Your heart pumps it throughout your body, and without it, you wouldn't be alive! It's blood, and it performs many important jobs to keep your body running smoothly!
For one thing, blood carries oxygen throughout the body once you breathe it in from the air. Blood also delivers important nutrients and other helpful substances to your body's many cells. But it's not just about what blood brings you, it's also about what blood takes away! Your blood carries carbon dioxide and other waste to body parts like the kidneys so this waste can move out of your body. Your blood also contains important cells that fight infection, such as illnesses caused by bacteria and viruses.
As you can see, your blood keeps you healthy in many different ways!
Blood is made of different types of cells, like red blood cells, white blood cells, and platelets. These cells are carried by the fluid part of your blood called plasma. Each type of blood cell (and the plasma in which it is suspended) performs a special job for your body, and you learned about these jobs above! Blood gets its red color from a protein in the red blood cells called hemoglobin!