Deoxygenated, waste-laden blood flows into the left atrium f…

Deoxygenated, waste-laden blood flows into the left atrium from the veins of the body. It is then pushed into the left ventricle, which pumps the blood out to the lungs. In the lungs , carbon dioxide leaves the blood and is exhaled while oxygen enters the blood. The oxygenated blood returns to the left atrium of the heart. The blood is pushed into the left ventricle, which pumps the blood out of the heart to travel through the body in the arteries.