Function of Cardiovascular System
It’s the main function of the cardiovascular system to provide energy and nutrients to every part of your body so you can keep functioning efficiently. The arteries are the fuel pipes, and the heart itself is the engine. The other function of the cardiovascular system is to remove waste products from your cells and transport them out of the body – and this is done through your veins. Every function of the cardiovascular system is controlled by your autonomic nervous system, meaning that it keeps on running by itself without your conscious control, on ‘auto pilot’.
The heart
The heart is a muscle whose main function is to keep pumping your blood continuously around your body. Nerve fibres attached to the heart muscle can alter the rate of the beat according to your body’s needs – for instance, if you are running, you are working your muscles harder, so your heart begins to beat faster, which enables your blood to transport energy and nutrients to your muscles more quickly.
Systemic and Pulmonary circulation
Your systemic circulatory system carries oxygenated blood from the heart to every cell of your body through your arteries, and carries de-oxygenated blood back to the lungs via the heart through your veins. Your pulmonary system carries blood from the heart to the lungs, where it is re-oxygenated, and where carbon dioxide and waste products are removed from the blood before it returns to the heart to be pumped around the body. The pulmonary system is a one-way system, like the systemic system, but the other way around: it's the pulmonary artery that carries de-oxygenated blood to the lungs, and the pulmonary vein that brings oxygen-rich blood back to the heart.