Chemistry

the digestive system breaks down food into nutrients through the digestive tract and other accessory organs. the small intestine diffuses those nutrients through its wall and into the bloodstream. the circulatory system provides the digestive tract with multiple capillaries that transport the nutrients around the body to other tissues and organs. without the circulatory system, the nutrients the digestive system obtained from food would stay in one place.

the respiratory system takes in oxygen and releases carbon dioxide. for this to happen gas exchange needs to occur. the circulatory system contains blood which carries carbon dioxide. the carbon dioxide diffuses from the blood to the alveoli and the oxygen is inhaled through the nasal cavity or mouth into the blood. the oxygen is transported around the body with the help of the heart’s ventricle which pumps blood.

the spinal cord carries impulses to the brain which coordinates intellectual activity. the peripheral nervous system, which is connected to the brain and spinal cord (central nervous system) takes those impulses and allows the muscles to contract or relax depending on the response needed.