Your circulatory system functions with the help of blood vessels that include arteries, veins and capillaries. These blood vessels work with your heart and lungs to continuously circulate blood through your body. Here’s how:
- The heart’s bottom right pumping chamber (right ventricle) sends blood that’s low in oxygen (oxygen-poor blood) to the lungs. Blood travels through the pulmonary trunk (the main pulmonary artery).
- Blood cells pick up oxygen in the lungs.
- Pulmonary veins carry the oxygenated blood from the lungs to the heart’s left atrium (upper heart chamber).
- The left atrium sends the oxygenated blood into the left ventricle (lower chamber). This muscular part of the heart pumps blood out to the body through the arteries.
- As it moves through your body and organs, blood collects and drops off nutrients, hormones and waste products.
- The veins carry deoxygenated blood and carbon dioxide back to the heart, which sends the blood to the lungs.
- Your lungs get rid of the carbon dioxide when you exhale.