SUM&#8221;, add the formula to cell H28, and drag the formula to cells I28 and J28 to get the total number of each genotype.
</div></li><li data-sub-note-item="1-10"><div class="lab-step">Next, label cells H30 and J30 &#8220;A&#8221; and &#8220;B&#8221; respectively and label cell D31 &#8220;Number of alleles&#8221;.
</div></li><li data-sub-note-item="1-11"><div class="lab-step">Add code to cells H31 and J31 to obtain the total number of alleles in the simulated generation, which is two times the frequency of the respective homozygous genotype, plus the frequency of the heterozygous genotype.
</div></li><li data-sub-note-item="1-12"><div class="lab-step">Then, label cell E32 &#8220;Next gen allele frequency&#8221; and add code to cells H32 and J32 to obtain the ratio of alleles in the next generation.
</div></li><li data-sub-note-item="1-13"><div class="lab-step">Using the gene frequencies generated in the mathematical model you just built, adjust the gene pool values in cells C2 and C3 to those from H32 and J32, and run 10 more generations, updating the gene pool with the resulting allele frequency each time.
</div></li><li data-sub-note-item="1-14"><div class="lab-step">Record the ratio of the two variables at each time point in the spreadsheet on the table, and create a line graph to see how a small population changes over time. Hypotheses: The experimental hypothesis in this study is that smaller populations will deviate more from the Hardy-Weinberg expected frequencies of the alleles than will larger populations, because smaller populations are more susceptible to genetic drift. The null hypothesis is that the allele frequencies within the populations will not differ from the Hardy-Weinberg equilibrium equation expected frequencies, meaning that the allele frequencies will be the same from generation to generation.
</div></li><li data-sub-note-item="1-15"><div class="lab-step">Set the frequency of gene A to 0.3 and gene B to 0.7, and run the model 10 more times, recording the ratio of the genes in the next generation in the table after each run.
</div></li><li data-sub-note-item="1-16"><div class="lab-step">Then, drag the formulas for the cells further down to alter the model to include 100 zygotes and run the model another 10 times.
</div></li><li data-sub-note-item="1-17"><div class="lab-step">After the last run, save all of the working data to a personal storage device and exit the spreadsheet program.
</div></li></ul></li><li data-note-item="2" data-parent-collapse="">Simulation for Hardy-Weinberg and Genetic Drift
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="2-1"><div class="lab-step">To begin, find a partner and then collect one bag from the instructor.
</div></li><li data-sub-note-item="2-2"><div class="lab-step">Verify that the bag contains beads of two different colors and an even number of each color. 
</div></li><li data-sub-note-item="2-3"><div class="lab-step">Designate one color as allele capital A and the other as small a. Hypotheses: The experimental hypothesis for this simulation is that allele frequencies will not change over the 10 generations of the experiment, and Hardy-Weinberg equilibrium will be observed. The null hypothesis is that equilibrium will not be seen in the population.
</div></li><li data-sub-note-item="2-4"><div class="lab-step">Note the initial frequency in Table 1 next to generation zero. Using the Hardy-Weinberg equation, calculate the initial genotype frequencies of the population and note this in Table 1. <a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/4/Lab_4_Table_A.xlsx" target="__blank" style="display:block;margin:20px;">Click Here to download Table A</a>
</div></li><li data-sub-note-item="2-5"><div class="lab-step">Then, discuss with your partner about the expected final allele and genotype frequencies after 10 generations of Hardy-Weinberg equilibrium. Note this next to prediction in Table 1.
</div></li><li data-sub-note-item="2-6"><div class="lab-step">Draw a pair of beads from the bag. This represents the genotype of one individual in the next generation.
</div></li><li data-sub-note-item="2-7"><div class="lab-step">Place a tally mark in the appropriate column next to Generation 1.
</div></li><li data-sub-note-item="2-8"><div class="lab-step">Now, keeping each pair of beads out of the bag every time, repeat the drawing 20 times to fill out the generation one row of Table 1.
</div></li><li data-sub-note-item="2-9"><div class="lab-step">Using the tallies, calculate the allele frequency for that generation, remembering to count both alleles in each genotype. Make a note of the new allele frequency, and then adjust the 100 beads to reflect the population after Generation 1 by adding and removing beads as necessary.
</div></li><li data-sub-note-item="2-10"><div class="lab-step">Repeat the drawing of pairs from this adjusted population for another generation of 20 picks, recording all of the observations in Table 1.
</div></li><li data-sub-note-item="2-11"><div class="lab-step">After calculating the allele frequency for this generation, adjust the population again to set up a third generation draw.
</div></li><li data-sub-note-item="2-12"><div class="lab-step">Keep drawing, calculating allele frequencies, and adjusting the starting population until 10 generations have been recorded in total.
</div></li></ul></li><li data-note-item="3" data-parent-collapse="">Violations of Hardy-Weinberg 
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="3-1"><div class="lab-step">To test the effect of different physical and ecological scenarios on the Hardy-Weinberg equilibrium, first draw a slip of paper to determine which Hardy-Weinberg assumption you will be testing.
</div></li><li data-sub-note-item="3-2"><div class="lab-step">Make a prediction of what you think might happen in your selected scenario before beginning the experiment, and record this on the board.
</div></li><li data-sub-note-item="3-3"><div class="lab-step">If you selected the mutation scenario, select 5 alleles at random from the set and replace them with 5 of a third color, allele capital B.
</div></li><li data-sub-note-item="3-4"><div class="lab-step">As before, perform the simulation by pulling pairs of beads from the bag for a generation of 20 picks, recording the results.  <a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/4/Lab_4_Table_B.xlsx" style="display:block;margin:20px;" target="__blank">Click Here to download Table B</a>
</div></li><li data-sub-note-item="3-5"><div class="lab-step">After each generation, make adjustments to have the starting population match the new allele frequency as before.
</div></li><li data-sub-note-item="3-6"><div class="lab-step">Then, replace 5 random alleles again with the new color, and simulate the new generation for 20 picks.
</div></li><li data-sub-note-item="3-7"><div class="lab-step">If you picked the non-random mating test, draw 1 allele at a time instead of 2 and then pair it with another of the same color pulled from the bag.
</div></li><li data-sub-note-item="3-8"><div class="lab-step">As with the previous simulation, adjust the population to match the new allele frequencies at the end of the previous generation, and carry out the simulation for 10 generations in total.
</div></li><li data-sub-note-item="3-9"><div class="lab-step">For the gene flow condition, begin by removing 10 alleles from the population and replacing them with 10 randomly selected alleles from another set of 100 beads.
</div></li><li data-sub-note-item="3-10"><div class="lab-step">Adjust the allele frequency and repeat the gene flow of removing 10 beads and adding 10 beads from another bag at the beginning of each generation.
</div></li><li data-sub-note-item="3-11"><div class="lab-step">If you drew small population size, simply start each generation with 60 alleles instead of 100.
</div></li><li data-sub-note-item="3-12"><div class="lab-step">As usual, adjust allele frequencies each generation and record 10 generations. In the selection condition, draw from the original bag of beads but do not count any homozygous recessive pairs that are drawn when calculating the allele frequency at the end of each generation.
</div></li></ul></li><li data-note-item="4" data-parent-collapse="">Simulation of Genetic Drift
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="4-1"><div class="lab-step">Make your predictions before running the simulations and record them on the board.
</div></li><li data-sub-note-item="4-2"><div class="lab-step">If you have the small population size test, run the standard Hardy-Weinberg simulation as before, but instead start each generation with 30 alleles and not 100.
</div></li><li data-sub-note-item="4-3"><div class="lab-step">If you drew the founder effect with two alleles test, start generation 1 by drawing only 5 pairs of beads from the bag.
</div></li><li data-sub-note-item="4-4"><div class="lab-step">Then, creating the gene pool for generation 2, include only 50 beads at the allele frequency determined in generation 1. When you create the gene pool for generation 3 and all subsequent generations, include 100 beads.
</div></li><li data-sub-note-item="4-5"><div class="lab-step">For a founder effect with 10 alleles, you will need to collect a bag containing random amounts of 10 different colored beads.
</div></li><li data-sub-note-item="4-6"><div class="lab-step">Designate an allele name for each of the new alleles, and then calculate their initial allele frequency.
</div></li><li data-sub-note-item="4-7"><div class="lab-step">Now, run the experiment in the same way as the founder effect with two alleles, by drawing just 5 pairs randomly for generation 1 and then creating the second generation with 50 alleles, and third and subsequent generations with 100. <a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/4/Lab_4_Table_C.xlsx" style="display:block;margin:20px;" target="__blank">Click Here to download Table C</a>
</div></li><li data-sub-note-item="4-8"><div class="lab-step">If you have the natural disaster with 2 alleles, you will need to collect a paper plate from your instructor.
</div></li><li data-sub-note-item="4-9"><div class="lab-step">Draw a line down the middle of the plate. Before generation 1, pour out all of the beads from a standard 100 bead setup onto the plate, and mix them randomly, spreading them evenly.
</div></li><li data-sub-note-item="4-10"><div class="lab-step">Choose one side of the plate and take all of the beads from that side. You should draw from these to create generation 1.
</div></li><li data-sub-note-item="4-11"><div class="lab-step">For generation 2 and beyond, adjust the population and use a total of 100 beads.
</div></li><li data-sub-note-item="4-12"><div class="lab-step">Finally, if you selected the natural disaster with 10 alleles test, you will need to collect a bag containing 10 different colored beads.
</div></li><li data-sub-note-item="4-13"><div class="lab-step">Assign a name to each new allele, and then place them on the plate and select half. Draw from these 50 beads for generation 1, and then calculate the allele frequencies to make a population of 100 in each subsequent round.
</div></li></ul></li><li data-note-item="5" data-parent-collapse="">Results
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="5-1"><div class="lab-step">Using the entered functions, calculate the number of each allele by multiplying the number of the homozygous genotypes by 2 and adding the number of the heterozygous genotypes.
</div></li><li data-sub-note-item="5-2"><div class="lab-step">The frequency can then be calculated by dividing the number of the allele in question by the total number of alleles. Enter the results into the table.
</div></li><li data-sub-note-item="5-3"><div class="lab-step">Next, use the Hardy-Weinberg equation to calculate the expected genotype frequency of the next generation, and compare the results of the simulation with the expected frequency, using the table as a guide.
</div></li><li data-sub-note-item="5-4"><div class="lab-step">Plot the changes of the population gene frequencies over time that you recorded in the table. Note any changes in allele frequencies over time and if any alleles decrease in frequency to the point that they disappear from the population. 
</div></li><li data-sub-note-item="5-5"><div class="lab-step">Plot the changes in the populations of the 25 and 100 zygotes with initial gene frequencies of 0.5 for each allele. Compare the results of the smaller population and the larger populations.  NOTE: The observed allele frequencies are expected to differ slightly from the Hardy-Weinberg expected values as a result of chance from the RAND function.
</div></li><li data-sub-note-item="5-6"><div class="lab-step">Using separate lines for each allele, graph the allele frequencies found for the original Hardy-Weinberg experiment over 10 generations.
</div></li><li data-sub-note-item="5-7"><div class="lab-step">Compare the results across the class, and see if your results agree.
</div></li><li data-sub-note-item="5-8"><div class="lab-step">Next, again using one line per allele, graph the results of your second experiment testing violations of the Hardy-Weinberg equilibrium, and share your finding with the class. Compare your actual results with your prediction. 
</div></li><li data-sub-note-item="5-9"><div class="lab-step">Finally, graph the results of your genetic drift simulation scenario in the same manner.
</div></li><li data-sub-note-item="5-10"><div class="lab-step">Again, present your results to the group and hypothesize why your results did or did not match your prediction. Compare your results to those of your classmates&#8217;. 
</div></li></ul></li></ol>

Hardy-Weinberg Equilibrium Principle and Genetic Drift - Procedure

Hardy-Weinberg ve Genetik Sürüklenme

Class Simulation
ExpandBegin by opening a new spreadsheet file. Following the Hardy-Weinberg equation where p is the frequency of a dominant allele A in a ...

Evrim

Animal Behavior

<ol class="note-items"><li data-note-item="1" data-parent-collapse="">Making Choice Chambers
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="1-1"><div class="lab-step">Before beginning the experiments, use one of the Sharpies from the lab table to trace a line around the circumference of the bottom of both bottles. One line should be 1 cm from the base of the bottle and the other should be 1.5 cm from the base of the bottle.
</div></li><li data-sub-note-item="1-2"><div class="lab-step">Use a razor blade to make a small cut in each bottle at the mark. 
</div></li><li data-sub-note-item="1-3"><div class="lab-step">Then, insert the scissors and carefully cut along the line until the bottoms of the bottles are removed completely.
</div></li><li data-sub-note-item="1-4"><div class="lab-step">Fit one bottle bottom into the other.
</div></li><li data-sub-note-item="1-5"><div class="lab-step">Tape the bottles together to make a secure chamber.
</div></li><li data-sub-note-item="1-6"><div class="lab-step">Use the razor blade and scissors to poke a hole into the center of the chamber. 
</div></li><li data-sub-note-item="1-7"><div class="lab-step">Take a piece of tape and fold the edge onto itself to make a tab and place the tape over the hole.  Note: The tab helps with easy removal and reattachment of the tape to the chamber.
</div></li><li data-sub-note-item="1-8"><div class="lab-step">Use the Sharpie to label one side of the chamber A and the other side B.
</div></li><li data-sub-note-item="1-9"><div class="lab-step">Upon receiving the colony of <em>Drosophila</em>, perform a count to make sure there are 40 living individuals in the vial.
</div></li></ul></li><li data-note-item="2" data-parent-collapse="">Geotaxis
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="2-1"><div class="lab-step">To perform a geotaxis assay, first attach a clean, empty bottle cap to each end of the choice chamber and turn the fly vial upside down onto its lid.
</div></li><li data-sub-note-item="2-2"><div class="lab-step">Open the tape flap in the center of the choice chamber.
</div></li><li data-sub-note-item="2-3"><div class="lab-step">Insert the funnel into the hole and tap all of the flies into the chamber. HYPOTHESES: The alternate hypothesis is that more flies will be moving against gravity, or up, regardless of the orientation of the choice chamber. Alternatively, if the flies are positively geotactic, then more flies will move down, or with gravity. The null hypothesis is that the flies will have no preference with regard to gravity and will move randomly within the chamber. 
</div></li><li data-sub-note-item="2-4"><div class="lab-step">Once the <em>Drosophila</em> are in the chamber, close the tape flap, rotate the chamber so that it stands vertically with side A on the bottom, and start the timer.
</div></li><li data-sub-note-item="2-5"><div class="lab-step">Immediately, count the number of <em>Drosophila</em> that are moving up and the number that are moving down. Record these data for time point 0 in the table. 
</div></li><li data-sub-note-item="2-6"><div class="lab-step">After 30 seconds, rotate the chamber so that side B is on the bottom and count the number of <em>Drosophila</em> that are moving up or down. Record these data for time point 30 in the table.
</div></li><li data-sub-note-item="2-7"><div class="lab-step">After 60 seconds, rotate the chamber so that side A is on the bottom again and record the number of moving flies for time point 60.  <a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/15/Table_1_Animal_behavior.xlsx" style="display:block;margin:20px;" target="__blank">Click Here to download Table 1</a>
</div></li><li data-sub-note-item="2-8"><div class="lab-step">Hold the chamber over the fly vial and carefully open the cap to return all of the <em>Drosophila</em> back to their empty vial. 
</div></li></ul></li><li data-note-item="3" data-parent-collapse="">Phototaxis
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="3-1"><div class="lab-step">To perform a phototaxis analysis, first cover side A of the choice chamber with tin foil, taking care that the foil reaches to the exact center between the two sides. 
</div></li><li data-sub-note-item="3-2"><div class="lab-step">Ensure the caps are secured on both ends of the chamber.  HYPOTHESES: In this exercise, the alternative hypothesis is that more flies will be found in the light side of the choice chamber, if the flues are attracted to light, or on the dark side if they are repelled by light. The null hypothesis is that <em>Drosophila</em> will have no preference with regard to either stimulus. Therefore, equal numbers of flies will be found on either side of the choice chamber.
</div></li><li data-sub-note-item="3-3"><div class="lab-step">Open the tape flap in the center of the choice chamber, insert the funnel into the hole, and tap all 40 flies into the chamber as previously described.
</div></li><li data-sub-note-item="3-4"><div class="lab-step">Set the timer to sound an alarm at 10 minutes.
</div></li><li data-sub-note-item="3-5"><div class="lab-step">When the alarm sounds, stop the timer, and count the number of flies in the open side B of the chamber.
</div></li><li data-sub-note-item="3-6"><div class="lab-step">Subtract that number from the total number of flies added to the choice chamber to calculate the number of flies in the covered side A.
</div></li><li data-sub-note-item="3-7"><div class="lab-step">Record these data in the table for time point 10.  <a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/15/Table_2_Animal_behavior.xlsx" style="display:block;margin:20px;" target="__blank">Click Here to download Table 2</a>
</div></li><li data-sub-note-item="3-8"><div class="lab-step">Carefully, return all of the flies back to their empty vial.
</div></li></ul></li><li data-note-item="4" data-parent-collapse="">Chemotaxis
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="4-1"><div class="lab-step">HYPOTHESES: In this exercise, the alternative hypothesis is that more flies will be found on the side of the chamber with the apple cider vinegar if the flies are attracted to the odor. Or, if the flies are repelled by the vinegar, then more of them will be found on the side of the chamber presenting the odorless water. The null hypothesis is that <em>Drosophila</em> will have no preference with regard to either stimulus and will move randomly in the chamber.  Use an individual disposable plastic pipette to dispense two drops of the apple cider vinegar onto one cotton ball for side A of the chamber. 
</div></li><li data-sub-note-item="4-2"><div class="lab-step">Use an individual disposable plastic pipette to dispense two drops of the distilled water onto a cotton ball for side B of the chamber. 
</div></li><li data-sub-note-item="4-3"><div class="lab-step">Fold two pieces of tape over themselves to create individual pieces of double-sided tape and use the tape to attach each cotton ball to the inside of the single bottle cap.
</div></li><li data-sub-note-item="4-4"><div class="lab-step">Screw the bottle caps with the cotton balls onto their corresponding sides of the chamber.
</div></li><li data-sub-note-item="4-5"><div class="lab-step">Transfer all of the flies into the chamber and set the timer to sound an alarm after 10 minutes. 
</div></li><li data-sub-note-item="4-6"><div class="lab-step">When the alarm sounds, stop the timer and record the number of flies in each side of the chamber. <a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/15/Table_3_Animal_behavior.xlsx" style="display:block;margin:20px;" target="__blank">Click Here to download Table 3</a>
</div></li><li data-sub-note-item="4-7"><div class="lab-step">At the end of the final experiment, funnel the flies into a morgue tube containing 70% ethanol. 
</div></li><li data-sub-note-item="4-8"><div class="lab-step">Dismantle the choice chambers for recycling.  NOTE: Since all of the chemicals used in these experiments are lab safe, the liquids can be disposed of down the sink, the chambers rinsed, and the solids can be thrown away in the trash. 
</div></li></ul></li><li data-note-item="5" data-parent-collapse="">Results
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="5-1"><div class="lab-step">Gather all of the data collected for the geotaxis, phototaxis, and chemotaxis experiments.
</div></li><li data-sub-note-item="5-2"><div class="lab-step">Plot these values as bar graphs for different conditions and different time points.
</div></li><li data-sub-note-item="5-3"><div class="lab-step">Use these data to draw inferences about the behavior of <em>drosophila melanogaster</em>. 
</div></li></ul></li></ol>

Animal Behavior: Studying Taxis Behavior of Drosophila - Procedure

Hayvan Davranışı

Making Choice Chambers
ExpandBefore beginning the experiments, use one of the Sharpies from the lab table to trace a line around the circumference of the ...

Extinction

<ol class="note-items"><li data-note-item="1" data-parent-collapse="">Diversity and Extinction during the Paleogene Epoch
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="1-1"><div class="lab-step">Begin this procedure by reading the extinction reading supplement that has been printed out for you. <br /><strong>NOTE:</strong> Alternatively, you may download the reading supplement at the link below.&nbsp; <a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/24/Lab_20_Reading Supplement.docx" style="display:block;margin:20px;" target="_blank">Click here to download the extinction reading supplement</a>
</div></li><li data-sub-note-item="1-2"><div class="lab-step">Using the information contained in the extinction reading supplements pertaining to the taxa of interest and the Chicxulub impact event, make predictions for each taxon listed in Table 1. Consider whether diversity in each taxon increased, decreased, or stayed the same immediately following the Cretaceous-Paleogene boundary and later on in the Paleogene epoch. <a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/24/Table_1_Extinction.xlsx" style="display:block;margin:20px;" target="_blank">Click Here to download Table 1</a>
</div></li><li data-sub-note-item="1-3"><div class="lab-step">Then, fill out the reasons for each of your predictions in the Contributing Factors column. HYPOTHESES: The experimental hypothesis is that many of the different taxa will show changes in diversity after the Cretaceous-Paleogene event, and again at the end of the Paleogene, with some increasing in diversity, while others decrease. The null hypothesis is that there will be no changes in diversity between taxa following the Cretaceous-Paleogene event, or at the end of the Paleogene.
</div></li><li data-sub-note-item="1-4"><div class="lab-step">Gather diversity data by going to the Paleobiology Database: <a href="http://www.paleobiodb.org" target="_blank">www.paleobiodb.org</a>.
</div></li><li data-sub-note-item="1-5"><div class="lab-step">In the center of the screen, click the yellow box labeled Download Data. Under the italicized heading, &#8220;What do you want to download?&#8221;, select Diversity over time on the left side and Comma-separated values on the right side.
</div></li><li data-sub-note-item="1-6"><div class="lab-step">Scroll down to the heading &#8220;Select by taxonomy&#8221;.
</div></li><li data-sub-note-item="1-7"><div class="lab-step">In the first box labeled 'Taxon or taxa to include', type in the name of the taxon that data is being gathered on.  NOTE: Ensure the spelling is correct.
</div></li><li data-sub-note-item="1-8"><div class="lab-step">Now, go to the dropdown menu right below that box labeled &#8220;Taxonomic resolution&#8221;, and select genera.
</div></li><li data-sub-note-item="1-9"><div class="lab-step">Under the next heading, Select by time, type Maastrichtian into the first box and Chattian in the box directly below. Make sure the dropdown menu labeled Time rule is set to major and the Temporal resolution is set to stage.
</div></li><li data-sub-note-item="1-10"><div class="lab-step">Select &#8220;Assume extant taxa range through to present&#8221;. Scroll back up to the middle of the page and click download. A save window will open.
</div></li><li data-sub-note-item="1-11"><div class="lab-step">Save the .csv file to a safe and accessible place and rename it to make it easy to identify.
</div></li><li data-sub-note-item="1-12"><div class="lab-step">Open the file and scroll down to the main dataset under Records.  NOTE: The data are arranged in reverse time order by geological stage. The second column, interval_name, gives the accepted name of the stage in question. The next two columns give the appropriate dates of the stage in millions of years before the present. The final column, number of occurrences, gives a total count of the genera extant during that geological stage as determined from occurrence of fossils.
</div></li><li data-sub-note-item="1-13"><div class="lab-step">To more easily work with this data, copy and paste each column into a new sheet. Be sure to label this sheet with the taxon in question, the data and time the data were obtained, and the data source.
</div></li><li data-sub-note-item="1-14"><div class="lab-step">Repeat this process for each of the taxa in Table 1 (steps 4 &#8211; 12). NOTE: Data from multiple taxa can be kept on the same sheet, so long as they are kept distinct and labeled appropriately.
</div></li><li data-sub-note-item="1-15"><div class="lab-step">To create line plots for each of the taxa showing the change in diversity over time, select the max_ma column and the number of occurrences column simultaneously.
</div></li><li data-sub-note-item="1-16"><div class="lab-step">In Excel, select Insert from the top toolbar and find the section labeled Charts. Select the bottom center icon, Insert Scatter Chart.
</div></li><li data-sub-note-item="1-17"><div class="lab-step">Then, select the Scatter with Straight Lines and Markers and a graph should appear. NOTE: Since the axis of this graph is in units of millions of years ago, the axis is in the reverse direction of time when put in numerical order.
</div></li><li data-sub-note-item="1-18"><div class="lab-step">To fix this, click on the green plus sign in the top-right corner of the graph and hover over Axes. This should reveal a small black arrow. Click the arrow to open up a small menu and select More Options.
</div></li><li data-sub-note-item="1-19"><div class="lab-step">This will open the Axis Options menu. Under Axis Options, click the box next to Values in reverse order. NOTE: It is also possible to change the axis scales from this menu, which can be used to eliminate the excess time that is not being analyzed in this lab. Keep any changes consistent between different graphs.
</div></li><li data-sub-note-item="1-20"><div class="lab-step">Double-click on the title at the top of the graph and change it to the taxon being represented.
</div></li><li data-sub-note-item="1-21"><div class="lab-step">Make a separate graph for each of the taxa in Table 1. Keep them organized and in one location. A separate sheet for graphs is recommended.
</div></li></ul></li><li data-note-item="2" data-parent-collapse="">Results
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="2-1"><div class="lab-step">For each graph, identify the location of the Cretaceous-Paleogene boundary and draw a vertical line through the graph at this point.
</div></li><li data-sub-note-item="2-2"><div class="lab-step">Using the information from the graphs, fill out Table 2. In some cases, it may be helpful to go back to the original dataset and compare actual values, particularly when they are small. <a href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/24/Table_2_Extinction.xlsx" style="display:block;margin:20px;" target="_blank">Click Here to download Table 2</a>
</div></li><li data-sub-note-item="2-3"><div class="lab-step">Compare these values to the predictions made in Table 1 and discuss if the original contributing factors are still likely candidates.
</div></li><li data-sub-note-item="2-4"><div class="lab-step">Using the dataset, calculate the percentage of total taxa that went extinct over the Cretaceous-Paleogene boundary using this equation.
</div></li><li data-sub-note-item="2-5"><div class="lab-step">There is an event in the middle of the Paleogene known as the Paleocene-Eocene Thermal Maximum about 55.5 million years ago. This represents a high point in temperature during the Paleogene epoch at approximately 8 &#176;C higher than today&#39;s average temperature. Does this point seem to have an effect on diversity for any of the taxa? If yes, then which ones?
</div></li></ul></li></ol>

Extinction: Diversity and Extinction during the Paleogene Epoch - Procedure

Diversity and Extinction during the Paleogene Epoch
ExpandBegin this procedure by reading the extinction reading supplement that has been printed out for ...

Artificial Selection

<ol class="note-items"><li data-note-item="1" data-parent-collapse="">Observing Artificial Selection in Plants 
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="1-1"><div class="lab-step">To begin the experiment, collect five two-week old grown plants from the generation one population that appear healthy. Note: Plants should appear green, not wilted, and not have damaged leaves. Experimental Hypothesis: The experimental hypothesis for this lab might be that the number of lead trichomes varies naturally, but the average number will increase over generations if only plants with the highest number of trichomes are interbred or decrease if those with the least are interbred. Null Hypothesis: The null hypothesis might be that the average number of trichomes will not change over subsequent generations after artificial selection.
</div></li><li data-sub-note-item="1-2"><div class="lab-step">Label each plant with a letter from A to E and with both partners&#8217; names.
</div></li><li data-sub-note-item="1-3"><div class="lab-step">Record any natural differences you see between your plant samples. Note: All of the plants are the same age, so any observed variation is due to expressed phenotype, not development.
</div></li><li data-sub-note-item="1-4"><div class="lab-step">Use a hand lens to count the number of trichomes found on the petiole of the lowest leaf, not including the round, first-grown cotyledons for each plant. Note: It can be helpful to shine a light onto the plant and to hold it against a dark background, such as a lab bench, during the trichome analysis. 
</div></li><li data-sub-note-item="1-5"><div class="lab-step">Both partners will conduct counts on each plant independently and compare answers. If the counts are different, enlist a third counter or take the average of the two results.
</div></li><li data-sub-note-item="1-6"><div class="lab-step">After this, determine the median number of trichomes for the entire class.  <a target="__blank" style="display:block;padding:20px;" href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/2/Lab_2_Table_A.xlsx">Click Here to download Table A</a>
</div></li><li data-sub-note-item="1-7"><div class="lab-step">Determine the top and bottom 10% of the plants from the class trichome count. These groups will make up the two artificially selected lines: high hairiness and low hairiness, respectively.
</div></li><li data-sub-note-item="1-8"><div class="lab-step">If more than 10% of the plants have no trichomes, select 10% of those plants randomly for the low hairiness plant line.
</div></li><li data-sub-note-item="1-9"><div class="lab-step">Separate the two groups of selected plants and label them clearly.
</div></li><li data-sub-note-item="1-10"><div class="lab-step">Move the plants to a well-lit area and keep them well watered until they develop flowers. Note: Flowers typically develop around 14 days.
</div></li><li data-sub-note-item="1-11"><div class="lab-step">When the flowers are fully developed, use a pollination wand or paintbrush to rub the stigma and anther of one plant&#8217;s flowers for a few seconds.
</div></li><li data-sub-note-item="1-12"><div class="lab-step">Using the same wand or brush, rub the inside of each flower of every other plant in the same selection line.
</div></li><li data-sub-note-item="1-13"><div class="lab-step">Using a different wand or brush, repeat steps 11 through 12 on the other line. Note: Take care not to cross the lines. Spread the pollen only among the appropriately selected plants.
</div></li><li data-sub-note-item="1-14"><div class="lab-step">Return the generation one plants to the growing areas. When the plants reach approximately 1 month old, they should produce mature seed pods.
</div></li><li data-sub-note-item="1-15"><div class="lab-step">Allow the plants to dry out once the seed pods turn yellow.
</div></li><li data-sub-note-item="1-16"><div class="lab-step">Break the seed pods open and collect the seeds.
</div></li><li data-sub-note-item="1-17"><div class="lab-step">Obtain new pots for the generation two seeds.
</div></li><li data-sub-note-item="1-18"><div class="lab-step">Fill the pots with moist potting soil about halfway and add a fertilizer pellet to each pot.
</div></li><li data-sub-note-item="1-19"><div class="lab-step">Fill the pots with more soil to fill just below the lip.
</div></li><li data-sub-note-item="1-20"><div class="lab-step">Make a shallow depression in the soil of each pot with a probe.
</div></li><li data-sub-note-item="1-21"><div class="lab-step">Touch a clean toothpick to a gluestick and use the toothpick to transplant the seeds into the soil one by one.
</div></li><li data-sub-note-item="1-22"><div class="lab-step">Cover the seeds with a thin layer of soil.
</div></li><li data-sub-note-item="1-23"><div class="lab-step">Label the pots with their hairiness line and place them in the designated growing area.
</div></li><li data-sub-note-item="1-24"><div class="lab-step">Use a plastic dropper to water the plants as needed to ensure they do not dry out.
</div></li><li data-sub-note-item="1-25"><div class="lab-step">When the plants are two weeks old, collect five plants from each line and label them A to E.
</div></li><li data-sub-note-item="1-26"><div class="lab-step">Then, count the trichomes on these plants as previously described (steps 4- 5).
<a target="__blank" style="display:block;padding:20px;" href="https://www-jove-com.remotexs.ntu.edu.sg/CDNSource/lm/labs/2/Lab_2_Table_B.xlsx">Click Here to download Table B</a>
</div></li></ul></li><li data-note-item="2" data-parent-collapse="">Data Analysis
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="2-1"><div class="lab-step">Create a frequency graph based on the generation one class data with the trichome count on the x axis and the number of plants on the y axis. Label the mean. 
</div></li><li data-sub-note-item="2-2"><div class="lab-step">Then, create frequency graphs for both of the selected hairiness lines.
</div></li><li data-sub-note-item="2-3"><div class="lab-step">Compare the frequency graphs for generation one and both hairiness lines.
</div></li><li data-sub-note-item="2-4"><div class="lab-step">Take note of phenotypic shifts observed in the selected hairiness lines.
</div></li></ul></li></ol>

Artificial Selection: Visualization in Plants and Data Analysis - Procedure

Yapay Seçilim

Observing Artificial Selection in Plants 
ExpandTo begin the experiment, collect five two-week old grown plants from the generation one population that ...