A drop of blood can zip through your bloodstream in a minute or less.
So can poisons like snake venom and toxic chemicals. Germs can zip through you just as quickly. Invaders are always surging through your blood vessels. Your white blood cells and organs such as your liver and spleen are always battling them.
In a healthy body, cells and organs easily knock out invaders. But sometimes your best defenses aren’t enough to keep your own blood from harming or even killing you. Poisons can outnumber defenders, and germs can actually trick your cells into ignoring them. What kinds of invaders does your bloodstream carry? What happens when your defenses don’t work? What else can go wrong with your blood?
