Circulatory System
The circulatory system consists of cardiovascular and lymphatic divisions.
The cardiovascular division transports materials within the body and includes the heart, blood and blood vessels. Blood contains nutrients and oxygen to provide energy to allow the cells of the body to perform work.
The lymphatic division helps maintain fluid balance and aids in defending against infectious diseases. The lymphatic system includes the lymph glands and vessels, and the spleen, thymus and tonsils.