Final answer:
The left atrium receives oxygen-rich blood from the lungs and pumps it into the aorta.
Step-by-step explanation:
The left atrium receives oxygen-rich blood from the lungs. This blood passes through the bicuspid valve to the left ventricle where the blood is pumped into the aorta. The aorta is the major artery of the body, taking oxygenated blood to the organs and muscles of the body.