What Are Homologous Structures? Give an Example. is It Necessary that Homologous Structures Always Have a Common Ancestor? Justify Your Answer. - Science

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Short Note

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

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Solution

Homologous organs:
These are organs that are similar in origin but perform different functions. For example, the forelimbs of humans and the wings of birds perform different functions, but their skeletal structures are similar.
Yes, homology indicates common ancestry. Homologous organs follow the same basic plan of the organisation during their development but in the adult condition, these organs are modified to perform different functions as an adaptation to different environments. 

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2019-2020 (February) Delhi(Set 3)

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