Closed Circulatory System


Sharks, like other fish, possess a closed circulatory system. This system is responsible for circulating blood from the heart to the gills, and then to the rest of the tissues of the body. The total distance traveled in the closed circulatory system of an animal is roughly proportional to the size of the animal. The air exchange membrane at the gills of a shark roughly one cell thick, leading to a maximum pressure that can pass through the gills without rupturing them.

The closed circulatory system of any organism acts as a series of pipes responsible for the transport of blood that adheres to Bernoulli's principles regarding the flow of fluids through a tube.