Blood is a life-and-death issue.
How does blood keep you alive? Every second, blood is delivering vital nutrients, oxygen, and other chemicals to all your organs. It also washes away wastes. What’s more, blood can cool you down or warm you up, as needed. It’s your best weapon against germs and other tiny threats. Your blood makes microscopic defenders called antibodies. They coat germs so white blood cells can kill them.
But the same liquid that keeps you alive can also kill you. Blood can quickly spread poisons and other bad things through your whole body. Deadly diseases travel from one body to another through the bloodstream. Your blood may not have the right kinds of defenders to protect you. Or it might not have enough of them.
How can blood both give life and take it away? Read this “life-and-death” issue to find out!
