CIRCULATORY SYSTEM

The heart is a hollow, muscular organ that maintains blood circulation throughout the body. Learn how the circulatory system - your heart, blood vessels and blood - bring nutrients to the body.

How much do you know about the human body?

FPO

Featured

What causes the sound of a heartbeat?

Lub-dub, lub-dub, lub-dub, that's usually the sound of a happy heart. But what's responsible for that steady, comforting beat, and what if your heart doesn't sound like that?

1-10 of 13
  • 1
  • 2
1-10 of 13
  • 1
  • 2

More To Explore

  • Most Popular

Don't Miss