### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Evolution </primary> <hr> <main> <div style='text-align: center; justify-content: center;width:100%;'> </div> <div style='float: right; width:0%;'>   </div> </main> <hr> <footer style = "font-size: 18px"> $\rightarrow$ $\rightarrow$ <span style = "color:blue"> Evolution </span> $\rightarrow$ Evolution $\rightarrow$ Evolution </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Evolution </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - Evolutionary Theories - Lamarckism - Darwinism - Hugo de Vries - Theories for evolution of life Biogenesis (living organisms originate only from other living organisms) </div> <!--<div style='float: right; width:0%;'>--> <!----> <!--</div>--> </main> <hr> <footer style = "font-size: 18px"> $\rightarrow$ Evolution $\rightarrow$ <span style = "color:blue"> Evolution </span> $\rightarrow$ Evolution $\rightarrow$ Speciation </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Evolution </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - Origin of life - Universe (Big Bang theory) - Earth (Nebular hypothesis First life form (theory of chemical evolution) - Oparin and Haldane theory of chemical evolution - Miller and Urey experiment - Types of evolution - Divergent evolution (Adaptive radiation) $\rightarrow$ Homology - Convergent evolution $\rightarrow$ $\rightarrow$ Analogy - Parallel evolution $\rightarrow$ Analogy </div> </main> <hr> <footer style = "font-size: 18px">Evolution $\rightarrow$ Evolution $\rightarrow$ <span style = "color:blue"> Evolution </span> $\rightarrow$ Speciation $\rightarrow$ Speciation due to geographical barrier </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Speciation </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - **Species** A of group of similar organisms or members of a population which can - potentially in nature - Species 2 ↑ Accumulation of variation - Species 1 </div> <!--<div style='float: right; width:50%;'>--> <!----> <!----> </div> </main> <hr> <footer style = "font-size: 18px">Evolution $\rightarrow$ Evolution $\rightarrow$ <span style = "color:blue"> Speciation </span> $\rightarrow$ Speciation due to geographical barrier $\rightarrow$ Hardy-Weinberg equilibrium </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Speciation due to geographical barrier </primary> <hr> <main> <div style='float: right; width:100%;font-size:30px;'> - Reproductive Isolation $\rightarrow$ Geographical barrier <img src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/735b8e43-c5fa-4ce1-ed08-0a3d6b42dc00/public" width="60%"> </div> </main> <hr> <footer style = "font-size: 18px">Evolution $\rightarrow$ Speciation $\rightarrow$ <span style = "color:blue"> Speciation due to geographical barrier </span> $\rightarrow$ Hardy-Weinberg equilibrium $\rightarrow$ Hardy-Weinberg equilibrium </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Hardy-Weinberg equilibrium </primary> <hr> <main> <div style='float: left; width:50%;font-size:30px;text-align:left;'> - G.H. Hardy and W. Weinberg - **Genetic equilibrium** The condition where a gene pool remains constant in frequency across generations - **Gene pool** Sum total of all the genes and their alleles in population - I $\rightarrow$ I^A, I^B, i <!--- 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%"> <!----> </main> <hr> <footer style = "font-size: 18px">Speciation $\rightarrow$ Speciation due to geographical barrier $\rightarrow$ <span style = "color:blue"> Hardy-Weinberg equilibrium </span> $\rightarrow$ Hardy-Weinberg equilibrium $\rightarrow$ Hardy-Weinberg equilibrium </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Hardy-Weinberg equilibrium </primary> <hr> <main> <div style='float: left; width:100%;font-size:20px;text-align:left;'> - Allele frequencies within a population remain stable across successive generations - **Mathematical Expression** A, a - $f$(A) → P - $f$(a) → P - Sum Total of all = 1 - $ p^2+q^2+2 p q=1 \\ $ - $ (p+q)^2=1 $ - $ A A \rightarrow p^2 $ - $ a a \rightarrow q^2 $ - $ \text { Aa } \rightarrow 2 p q $ </div> <div style='float: right; width:0%;font-size:30px;text-align:left;'> <!----> <!----> </div> </main> <hr> <footer style = "font-size: 18px">Speciation due to geographical barrier $\rightarrow$ Hardy-Weinberg equilibrium $\rightarrow$ <span style = "color:blue"> Hardy-Weinberg equilibrium </span> $\rightarrow$ Hardy-Weinberg equilibrium $\rightarrow$ Factors affecting Hardy-Weinberg equilibrium </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Hardy-Weinberg equilibrium </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - Ideal condition where there is no evolutionary change - Frequency of occurence of allele is from the expected frequency, we can find out the extent of evolution </div> <!--<div style='float: right; width:50%;'>--> <!----> <!----> </main> <hr> <footer style = "font-size: 18px">Hardy-Weinberg equilibrium $\rightarrow$ Hardy-Weinberg equilibrium $\rightarrow$ <span style = "color:blue"> Hardy-Weinberg equilibrium </span> $\rightarrow$ Factors affecting Hardy-Weinberg equilibrium $\rightarrow$ Modes of natural selection </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Factors affecting Hardy-Weinberg equilibrium </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - Factors - Gene Flow/migration - Genetic Drift - Genetic Recombination - Mutation - Natural Selection </div> <div style='float: right; width:0%;'>  </div> </main> <hr> <footer style = "font-size: 18px">Hardy-Weinberg equilibrium $\rightarrow$ Hardy-Weinberg equilibrium $\rightarrow$ <span style = "color:blue"> Factors affecting Hardy-Weinberg equilibrium </span> $\rightarrow$ Modes of natural selection $\rightarrow$ Modes of natural selection </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Modes of natural selection </primary> <hr> <main> <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> </main> <hr> <footer style = "font-size: 18px">Hardy-Weinberg equilibrium $\rightarrow$ Factors affecting Hardy-Weinberg equilibrium $\rightarrow$ <span style = "color:blue"> Modes of natural selection </span> $\rightarrow$ Modes of natural selection $\rightarrow$ Brief account of evolution </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Modes of natural selection </primary> <hr> <main> <!--<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%;'>--> <!----> <!----> </main> <hr> <footer style = "font-size: 18px">Factors affecting Hardy-Weinberg equilibrium $\rightarrow$ Modes of natural selection $\rightarrow$ <span style = "color:blue"> Modes of natural selection </span> $\rightarrow$ Brief account of evolution $\rightarrow$ Brief account of evolution </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Brief account of evolution </primary> <hr> <main> <!--<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%;'>--> <!----> <!----> </main> <hr> <footer style = "font-size: 18px">Modes of natural selection $\rightarrow$ Modes of natural selection $\rightarrow$ <span style = "color:blue"> Brief account of evolution </span> $\rightarrow$ Brief account of evolution $\rightarrow$ Origin and evolution of man </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Brief account of evolution </primary> <hr> <main> <!--<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%;'>--> <!----> <!----> </main> <hr> <footer style = "font-size: 18px">Modes of natural selection $\rightarrow$ Brief account of evolution $\rightarrow$ <span style = "color:blue"> Brief account of evolution </span> $\rightarrow$ Origin and evolution of man $\rightarrow$ Let's summarize </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Origin and evolution of man </primary> <hr> <main> <!--<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> </main> <hr> <footer style = "font-size: 18px">Brief account of evolution $\rightarrow$ Brief account of evolution $\rightarrow$ <span style = "color:blue"> Origin and evolution of man </span> $\rightarrow$ Let's summarize $\rightarrow$ Let's discuss </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Let's summarize </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - **In today's session, we learnt about the** - Concept of Species and Speciation - Hardy Weinberg Equilibrium and 5 factors which affect it - A brief account of evolution - Origin and Evolution of man </div> <!--<div style='float: right; width:50%;'>--> <!----> <!----> </main> <hr> <footer style = "font-size: 18px">Brief account of evolution $\rightarrow$ Origin and evolution of man $\rightarrow$ <span style = "color:blue"> Let's summarize </span> $\rightarrow$ Let's discuss $\rightarrow$ Let's discuss </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Let's discuss </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - **Questions which were given in the last session-** - **Question** Explain antibiotic resistance observed in bacteria in light of darwinian selection theory - **Question** Find out from newspapers and popular science articles about any new fossil discoveries or controversies about evolution - **Question** Attempt giving a clear definition of the term species - **Question** Describe one example of adaptive radiation </div> <div style='float: right; width:0%;'>       </div> </main> <hr> <footer style = "font-size: 18px">Origin and evolution of man $\rightarrow$ Let's summarize $\rightarrow$ <span style = "color:blue"> Let's discuss </span> $\rightarrow$ Let's discuss $\rightarrow$ Let's discuss </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Let's discuss </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - The remaining questions of your NCERT - **Exercise** - **Question** Attempt giving a clear definition of the term species - **Answer** A 'species' can be described as a potentially interbreeding group of individuals that are reproductively isolated from other populations </div> </main> <hr> <footer style = "font-size: 18px">Let's summarize $\rightarrow$ Let's discuss $\rightarrow$ <span style = "color:blue"> Let's discuss </span> $\rightarrow$ Let's discuss $\rightarrow$ Let's discuss </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Let's discuss </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - **Question** Try to trace the various components of human evolution. - **Question** Can we call human evolution as adaptive radiation? - **Answer** 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 </div> </main> <hr> <footer style = "font-size: 18px">Let's discuss $\rightarrow$ Let's discuss $\rightarrow$ <span style = "color:blue"> Let's discuss </span> $\rightarrow$ Let's discuss $\rightarrow$ Let's evaluate </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Let's discuss </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - **Question** Trace the evolutionary stage of horse - **Answer.** Eohippus (North America) - 60 mya, size of about a fox, had 4 toes on each fore foot and 3 on each hind foot - Mesohippus (40 mya), size of goat, three toes on each foot - Merychippus (35 mya), size of an ass, could run on one toe only - Pliohippus (20 mya) → Equus (Modern horse - 5 lakh years ago) - One toe on each fore foot and hind foot </div> </main> <hr> <footer style = "font-size: 18px">Let's discuss $\rightarrow$ Let's discuss $\rightarrow$ <span style = "color:blue"> Let's discuss </span> $\rightarrow$ Let's evaluate $\rightarrow$ Let's evaluate </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Let's evaluate </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - **Question 1** Homologous organs indicate - a. Convergent Evolution - b. Parallel Evolution - c. Common Descendent - d. Natural Selection </div> </main> <hr> <footer style = "font-size: 18px">Let's discuss $\rightarrow$ Let's discuss $\rightarrow$ <span style = "color:blue"> Let's evaluate </span> $\rightarrow$ Let's evaluate $\rightarrow$ Let's evaluate </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Let's evaluate </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - **Question 2** One of the important consequences of geographical isolation is - a. Random creation of new species - b. No change in the isolated form - c. Preventing speciation - d. Speciation through reproductive isolation </div> </main> <hr> <footer style = "font-size: 18px">Let's discuss $\rightarrow$ Let's evaluate $\rightarrow$ <span style = "color:blue"> Let's evaluate </span> $\rightarrow$ Let's evaluate $\rightarrow$ Let's evaluate </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Let's evaluate </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - **Question 3** What is meant by the term Darwin fitness? - a. The ability to survive and reproduce - b. High aggressiveness - c. Healthy appearance - d. Physical strength </div> <!--<div style='float: right; width:50%;'>--> <!----> <!----> </main> <hr> <footer style = "font-size: 18px">Let's evaluate $\rightarrow$ Let's evaluate $\rightarrow$ <span style = "color:blue"> Let's evaluate </span> $\rightarrow$ Let's evaluate $\rightarrow$ Let's evaluate </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Let's evaluate </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - **Question 4** What is common to Whale, seal and shark? - a. Homeothermy - b. Seasonal migration - c. Thick subcutaneous fat - d. Convergent evolution </div> </main> <hr> <footer style = "font-size: 18px">Let's evaluate $\rightarrow$ Let's evaluate $\rightarrow$ <span style = "color:blue"> Let's evaluate </span> $\rightarrow$ Let's evaluate $\rightarrow$ Thank you </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Let's evaluate </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> - **Question 5** Chemical reactions could have converted simple organic compounds into ________ for the origin of life - a. Micromolecules - b. Nitrogen, oxygen and other gases - c. Cells - d. Macromolecules </div> <div style='float: right; width:0%;'>  </main> <hr> <footer style = "font-size: 18px">Let's evaluate $\rightarrow$ Let's evaluate $\rightarrow$ <span style = "color:blue"> Let's evaluate </span> $\rightarrow$ Thank you $\rightarrow$ </footer>

### <Success style="font-size:25px"> Genetics And Evolution Evolution L-3 </Success> ### <primary style="font-size:24px"> Thank you </primary> <hr> <main> <div style='float: left; width:100%;font-size:30px;text-align:left;'> </div> </main> <hr> <footer style = "font-size: 18px">Let's evaluate $\rightarrow$ Let's evaluate $\rightarrow$ <span style = "color:blue"> Thank you </span> $\rightarrow$ $\rightarrow$ </footer>