The circulatory system is composed of the heart and blood vessels

The circulatory system is composed of the heart and blood vessels, it also is known as the cardiovascular system and or the vascular system. The circulatory system works by disseminating blood and other important cells around the body. It transports nutrients, such as amino acids and electrolytes, oxygen, carbon dioxide (the gas produced when people or animals breathe out), hormones, to and from the cells in the body to provide nourishment, help in fighting foreign diseases in the body, stabilize temperature and pH (a number on a scale of 0 to 14 which shows how acid or alkaline a substance is), and sustain homeostasis.