Chapter 29, Problem 5STP

Summary Introduction

Introduction:

Fishes live in aquatic habitats like lakes, seas, rivers, ponds, etc. Some fishes live in complete darkness at the bottom of the deep ocean whereas others live in the freezing water of the Polar Regions and have special proteins in their blood to keep the blood from freezing. There are about 24,600 species of living fishes are found.

Answer to Problem 5STP

Correct answer:

The correct answer is option (C) keeping a fish upright and balanced.

Explanation of Solution

Explanation/justification for the correct answer:

Option (C) keeping a fish upright and balanced. The lateral line system enables fishes to detect movements in the water and also help to keep them upright and balanced. Through lateral line system they can detect the slightest movement in the water. So, the correct answer is option (C).

Explanation for incorrect answer:

Option (A) detecting chemicals in the water. Fishes have receptors for the sense of smell that enable them to detect chemicals in the water. The olfactory bulbs record and respond to incoming chemical input. So, this is an incorrect option.

Option (B) detecting water pressure changes.The lateral line system helps the fish to detect the slightest movement in the water and keep them upright and balanced. So, this is an incorrect option.

Option (D) sending signals between fishes.Fish interact with noise, like grunts, chirps and pops. The lateral line system enables fishes to detect movements in the water and also help to keep them upright and balanced. So, this is not the correct option.