Blood is a liquid that circulates throughout the body, carrying oxygen and nutrients to every cell and carrying away waste products. It is pumped by the heart to every part of the body through a network of blood vessels.

There are four main components of blood: red blood cells, white blood cells, platelets and plasma. In addition blood contains various nutrients and minerals and plays a central role in the body’s defense against intruders.

Most people don’t realize the need for blood until they need blood themselves. Please give.