Rocket squeezes a water bottle over a bucket. Water squirts out in a fast stream.
"I built a pump!" he cheers. "Squeeze, let go, squeeze again."
Raven watches the bottle fill back up. "What do you notice?" she asks. "Your body has a pump like that."
Nova floats near Rocket's chest. "Think about a muscle that squeezes all day and all night," she says.
Your heart is really a muscle. It works like a pump.
It sits a little to the left of the middle of your chest.
Make a fist. Your heart is about the size of your fist.
Before each beat, your heart fills with blood. Then it squeezes to push the blood along.
It does this all day and all night, your whole life long.
Blood is the body's delivery helper.
It brings oxygen and nutrients to every part of your body.
Nutrients are the useful parts of food. Oxygen comes from the air you breathe.
Blood also carries away waste, like the gas carbon dioxide.
| Blood brings | Blood carries away |
|---|---|
| oxygen | carbon dioxide |
| nutrients from food | other waste |
| Statement | True or false? |
|---|---|
| The heart pumps blood around the body. | ? |
| The heart rests all night while you sleep. | ? |
| Blood brings oxygen to the body. | ? |
| Blood carries away waste. | ? |
Great pumping, scientist! Tomorrow we peek inside the heart to find its four rooms.