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 ...

A nosebleed happens when tiny blood vessels inside the nose break and blood comes out of the nostrils. Nosebleeds are common in children, especially kids 3 to 10 years old. Most aren't a sign of ...

Por lo general, los médicos no pueden saber si una persona se ha estado masturbando (tocarse o frotarse los genitales porque le gusta lo que se siente). La única manera de que los médicos sepan si una ...

Health care providers can treat medical problems and sometimes cure them. But how is a "treatment" different from a "cure"? A treatment is something that health care providers do for their patients to ...

What Is a VP Shunt? A ventriculoperitoneal (VP) shunt is a thin plastic tube that helps drain extra cerebrospinal fluid (CSF) from the brain. CSF is the saltwater that surrounds and cushions the brain ...

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

Most of us know that some teens cut. But cutting — using a sharp object like a razorblade, knife, or scissors to make marks, cuts, or scratches on one's own body — is just one form of self-injury.

What Is Abusive Head Trauma? Abusive head trauma is a head or neck injury from physical child abuse. It happens when someone shakes a baby or hits the baby against something hard. Most cases happen ...

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 ...

Your body has a "highway" system that sends blood to and from your body parts. It's called the circulatory system and the roads are called arteries and veins. Arteries, which usually look red, carry ...

A wet dream — also called a nocturnal emission — is when a male ejaculates or "cums" while sleeping. During ejaculation, semen (the fluid that carries sperm) comes out of the penis. When you wake up ...

What's the Digestive System? Even before you eat, when you smell a tasty food, see it, or think about it, digestion begins. Find out how the digestive system works, from start to finish, in this video ...