Even though insects are very diverse in some ways, they are remarkably similar in others. The insect head is formed from 6 fused segments and carries the compound eyes, the antennae and the mouthparts. The mouthparts are modified according to the diet, some for sucking or lapping of liquids and others for the chewing and grinding of more solid foods. The last 2 thoracic segments usually bear the winds, one pair on each segment. The abdomen is made up of 11 segments and contains the digestive and reproductive organs.
Insects are very important to man, both as a competitor and as a helper.
Some insects also vector diseases to men and his animals. Malaria, an insect borne disease, is responsible for about 2,000,000 human deaths per year. If all the honeybees were removed from the earth our ecosystem would rapidly be destroyed. Many other insects render valuable service in small unseen ways. Scientists presently recognize 28 Orders of the Class Insecta.