Explain with the help of an example each how the following provide evidences in favour of education ( a) homologous organ ( b ) analogous organ (c ) fossil
Answers
b) Different kind of structure but used for same purposes. EX: Wings of bat and a bird.
c) Fossils are the prints of dead and decayed matter.
EX: Fossil of a dinosaur.
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a) 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.
(b) Analogous organs: Organs which have different basic structure but similar appearance and perform similar functions are called analogous organs.
Example: The wings of an insect and a bird have different structures, but they perform the same function of flying. Because the wings of insects and birds have different structures but perform similar functions, they are analogous organs.
(c) Fossils: The remains of dead animals or plants which lived in the remote past are known as fossils. The fossils provide evidence for evolution. For example, a fossil bird called Archaeopteryx looks like a bird, but it has many other features which are found in reptiles. It has feathered wings like those of birds but teeth and tail like those of reptiles. Therefore, Archaeopteryx is a connecting link between the reptiles and birds and hence suggests that birds have evolved from reptiles
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hope this helps :)