Observe the illustration and answer the questions. What inferences regarding evolution can be drawn from the anatomy of these organs ?

The organisms have evolved, and their morphological characters have been modified due to their adaptation to the environment. The forelimbs of these organisms have the same structures but perform different functions. Anatomical resemblances justify the inferences that all these organisms evolved from a common ancestor.

Observe the diagrams and answer the questions based on them. To which animals do organs I and II belong?

Homologous organs are those organs that have the same origin but perform different functions. They have developed by divergent evolution. Example: Forelimb of humans and wing of bird have same basic structure but perform a different function. The organs I belongs to animal bat and organ II belongs to animal whale.

Observe the illustration and answer the questions. Why do the forelimbs of these organisms show differences in external appearance?

The organisms have evolved and their morphological characters have been modified due to the adaptation to the environment. The forelimbs of these organisms exhibit differences in external appearance due to their adaptations to live in their habitats. These changes help the organisms to survive.

Analyse the following illustration and answer the questions : Does the study of homologous organs give similar proof? How?

In the given illustration both the bacteria and human beings store energy in the form of ATP molecules in their bodies. The genes determine the hereditary traits in these organisms. Homologous organs can be characterised as organs from various animals that have the same structure but perform different functions. With the help of studying these organs, it becomes evident that there was a common ancestor for all these living beings. Comparative morphology also indicates proof of evolution.