Question

Perception of visual cues is essential for survival of most animals. A scientist analyzes the vision receptor molecule in invertebrates and vertebrates. The results show that the genes for opsin, the protein part of the photoreceptor, share strong homology in the regions that code for domains involved in light response. Which of the following conclusions is the MOST likely?

A. The receptor molecules will be structurally different but respond to the same light cues.

B. The receptor molecule will be similar in invertebrates and vertebrates because of convergent evolution.

C. The receptor molecules will be different because invertebrates and vertebrates perceive visual cues in different environments.

D. The receptor molecules will be similar in invertebrates and vertebrates because they appeared early in evolution.

Answer 1

C is the answer.

Explanation:

It is given that string homology is found between the gene sequence of invertebrates and vertebrate's opsin genes. Here the homology refers to the same sequences in the genes but these genes diversify to produce different molecules because they faced different environmental conditions fcaed by vertebrates and invertebrates.