what does the circulatory system composed of
The main components of the human circulatory system are the heart, the blood, and the blood vessels. The circulatory system includes: the pulmonary circulation, a loop through the lungs where blood is oxygenated; and the systemic circulation, a loop through the rest of the body to provide oxygenated blood.he circulatory system includes: the pulmonary circulation, a loop through the lungs where blood is oxygenated; and the systemic circulation, a loop through the rest of the body to provide oxygenated blood.