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Evolution

Short Answer Type

71. Describe De Vries Mutation theory.

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72. What is the main difference between Darwin's theory of natural selection and De Vries mutation theory ?

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73. What is competition in nature ? How does it affect the plant and animal life ? Mention some examples.

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Long Answer Type

74. Where did Darwin err in his theory of the “Origin of Species” through natural selection ?

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Short Answer Type

75. List three mechanisms by which variant genotypes can be produced in nature.

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76. Why is the frequency of sickle cell anaemia more in the malaria prone areas ?

In heterozygous individuals sickle-shaped RBC effectively kill the parasite. Thus these individuals become immune to malaria. Normal individuals are eliminated due to malaria, thus increasing the frequency of heterozygous individuals.

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Long Answer Type

77. What is industrial melanism ?

Explain how natural selection has worked on population of peppered moth in industrial area of England.

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Short Answer Type

78. What observations is natural selection based on ?

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79. How is artificial selection different from natural selection ?

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80. Polyploidy can also lead to the formation of a new species very rapidly. Explain.

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