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Question
Explain with an example for the given, how the following provides evidence in favor of evolution in organisms :
Homologous organs
Solution
Homologous organs:- Organs which have the same basic structure but different functions are called homologous organs.
Example:- The forelimbs of a man, lizard, frog, bird, and bat have the same basic design of bones, but they perform different functions. The forelimbs of a man are used for grasping, the forelimbs of a lizard are used for running, the forelimbs of a frog are used to prop up the front ends of the body when at rest and the forelimbs of a bird and bat are modified for flying. Hence, all these organisms use their forelimbs for performing different functions, but the forelimbs have originated from the same structural pattern.
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RELATED QUESTIONS
Explain with an example for the given, how the following provides evidence in favor of evolution in organisms :
Fossils
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There are five animals A, B, C, D and E. The animal A uses its modified forelimbs for flying. The animal B uses its forelimbs for running whereas the animal C uses its forelimbs for grasping. The animal D can live on land as well as in water and uses its forelimbs to prop up the front end of its body when at rest. The animal E which respires by using spiracles and tracheae uses wings for flying but its wings are analogous to the modified forelimbs of animal A.
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| (a) | (b) | (c) |
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