Chapter 28, Problem 17A

Summary Introduction

To infer:

The situation in which the trout would be able to conserve energy

Introduction:

Fishes are vertebrates with backbones and nerve cords that are expanded into brains. There are four classes of fishes; two classes of jawless fishes; lampreys and hagfishes, the cartilaginous sharks and the bony fishes. Trout is a bony fish. They are well adapted for swimming in water.

Since the white dots indicate no muscle activity, the fish in the 4^th situation swimming behind the barrier would be able to conserve energy.

  

Fishes move through water by contracting the muscle groups located on either side of their bodies. According to the given experiment, trout are swimming in free stream flow and behind a barrier.

In situation 1, the trout in free flowing stream uses little muscle power as one orange dot is present in the anterior part. The one behind a barrier also uses little muscle power in the anterior part.

In situation 2, the trout in free flowing stream uses moderate muscle power as one red and one orange dot are present in the anterior part. The one behind a barrier also uses some muscle power.

In situation 3, the trout in free flowing stream uses intense muscle power as three red dots are present and only one white dot is present. The one behind a barrier has only one orange dot so uses little muscle power.

In situation 4, the trout in free flowing stream uses very little muscle power as three white dots are present and one orange dot is present in the tail end. The one behind a barrier does not use any muscle power as four white dots are present.

Hence, it is clear from the given diagram that the trout in the 4^th situation swimming behind the barrier would be able to conserve energy.

Answer to Problem 17A

Since the white dots indicate no muscle activity, the fish in the 4^th situation swimming behind the barrier would be able to conserve energy.

Explanation of Solution

  

Fishes move through water by contracting the muscle groups located on either side of their bodies. According to the given experiment, trout are swimming in free stream flow and behind a barrier.

In situation 1, the trout in free flowing stream uses little muscle power as one orange dot is present in the anterior part. The one behind a barrier also uses little muscle power in the anterior part.

In situation 2, the trout in free flowing stream uses moderate muscle power as one red and one orange dot are present in the anterior part. The one behind a barrier also uses some muscle power.

In situation 3, the trout in free flowing stream uses intense muscle power as three red dots are present and only one white dot is present. The one behind a barrier has only one orange dot so uses little muscle power.

In situation 4, the trout in free flowing stream uses very little muscle power as three white dots are present and one orange dot is present in the tail end. The one behind a barrier does not use any muscle power as four white dots are present.

Hence, it is clear from the given diagram that the trout in the 4^th situation swimming behind the barrier would be able to conserve energy.