Well, the blood has to be kept moving around all the time because it's the body's delivery system. Every possible part of the body has to be supplied with oxygen and food and water, and the veins and ...

In a freakish step toward the Fountain of Youth, scientists have discovered the protein responsible for young blood's effect on older mice. ByAllison Eck Monday, May 5, 2014 NOVA NextNOVA Next ...

The circulatory system includes the heart, blood vessels and blood, and is vital for fighting diseases and maintaining homeostasis (proper temperature and pH balance). The system's main function is to ...

Here on Earth, a person's blood tends to pool in the legs because of gravity (the leg veins have valves that help to maintain blood flow from the legs back up to the heart). Things are different in ...