Chapter 15, Problem 17A

Summary Introduction

Introduction:

Evolution can be defined as the unrolling of nature that brings about an orderly change from one form to another which results in the descendants to become different from the ancestors.

Homology is similarity between organs of different organisms based on common structural organization or common embryonic origin. Homologous organs are those which have same structure but perform different functions. Homology confirms divergent evolution or adaptive radiation.

Answer to Problem 17A

Correct answer:

Option (D) A whale’s flipper and a bird’s wing.

Explanation of Solution

Explanation correct answer; Option (D) Whale’s flipper and a bird’s wing are examples of homologous organs as they have same structure but perform different functions.

Explanation incorrect answer; Option (A) Butterfly’s wing and a bat’s wing are examples of analogous organs. As both are organs for flying but bat’s wing contains bones and Butterfly wings doesn’t have bones.

Option (B) Moth’s eye and cow’s eye are both have different structure but both acts as organs of visual system.

Option (C) Beetle’s leg and a horse’s leg both helps in locomotion but their structures varies as beetle leg doesn’t have any bone but horse have bones in its legs. Hence, it shows convergent evolution.