The circulatory (SIR cyoo luh TOR ee) system is the body’s transport system. The circulatory system supplies the cells of the body with food and oxygen. At the same time, it carries carbon dioxide and other wastes away from the cells. The circulatory system also helps regulate the temperature of the body and carries substances through the bloodstream that help protect the body from disease.
The heart is the muscle that acts as a pump for the circulatory system. The blood vessels then carry the blood through the body. Arteries (shown in red) are blood vessels that carry blood away from the heart. Veins (shown in blue) are blood vessels that return blood to the heart.
Each time your heart beats, it forces blood through your arteries, causing the blood to push against the artery walls. The force of the blood pushing against the walls of the blood vessels is called blood pressure.
Question
How can you tell how fast your heart is pumping?
Count your heart rate, also called your pulse. You can usually feel your pulse by pressing lightly against the inside of your wrist or against your neck with a couple of fingers. Or you can listen to your heart with a stethoscope and count the beats.
