If you ever put a seashell up to your ear, you hear something like the ocean. Actually, that sound is the echo of the blood moving through your ears!

If you have ever looked at water in a bowl, you will notice that the top of the water is always level. You can pick the bowl up and tilt it a little, but the surface of the water will always be level with the ground.

Inside your ear are "semicircle canals" which help determine balance. They are the small tubes shaped in half circles in the inner ear. They are filled with liquid and lined with hairs. When you tilt your head or body, the liquid in those tubes, just like water in a tilted bowl, levels out. The tiny hairs sense how much the liquid moves and tell your brain. The brain then understands how unbalanced you are, and can figure out how much to compensate to become balanced again.

The semicircle canals can also cause some common problems. For instance, have you ever been sea-sick, car-sick, or air-sick? These feelings are called motion sicknesses. When your body moves around a lot, the semicircle canals are constantly sending different messages to the brain, and the brain begins to get confused. You can become dizzy, and sometimes feel a nauseated. Luckily, there are medicines that can help make you feel better.