<h3 id="successevolutionsuccess"><Success>Evolution</Success></h3> <h3 id="successpart---3success"><Success>Part - 3</Success></h3> <div style='text-align: center; justify-content: center;width:100%;'> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-08-chapter-03-genetics-and-evolution-evolution-l-3_3-bxn5mmlhdus-019-0080.4.jpg"> <img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-08-chapter-03-genetics-and-evolution-evolution-l-3_3-bxn5mmlhdus-01.jpg"></p> </div>

<h3 id="successevolutionsuccess-1"><Success>Evolution</Success></h3> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <ul> <li>Evolutionary Theories</li> <li>Lamarckism</li> <li>Darwinism</li> <li>Hugo de Vries</li> <li>Theories for evolution of life Biogenesis (living organisms originate only from other living organisms)</li> </ul> <!--Biogenesis proceded by Chemical Evolution--> <!--Theories for Origin of Life--> <!--Origin of Life--> <!--Universe (Big Bang Theory)--> <!--Earth (Nebular Hypothesis)--> <!--First life forms (Theory of Chemical Evolution)--> <!--Oparin of Russia & Haldane of England--> <!--Environmental Evidence--> <!--Stanley Miller & Harold Urey--> <!--Palaentology--> <!--Morphology--> <!--Anatomy--> <!--Evidences--> <!--Biochemistry--> <!--Embryology--> <!--Connecting links--> <!--Missing Links--> <!--Vestigial Organs--> <!--Direct Observation--> <!--Anthropogenic Evolution--> <!--### TYPES--> <!--Convergent Evolution--> <!--Parallel Evolution --> <!--Analogy--> <!--Divergent Evolution--> <!--Adaptive Radiation--> <!--Homology--> <!--### Evolution Theories--> <!--Lamarckism--> <!--Darwinism--> <!--Hugo de Vries Mutation--> </div> <!--<div style='float: right; width:0%;'>--> <!----> <!--</div>-->

<div> <h3 id="successevolutionsuccess-2"><Success>Evolution</Success></h3> </div> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <ul> <li>Origin of life</li> <li>Universe (Big Bang theory)</li> <li>Earth (Nebular hypothesis First life form (theory of chemical evolution)</li> <li>Oparin and Haldane theory of chemical evolution</li> <li>Miller and Urey experiment</li> <li>Types of evolution</li> <li>Divergent evolution (Adaptive radiation) $\rarr$ Homology</li> <li>Convergent evolution $\rarr$ $\rarr$ Analogy</li> <li>Parallel evolution $\rarr$ Analogy</li> </ul> </div>

<div> <h3 id="successspeciationsuccess"><Success>Speciation</Success></h3> </div> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <p><strong>Species</strong> A of group of similar organisms or members of a population which can potentially in nature</p> <p>Species 2</p> <p>↑ Accumulation of variation</p> <p>Species 1</p> </div> <!--<div style='float: right; width:50%;'>--> <!----> <!----> </div>

<h3 id="successspeciation-due-to-geographical-barriersuccess"><Success>Speciation due to geographical barrier</Success></h3> <div style='float: right; width:100%;font-size:30px;'> <p>Reproductive Isolation $\rarr$ Geographical barrier</p> <img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/735b8e43-c5fa-4ce1-ed08-0a3d6b42dc00/public" width="60%"> </div>

<h3 id="successhardy-weinberg-equilibriumsuccess"><Success>Hardy-Weinberg equilibrium</Success></h3> <div style='float: left; width:50%;font-size:30px;text-align:left;'> <ul> <li>G.H. Hardy and W. Weinberg</li> </ul> <p><strong>Genetic equilibrium</strong> The condition where a gene pool remains constant in frequency across generations</p> <p><strong>Gene pool</strong> Sum total of all the genes and their alleles in population</p> <p>I $\rarr$ I^A, I^B, i</p> <!--- I--> <!-- - I^AI^B--> <!-- - I^Ai--> <!-- - I^Bi--> </div> <div style='float: right; width:0%;'> <img src="/subject-images/iitpal/image/biology-class-12-unit-08-chapter-03-genetics-and-evolution-evolution-l-3_3-bxn5mmlhdus-06.jpg" width="50%"> <!---->

<h3 id="successhardy-weinberg-equilibriumsuccess-1"><Success>Hardy-Weinberg equilibrium</Success></h3> <div style='float: left; width:100%;font-size:20px;text-align:left;'> <ul> <li>Allele frequencies within a population remain stable across successive generations</li> </ul> <p><strong>Mathematical Expression</strong> A, a</p> <p>$f$(A) → P</p> <p>$f$(a) → P</p> <p>Sum Total of all = 1</p> <p>$ p^2+q^2+2 p q=1 \ $</p> <p>$ (p+q)^2=1 $</p> <p>$ A A \rightarrow p^2 $</p> <p>$ a a \rightarrow q^2 $</p> <p>$ \text { Aa } \rightarrow 2 p q $</p> </div> <div style='float: right; width:0%;font-size:30px;text-align:left;'> <!----> <!----> </div>

<h3 id="successhardy-weinberg-equilibriumsuccess-2"><Success>Hardy-Weinberg equilibrium</Success></h3> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <ul> <li> <p>Ideal condition where there is no evolutionary change</p> </li> <li> <p>Frequency of occurence of allele is from the expected frequency, we can find out the extent of evolution</p> </li> </ul> </div> <!--<div style='float: right; width:50%;'>--> <!----> <!---->

<h4 id="success-factors-affecting-hardy-weinberg-equilibriumsuccess"><Success> Factors affecting Hardy-Weinberg equilibrium</Success></h4> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <ul> <li> <p>Factors</p> </li> <li> <p>Gene Flow/migration</p> </li> <li> <p>Genetic Drift</p> </li> <li> <p>Genetic Recombination</p> </li> <li> <p>Mutation</p> </li> <li> <p>Natural Selection</p> </li> </ul> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-08-chapter-03-genetics-and-evolution-evolution-l-3_3-bxn5mmlhdus-119-2068.8.jpg"></p> </div>

<h3 id="successmodes-of-natural-selectionsuccess"><Success>Modes of natural selection</Success></h3> <div style='float: left; width:100%;'> <img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/406356a2-3266-45b7-f66a-9654fe1a3b00/public" width="30%"> </div> <img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/8cf82368-7ba1-43fa-af5a-804799f39e00/public" width="30%"> </div>

<h3 id="successmodes-of-natural-selectionsuccess-1"><Success>Modes of natural selection</Success></h3> <!--<div style='float: left; width:100%;font-size:30px;text-align:left;'>--> <!--| ERA | Time Period | Event |--> <!--| -------- | -------- | --------|--> <!--| Proterozoic | 2 billion years ago | First Cellular form (molecular aggregates Cell and Unicellular - Multicellular) |--> <!--| Palaeozoic | 500 million years ago | Invertebrates |--> <!--| Palaeozoic | 350 million years ago | Jawless Fishes (Agnatha) |--> <!--| | 320 million years ago | Sea Weeds & Aquatic Plants |--> <!--| | | Fish with stout & strong fins (amphibious) LOBEFINS |--> <!--| | | Coelacanth found in 1938 in South Africa |--> <!--| | 250 million years ago | First Amphibians (frogs, salamanders) |--> <!--</div>--> <div style='float: right; width:100%;'> <img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/ad66c33e-f0ab-4628-fb0e-d459c3e0ef00/public" width="60%"> </div> <!--<div style='float: right; width:50%;'>--> <!----> <!---->

<div> <h3 id="successbrief-account-of-evolutionsuccess"><Success>Brief account of evolution</Success></h3> </div> <!--<div style='float: left; width:100%;font-size:30px;text-align:left;'>--> <!--## MESOZOIC--> <!--**200 Million years ago**--> <!--**Reptiles**--> <!--- Crocodile--> <!--- Tortoise--> <!--- Turtles--> <!--- Water (fish like reptiles)--> <!--- Land (Dinosaurs)--> <!--**65 Million Years Ago**--> <!--- Sudden disappearance of Dinosaurs--> <!--- Giant ferns fall down -> Coal Deposits--> <!--## COENOZOIC--> <!--**63 Million years ago**--> <!--**Birds**--> <!--- Mammals (Shrewlike, viviparous, good sense)--> <!--- Ancestral forms - horse, Hippo--> <!--**1-0 million years ago**--> <!--Continental Drift - SA joined N. America, Australia separated--> <!--</div>--> <div style='float: right; width:100%;'> <img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/a69ae380-762d-4a5d-de56-da3f9d34a800/public" width="60%"> </div> <!--<div style='float: right; width:50%;'>--> <!----> <!---->

<div> <h3 id="successbrief-account-of-evolutionsuccess-1"><Success>Brief account of evolution</Success></h3> </div> <!--<div style='float: left; width:100%;font-size:30px;text-align:left;'>'>--> <!--## Origin and Evolution of Man--> <!--**15 mya**--> <!--Primates--> <!--- Dryopithecus (hairy, ape like)--> <!--- Ramapithecus (more man like)--> <!--- fossils of man like bones -> Ethiopia and Tanzania--> <!--**3-4 mya**--> <!--- Man like primates - Eastern Africa--> <!--- Hominid Features - 4 ft. tall walked upright--> <!--**2 mya**--> <!--- Australopithecine (fruit eating, hunted with stone weapon)--> <!--- Homo habits (650 - 800 CC)--> <!--**1.5 mya**--> <!--- Homo erectus (900 CC) - ate meats (fossil discovered in Java)--> <!--**1L to 40k years back**--> <!--- Neanderthal man (1400 CC) - found in E & C. Asia--> <!--**75k to 10k years back**--> <!--- Homo Sapiens --> <!--**18k years ago**--> <!--- Arose in Africa & spread across continents pre historical caste art--> <!--**10k years ago**--> <!--- Agriculture -> Settlement--> <!--</div>--> <div style='float: right; width:100%;'> <img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/aff4c877-d088-46d4-0210-337fbae12200/public" width="60%"> </div> <!--<div style='float: right; width:50%;'>--> <!----> <!---->

<div> <h3 id="successorigin-and-evolution-of-mansuccess"><Success>Origin and evolution of man</Success></h3> </div> <!--<div style='float: left; width:100%;font-size:30px;text-align:left;'>--> <!--**15 mya**--> <!--Primates--> <!--- Dryopithecus (hairy, ape like)--> <!--- Ramapithecus (more man like)--> <!--- fossils of man like bones -> Ethiopia and Tanzania--> <!--**3-4 mya**--> <!--- Man like primates - Eastern Africa--> <!--- Hominid Features - 4 ft. tall walked upright--> <!--**2 mya**--> <!--- Australopithecine (fruit eating, hunted with stone weapon)--> <!--- Homo habits (650 - 800 CC)--> <!--**1.5 mya**--> <!--- Homo erectus (900 CC) - ate meats (fossil discovered in Java)--> <!--**1L to 40k years back**--> <!--- Neanderthal man (1400 CC) - found in E & C. Asia--> <!--**75k to 10k years back**--> <!--- Homo Sapiens --> <!--**18k years ago**--> <!--- Arose in Africa & spread across continents pre historical caste art--> <!--**10k years ago**--> <!--- Agriculture -> Settlement--> <!--</div>--> <div style='float: right; width:100%;'> <img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/eeb33926-14b2-4b90-4287-c137311ae600/public" width="40%"> </div>

<div> <h3 id="successlets-summarizesuccess"><Success>Let’s summarize</Success></h3> </div> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <p><strong>In today’s session, we learnt about the</strong></p> <ul> <li> <p>Concept of Species and Speciation</p> </li> <li> <p>Hardy Weinberg Equilibrium and 5 factors which affect it</p> </li> <li> <p>A brief account of evolution</p> </li> <li> <p>Origin and Evolution of man</p> </li> </ul> </div> <!--<div style='float: right; width:50%;'>--> <!----> <!---->

<div> <h3 id="successlets-discusssuccess"><Success>Let’s discuss</Success></h3> </div> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <p><strong>Questions which were given in the last session-</strong></p> <p><strong>Question</strong> Explain antibiotic resistance observed in bacteria in light of darwinian selection theory</p> <p><strong>Question</strong> Find out from newspapers and popular science articles about any new fossil discoveries or controversies about evolution</p> <p><strong>Question</strong> Attempt giving a clear definition of the term species</p> <p><strong>Question</strong> Describe one example of adaptive radiation</p> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-08-chapter-03-genetics-and-evolution-evolution-l-3_3-bxn5mmlhdus-188-3063.6.jpg"></p> <p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-08-chapter-03-genetics-and-evolution-evolution-l-3_3-bxn5mmlhdus-15a.jpg"></p> <p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-08-chapter-03-genetics-and-evolution-evolution-l-3_3-bxn5mmlhdus-15aa.jpg"></p> <p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-08-chapter-03-genetics-and-evolution-evolution-l-3_3-bxn5mmlhdus-15aaa.jpg"></p> <p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-08-chapter-03-genetics-and-evolution-evolution-l-3_3-bxn5mmlhdus-15aaaa.jpg"></p> <p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-08-chapter-03-genetics-and-evolution-evolution-l-3_3-bxn5mmlhdus-15aaaaa.jpg"></p> </div>

<div> <h3 id="successlets-discusssuccess-1"><Success>Let’s discuss</Success></h3> </div> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <p>The remaining questions of your NCERT</p> <p><strong>Exercise</strong></p> <p><strong>Question</strong> Attempt giving a clear definition of the term species</p> <p><strong>Answer</strong> A ‘species’ can be described as a potentially interbreeding group of individuals that are reproductively isolated from other populations</p> </div>

<div> <h3 id="successlets-discusssuccess-2"><Success>Let’s discuss</Success></h3> </div> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <p><strong>Question</strong> Try to trace the various components of human evolution.</p> <p><strong>Question</strong> Can we call human evolution as adaptive radiation?</p> <p><strong>Answer</strong> Human population is one single species evolution which occured as a result of various factors like mutation, genetic drift, migration, genetic recombination etc led to formation of races</p> </div>

<div> <h3 id="successlets-discusssuccess-3"><Success>Let’s discuss</Success></h3> </div> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <p><strong>Question</strong> Trace the evolutionary stage of horse</p> <p><strong>Answer.</strong> Eohippus (North America) - 60 mya, size of about a fox, had 4 toes on each fore foot and 3 on each hind foot</p> <p>Mesohippus (40 mya), size of goat, three toes on each foot</p> <p>Merychippus (35 mya), size of an ass, could run on one toe only</p> <p>Pliohippus (20 mya) → Equus (Modern horse - 5 lakh years ago)</p> <p>One toe on each fore foot and hind foot</p> </div>

<div> <h3 id="successlets-evaluatesuccess"><Success>Let’s evaluate</Success></h3> </div> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <p><strong>Question 1</strong> Homologous organs indicate</p> <p>a. Convergent Evolution</p> <p>b. Parallel Evolution</p> <p>c. Common Descendent</p> <p>d. Natural Selection</p> </div>

<div> <h3 id="successlets-evaluatesuccess-1"><Success>Let’s evaluate</Success></h3> </div> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <p><strong>Question 2</strong> One of the important consequences of geographical isolation is</p> <p>a. Random creation of new species</p> <p>b. No change in the isolated form</p> <p>c. Preventing speciation</p> <p>d. Speciation through reproductive isolation</p> </div>

<div> <h3 id="successlets-evaluatesuccess-2"><Success>Let’s evaluate</Success></h3> </div> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <p><strong>Question 3</strong> What is meant by the term Darwin fitness?</p> <p>a. The ability to survive and reproduce</p> <p>b. High aggressiveness</p> <p>c. Healthy appearance</p> <p>d. Physical strength</p> </div> <!--<div style='float: right; width:50%;'>--> <!----> <!---->

<div> <h3 id="successlets-evaluatesuccess-3"><Success>Let’s evaluate</Success></h3> </div> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <p><strong>Question 4</strong> What is common to Whale, seal and shark?</p> <p>a. Homeothermy</p> <p>b. Seasonal migration</p> <p>c. Thick subcutaneous fat</p> <p>d. Convergent evolution</p> </div>

<div> <h3 id="successlets-evaluatesuccess-4"><Success>Let’s evaluate</Success></h3> </div> <div style='float: left; width:100%;font-size:30px;text-align:left;'> <p><strong>Question 5</strong> Chemical reactions could have converted simple organic compounds into ________ for the origin of life</p> <p>a. Micromolecules</p> <p>b. Nitrogen, oxygen and other gases</p> <p>c. Cells</p> <p>d. Macromolecules</p> </div> <div style='float: right; width:0%;'> <p><img alt="image" src="https://temp-public-img-folder.s3.ap-south-1.amazonaws.com/sathee.prutor.images/subject-images/iitpal/image/biology-class-12-unit-08-chapter-03-genetics-and-evolution-evolution-l-3_3-bxn5mmlhdus-17.jpg">

<div> <h3 id="successthank-yousuccess"><Success>Thank you</Success></h3> </div> <div style='float: left; width:100%;font-size:30px;text-align:left;'> </div>