Physiology of Finfish and Shellfish (2+1)

3.2.5. Cardiac muscle

The heart is the pump that keeps blood circulating throughout the body and thereby transports nutrients, break down products, antibodies, hormones and gases to form tissues. The heart consists mostly of muscle, the myocardial cells (collectively termed the myocardium), arranged in several ways that set it apart from other types of muscle. The outstanding characteristics of the action of the heart are its contracticity, which is the basis for its pumping action, and the rhythmicity of the contraction. In all hearts the pumping action results from the contraction of atleast one chamber.