Get to know the functions of your heart, blood vessels, and blood itself and how they work together to maintain your health.

You remember how Dorothy, Toto, and the rest of the gang were trying to make their way to see the Wizard of Oz? That’s kind of how veins work in relation to your heart. Your heart is the wizard, and ...

One of the most important preconditions for the development of terrestrial vertebrates in the course of evolution was the formation of the two halves of the circulatory system. Aquatic ancestors ...