How Does Your Heart Work?

Apr 13, 2018

How does your heart keep you alive? How does it pump blood? Why is blood so important? Why do children have heart surgeries? Why is a baby's heartbeat faster before it's born? Why does blood rush to your head when you're upside down? Why can you feel your heart in your head when you're lying still or under water?

In this episode of But Why, we're going talking about a very special muscle! It keeps us alive and it has its own special rhythm: the heart. Pediatric cardiologist Dr. Jane Crosson from Johns Hopkins Hospital answers questions about the heart.


"How is blood made?" - Luke, 6, Georgia

"Blood is made in your bones," Dr. Crosson says. If you were to look inside the center of your bones, you'd see that the inside is red. That's marrow. "That's where the blood is made, and it gets out of the bones and into the blood stream, to keep oxygen and food moving around."

"How do hearts keep you alive?" -Isabel, 5, California

"Once the blood is made, the heart's job is to pump it around all through your body, because the blood is there to give all of the food and the oxygen, which keeps your body alive, to deliver all of that stuff to all of the parts of your body, all the way down to your toes, your fingers into your stomach and your brain and everything else," Dr. Crosson says.  

A heart is a pump, it keeps that blood flowing. Without your heart, your blood wouldn't get to where it needs to go.

Listen to the full episode to learn more about how hearts work.