Chapter 28, Problem 11A

Summary Introduction

To fill:

The name of the four-footed animal with legs that have feet and toes that have joints.

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 found.

Answer to Problem 11A

A tetrapod is a four-footed animal with legs that have feet and toes that have joints.

Explanation of Solution

There are three main class of fishes based on their body structure. These are jawless fishes, cartilaginous fishes, and bony fishes. The bony fishes include both lobe-finned and ray-finned fishes. There are only eight species of lobe-finned fishes living today. Tetrapod is a small group of lobe-finned fishes which is now extinct. A tetrapod has four feet. They have legs that have joints in feet and toes.

Conclusion

A tetrapod is a four-footed animal with legs that have feet and toes that have joints.