Hepatitis B is a liver infection caused by the hepatitis B virus (HBV). In some people, HBV stays in the body, causing long-lasting disease and long-term liver problems. The younger someone is when ...

Fatty acids are the building blocks of the fat in our bodies and in the food we eat. During digestion, the body breaks down fats into fatty acids, which can then be absorbed into the blood. Fatty acid ...

What Is a Perforated Eardrum? A perforated eardrum is a tear or hole in the ear's tympanic membrane (the eardrum). A perforated (PER-fer-ate-id) eardrum can hurt, but most heal in a few days to weeks.

What Does the Immune System Do? If you've ever wondered how your immune system works, this movie is for you!

If your child has a serious illness like cancer or a chronic (ongoing) condition like asthma, your doctor might talk to you about enrolling your child in a clinical trial. A clinical trial is a study ...

It's easier to agree than disagree. But we can learn a lot from conversations where we don't see eye to eye — if we can listen and talk rationally, that is. Unfortunately, many us either shy away ...

What Are the Lungs and Respiratory System? The lungs and respiratory system allow us to breathe. They bring oxygen into our bodies (called inspiration, or inhalation) and send carbon dioxide out ...

Teens are busy, and often skip meals. Even if you eat three meals a day, you may still feel hungry between meals. Either way, it can be tempting to grab something fast, like cookies, chips, and candy.

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 ...

Reproduction is the process by which organisms make more organisms like themselves. But even though the reproductive system is essential to keeping a species alive, unlike other body systems, it's not ...

Take good care of yourself. Give your body and mind the exercise, food, and sleep you need every day. It’s easier to handle things when you feel strong and rested. Stretch and relax with yoga and ...

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 ...