This slide presentation explores the human circulatory system. It begins by explaining why humans need a transport system, as diffusion alone is not effective over long distances. The key components of the human transport system are then introduced as the heart, blood vessels, blood, and lymphatic vessels. The structure and function of the heart is examined in depth, including the chambers and valves. Blood flow through the heart is depicted, with the major blood vessels associated with the heart named. Different blood vessel types are also distinguished.