Your Amazing Body
This is your skin! It's your body's coat. Tap anywhere to learn about it, or try the X-ray to peek underneath.
Every part of the skin 0 of 16 explored
About your skin (Integumentary system)
Skin is the biggest organ you have. It wraps all of you like a stretchy, waterproof coat that fixes itself when it gets a scrape.
Your skin, hair and nails work together as one team. Scientists call that team the integumentary system (in-TEG-yoo-MEN-tuh-ree). It keeps germs out and water in, keeps you warm or cool, and lets you feel a hug, a raindrop or a hot cup.
Skin comes in many beautiful shades, and every one of them works the same way.
- Layers3
- Grown-up skinabout 20 square feet
- New top layerabout every month
- Skin: Skin is the stretchy coat that covers all of you and keeps the outside out.
- Top layer (Epidermis): The top layer is the part of your skin you can see and touch.
- Middle layer (Dermis): The middle layer is the busy part of your skin, full of blood, hair roots and feelers.
- Cushion layer (Hypodermis): The cushion layer is soft padding under your skin that keeps you warm and safe.
- Skin color (Melanin): Skin comes in many beautiful shades, from very light to very dark, and every one is great.
- Freckles and moles: Freckles are tiny spots of extra color, like sprinkles the sun brings out on your skin.
- Hair: Hair grows out of tiny pockets in your skin, and cutting it doesn't hurt one bit.
- Nails: Nails are hard little shields on your fingers and toes, made of the same stuff as hair.
- Fingerprints: Fingerprints are tiny swirly lines on your fingertips, and nobody else in the world has yours.
- Sweat (Sweat glands): Sweat is salty water your skin makes to cool you down when you get hot.
- Goosebumps: Goosebumps are tiny bumps that pop up when you're cold or feel a big feeling.
- Feeling touch (Nerve endings): Your skin is full of tiny feelers that tell your brain about every poke, tickle and hug.
- Cuts, scabs and bruises: When you get a cut, your body builds a scab like a bandage and fixes the skin underneath.
- Sun and your skin: The sun's invisible rays can burn your skin, so sunscreen, hats and shade keep you safe.
- Lips: Your lips have extra thin skin, and they help you talk, eat, smile and blow bubbles.
- Belly button (Navel): Your belly button is where a soft tube brought you food and oxygen before you were born.
Five layers of you
- SkinIntegumentary systemSkin is the biggest organ you have. It wraps all of you like a stretchy, waterproof coat that fixes itself when it gets a scrape.16 parts to explore
- MusclesMuscular systemEvery move you make, from a jump to a blink to a smile, is muscles at work. Muscles are made of long, thin threads called fibers that can squeeze shorter.24 parts to explore
- BonesSkeletal systemYour skeleton is the frame that holds you up, like the beams inside a house. Without it you'd flop like a jellyfish.24 parts to explore
- Heart & BloodCirculatory systemYour heart is a strong muscle pump about the size of your fist. Every beat pushes blood through a giant network of tubes called blood vessels.18 parts to explore
- OrgansOrgansAn organ is a body part with a big job. Your brain thinks, your lungs breathe, your stomach mashes food, and your kidneys clean your blood.23 parts to explore
Your body in numbers
- 🖐️ Layers3
- 🖐️ Grown-up skinabout 20 square feet
- 🖐️ New top layerabout every month
- 💪 Musclesmore than 600
- 💪 Biggestgluteus maximus
- 💪 Tiniestabout 1 millimeter
- 🦴 Grown-up bones206
- 🦴 In your hands and feetmore than half
- 🦴 Longestfemur
- ❤️ Heartbeats a dayabout 100,000
- ❤️ Heart rooms4
- ❤️ One trip around youabout a minute
- 🧠 Biggest organ insideliver
- 🧠 Small intestineabout 20 feet
- 🧠 Brain cellsabout 86 billion
🙋 Questions kids ask about the body
Does my heart ever stop to rest?
Not really. It rests for a tiny moment between every beat, and it slows down while you sleep, but it keeps beating your whole life. More about the heart →
Does my brain ever sleep?
Not really. Your brain stays busy all night. It keeps you breathing, sorts your memories and makes your dreams. More about the brain →
Do bones feel pain?
Yes. A thin skin on the outside of each bone has nerves, so a hurt bone feels sore. That soreness tells you to rest it and tell a grown-up. More about the skeleton →
Is skin really an organ?
Yes! An organ is a body part with a special job. Skin has many jobs, so it's an organ, and the biggest one. More about the skin →
Why does my tummy growl?
Your stomach muscles squeeze air and juice around. It happens all the time, but you hear it most when your stomach is empty. More about the stomach →
Why do my legs feel wobbly after running a lot?
Your muscles used up a lot of energy and need a rest. Sit down, drink some water, and they'll feel better soon. More about the how muscles work →
Why is blood red?
Red blood cells are full of hemoglobin, which holds oxygen and is red. More oxygen makes it brighter red. More about the blood →
Why do I breathe faster when I run?
Your hard-working muscles need more oxygen, and they make more carbon dioxide. Breathing faster brings in oxygen and gets rid of the waste gas. More about the lungs →
Does losing a tooth hurt?
Usually not much. By the time a baby tooth falls out, most of its root has dissolved, so it's only hanging on a little. More about the teeth →
Why is sweat salty?
Sweat is mostly water with a little salt in it. Your body uses salt, and some comes out along with the water. More about the sweat →
Why are my eyes a different color than my friend's?
Eye color depends on how much of a coloring called melanin is in your iris. Lots of it makes brown eyes, and less makes blue, green or gray. You get your eye color from your family. More about the eyes →
Is marrow the soft stuff inside a soup bone?
Yes! The soft middle of an animal bone is marrow too. Yours does an important job: making new blood. More about the bone marrow →
Grown-ups: The Body is a free, interactive human body for kids. Five diagrams (skin, muscles, bones, heart and blood, and organs) peel away layer by layer, and every one of about a hundred parts has its own page with a close-up drawing, plain-words facts checked against children's health sources, questions kids ask, and a three-question quiz read aloud. Nothing is typed or sent; what a child has explored stays on this device. The reproductive system is left out on purpose.