The newly oxygen-rich blood (shown in red) returns to the heart and enters the left atrium. Blood flows through the left atrium into the left ventricle. The left ventricle pumps the oxygen-rich ...

The circulatory system consists of one heart, five liters of blood, and approximately 96,000 kilometers of blood vessels, responsible for transporting nutrients and waste throughout the body. Water ...

The agency OK’d an artificial vessel to restore blood flow in patients, even though its own scientists flagged questionable ...

Your heart is an exquisitely engineered pump ... around the circulatory system and digestive system in the human body, through blood vessels and into mitochondria. Human fertilisation.

blood flows into the heart from a vein, goes into an atrium, then a ventricle, and out through an artery. The valves prevent the blood flowing backwards. The heart is relaxed and blood flows into ...

Originally appeared on the NOVA Web site Cut to the Heart. Let's get straight to the heart of the matter—the heart's job is to move blood. Day and night, the muscles of your heart contract and ...