The cardiovascular system consists of the heart, blood vessels, and blood. Its primary function is to transport nutrients and oxygen-rich blood to all parts of the body and to carry deoxygenated blood ...

The heart is a unidirectional pump. Valves are present to prevent the backflow of blood. This unidirectional flow of blood through the heart shows that mammals have a double circulatory system. This ...

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 ...