Body Explorer
Your body is full of parts that work together all day, even while you sleep. Tap a part of the body, or pick a button, to find out what it does, a cool fact, and a safe thing to try.
Brain and nerves
What it does: Your brain is the control center. Nerves are like wires that carry messages between your brain and every part of your body, so you can think, feel, and move.
Cool fact: Your brain is only about 2% of your body weight, but it uses about 20% of your body's energy. Source: Raichle & Gusnard, PNAS, 2002
Try this: Close your eyes and touch your nose. Your brain knows where your hand is, even without looking.
Heart and blood
What it does: Your heart is a pump. Every beat pushes blood through tubes called blood vessels, carrying oxygen and food to every cell.
Cool fact: Your heart is about the size of your fist. Source: NIH NHLBI, The Heart
Try this: Gently place two fingers on the inside of your wrist and feel your pulse. Do 10 jumping jacks and feel it again. What changed?
Lungs and breathing
What it does: When you breathe in, air travels through your nose and down into your lungs. Oxygen moves into your blood, and you breathe out a gas your body does not need.
Cool fact: Your nose cleans, warms, and moistens air before it reaches your lungs. Source: NIH StatPearls, Physiology, Nasal
Try this: Sit still and count your breaths for one minute. Then count again after walking around the room.
Stomach and gut
What it does: Your stomach and intestines break food into tiny pieces your body can use. Helpers like the liver and pancreas add special juices.
Cool fact: Your liver makes bile, a juice that helps break down fats in food. Source: NIH NIDDK, Your Digestive System
Try this: Take one bite of food and count how many times you chew before you swallow.
Kidneys
What it does: You have two kidneys, each about the size of a fist, just below your ribs on each side of your spine. They clean your blood and make urine to carry waste away.
Cool fact: Your kidneys filter about 150 quarts of blood every day. Only 1 to 2 quarts become urine. Source: NIH NIDDK, Your Kidneys & How They Work
Try this: Drink water when you feel thirsty. Pale yellow pee usually means you are drinking enough.
Bones
What it does: Bones are your body's frame. They hold you up, protect soft parts like your brain and heart, and work with muscles so you can move.
Cool fact: A grown-up skeleton usually has 206 named bones. Source: National Cancer Institute SEER Training
Try this: Gently feel the bones in your fingers, your elbow, and your knee. Can you find where they bend?
Muscles
What it does: Muscles pull on bones to move you. Some muscles, like the ones in your heart and stomach, work all by themselves.
Cool fact: Iron from food helps carry oxygen in your blood and to your muscles. Source: NIH Office of Dietary Supplements, Iron
Try this: Bend your arm and make a muscle. Feel how your upper arm gets firm when the muscle works.
Skin
What it does: Skin is your body's waterproof coat. It keeps germs out, helps keep you warm or cool, and lets you feel touch.
Cool fact: Your skin is your body's largest organ. Source: MedlinePlus, Skin Conditions
Try this: Look closely at your fingertips. The swirls are your fingerprints, and nobody else has the same ones.
This is general information. For your own health, talk to a doctor.