Introduction to the Anthropods

28-1

Exoskeleton

• External skeleton; tough external covering that protects and supports the body of many invertebrates.

Chitin

• Complex carbohydrate that makes up walls of fungi; also found in the external skeletons of arthropods.

Appendage

• Structure, such as a leg or antenna, that extends from the body wall.

Tracheal Tube

• One of many branching, air-filled tubes that extend throughout the bodies of many terrestrial arthropods.

Spiracle

• Small opening located along the side of the body through which air enters and leaves the body of many terrestrial arthropods.

Book Lung

• Organ that has layers of respiratory tissue that is used by some terrestrial arthropods for the exchange of gases.

Malpighian Tubule

• Saclike organ in most terrestrial arthropods that extracts wastes from the blood, adding them to feces that move through the gut.

Molting

• Process in which an arthropod sheds its exoskeleton and manufactures a larger one to take its place.