Chapter 32, Problem 9STP

Summary Introduction

To write:

The difference between the movement of an S-shaped pattern fish and that of the fish that moves its tail only.

Introduction:

Fishes swim with the help of the movement of their tail back and forth. When they stretch their muscles on one side of the body and they relax the muscles on the other side. Fishes push themselves through the water usually with their back fin.

Explanation of Solution

Fishes swim by pushing their body against the water. They got a flexible backbone and powerful muscles that move their body in S-shaped curves. The opposite movements to the left and right cancel each other out, and the fish is pushed forward.

Movement of the tail side to side helps the fishes with streamlined bodies and caudal fin or tail to move rapidly through the water. This helps in moving the fish like rowing a boat. Ostraciiform is a group of fishes that employs caudal locomotion where only the tail fin oscillates itself creating a thrust.

Conclusion

The flexible backbone and powerful muscles of S-shaped pattern fishes help them to move their body in S-shaped curves. While the caudal fin or tail helps the fishes with streamlined bodies to move in the water.