Q20 of 30 Page 1

What are homologous structures? Give an example. Is it necessary that homologous structures always have a common ancestor. Justify your answer.

Homologous structures are organs that have common origin/ same ancestors but perform different functions. For example, a dolphin's flipper, a bird's wing, a cat's leg, and a human arm are considered homologous structures.

Yes, it is necessary that they should have a common ancestor, otherwise there won’t be any similarity in the basic structure and body plan of the organisms.


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