Later, when she lays her eggs, the sperm enter the eggs as they leave her body. Insect eggs have a variety of shapes and color patterns, but most are oval or round and are white or cream colored. The number of eggs laid varies greatly from one species to another. A female insect probably lays an average of 100 to 200 eggs during her lifetime. Both man and insect live almost everywhere, eat all kinds of food, and use all kinds of materials to build homes so they constantly live in conflict.
Some insects seriously affect man's health and are parasitic on man and other animals.
Insects that feed on human or animal blood can carry disease in their salivary juices and spread the disease to other animals. Many insects irritate us without disturbing our health. Some bite and sting, and some people are allergic to them. Other insects are injurious to our agricultural crops, food products, clothing, and wooden buildings. So far human beings have had only partial success in defending themselves against insects.