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 ...

It’s normal for people to masturbate (touch or rub their own genitals because they like the way it feels). Some people do it to relieve stress or tension. It’s nothing to be ashamed of or embarrassed ...

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

Earaches are common in kids and can have many causes. Here’s why they happen and what to do when your child complains of ear pain. Give acetaminophen or ibuprofen as needed to ease pain (check the ...

Have you ever seen liver and onions on a diner menu? If so, we're guessing you said "yuck" and ordered something else. But did you know that there's one liver you don't have to order? It's always ...

Most blood tests take only a few minutes. They’re done at some doctor’s offices, and at community labs, diagnostic centers, and hospitals. A doctor, nurse, or phlebotomist (fleh-BOT-eh-mist, someone ...

Sanfilippo (san-fuh-LEE-po) syndrome is a rare genetic metabolism disorder. A change in a single gene makes a child's body unable to break down certain carbohydrates (sugars). This leads to serious ...

Both the brain and the spinal cord are protected by bone: the brain by the bones of the skull, and the spinal cord by vertebrae, a set of ring-shaped bones. They're both cushioned by layers of ...

Sexually transmitted diseases (STDs) are infections spread from person to person during sex (vaginal, oral, or anal) or close sexual contact. STDs are also called sexually transmitted infections, or ...

How Does Air Enter the Respiratory System? Air enters the respiratory system through the nose or the mouth. If it goes in the nostrils (also called nares), the air is warmed and humidified. Tiny hairs ...

Did you know you have more than 600 muscles in your body? They do everything from pumping blood throughout your body to helping you lift your heavy backpack. You control some of your muscles, while ...

What Is an Umbilical Hernia? An umbilical hernia happens when part of a child's intestines bulges through the abdominal wall inside the belly button. It shows up as a bump under the belly button. The ...