Chapter 28, Problem 8A

Summary Introduction

To write: The reason why there are more species of vertebrates living in the ocean than there are on land form

Introduction: Vertebrates have a spinal column and advanced cells that grow from the tissue of the nerves. The spinal column is the signature characteristic in vertebrates, also called a vertebral column.

Explanation of Solution

Many fish reproduce by outside fertilization. In a mechanism called spawning, male and female fish drop their gametes close to each other into the sea. Developing embryos get nutrients from food that's contained in the egg yolk. Fishes which reproduce in a single season through external fertilization may gives millions of eggs. Most fish do not shield their eggs or larvae, or care for them. The male fish watch over the fertilized eggs from predators before they have hatched.