What Does the Heart Do? The heart is a pump, usually beating about 60 to 100 times per minute. With each heartbeat, the heart sends blood throughout our bodies, carrying oxygen to every cell. After ...

Every single person has a skeleton made up of many bones. These bones give your body structure, let you move in many ways, protect your internal organs, and more. It's time to look at all your bones — ...

The male reproductive system is made up of the parts inside and outside the body that help a male make a baby. Both the male and female reproductive system are needed for this. The male reproductive ...

How much do you know about the urinary system, which makes pee? Find out by taking this quiz!

How much do you know about your bones? Find out by taking this quiz!

Kids who have vision loss that can’t be fixed with glasses, contacts, or other methods have a visual impairment. They may have complete vision loss (blindness) or partial vision loss. Visual ...

Your eyes see, but how does vision happen? Find out how the eyes and brain work together in this eye video.

Testicular torsion is an emergency condition. It happens when the spermatic cord, which provides blood flow to the testicle, rotates and becomes twisted. The twisting cuts off the testicle's blood ...

An erection is when the penis gets hard because sponge-like tissue in it fills with blood. Erections tend to make the penis get bigger and stand away from the body. Erections can go away on their own ...

We see and hear about hearts everywhere. A long time ago, people even thought that their emotions came from their hearts, maybe because the heart beats faster when a person is scared or excited. Now ...

All-terrain vehicles, or ATVs, are off-road vehicles used for things like farm work and riding on trails. In most states, it's legal for teens to ride them, even without a driver's license. But with ...

What Do Substance Abuse and Addiction Mean? The difference between substance abuse and addiction is very slight. Substance abuse means using an illegal substance or misusing a legal substance.