Step-by-step explanation:
1) Deoxygenated blood flows from the body into the right atrium of the heart through the superior and inferior vena cava.
2) The right atrium contracts, forcing the blood through the tricuspid valve into the right ventricle.
3) The right ventricle contracts, pumping the blood through the pulmonary valve and into the pulmonary artery.
4) The pulmonary artery carries the deoxygenated blood to the lungs, where it receives oxygen and releases carbon dioxide.
5) Oxygenated blood flows from the lungs into the pulmonary veins.
6) The pulmonary veins carry the oxygenated blood to the left atrium of the heart.
7) The left atrium contracts, forcing the blood through the mitral valve into the left ventricle.
8) The left ventricle contracts, pumping the oxygenated blood through the aortic valve and into the aorta.
9) The aorta distributes the oxygenated blood to the rest of the body.