A drop of blood can zip all through you in a minute or less.
So can poisons. These might be snake venom, bad chemicals, or other toxins. Germs zip through you just as quickly. Invaders are always rushing through your blood vessels. Your white blood cells are always battling them. Organs such as your liver and spleen fight them too.
In a healthy body, cells and organs win easily. But sometimes your best defenses aren’t enough to keep your own blood from harming or even killing you. Poisons can outnumber defenders. 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?
