Body Parts & What They Do Glossary
A
Adenoids (AD-eh-noyds): The adenoids are a patch of tissue in the back of the throat behind the nose. Their job is to help keep you healthy by trapping harmful bacteria and viruses that you breathe in or swallow.
Adenoids fight germs, especially in young kids. But as kids get older, their bodies develop other ways to fight germs, so adenoids are less important. Adenoids usually shrink after a kid turns 5, and they practically disappear by the time a kid becomes a teen.
Airways: The airways in your lungs are like tubes or straws. The air flows in and out of them so you can breathe. They're also called bronchial (BRONG-kee-ul) tubes or bronchi (BRONG-kye).
Anus (AY-nus): The anus is the opening where your bowel movements (also known as poop) come out. In other words, it's the hole in your bottom.
Appendix (uh-PEN-dix): Your appendix is a small pouch attached to your large intestine, in the lower right part of your belly. The purpose of the appendix is not clear, but sometimes it gets inflamed and causes appendicitis.
B
Body Types: Bodies come in all shapes and sizes, and that's why we have different body types. Body types are just different kinds of bodies. Some people are tall and thin; others are shorter and heavier. Whatever your body type is, take good care of your amazing body!
Boogers (BU-gurz): Got your finger up your nose? (We hope not!) If you do, you can probably feel a booger. Boogers are made of dried mucus, dust, pollen, and dirt. They can be squishy or hard, but they do an important job — they help keep that bad stuff from getting into your lungs. Boogers are full of germs, so it's a good idea not to pick them (blow them out into a tissue instead).
Borborygmus (bor-buh-RIG-mis): How do you know it's lunchtime? Your stomach just made a growling sound called borborygmus. That's because when the muscles in your digestive system move food, liquid, and gas through your stomach and small intestine, it produces a rumbling sound. Borborygmus can happen any time, but it's louder and happens more often when you're hungry because your stomach is empty. Growl!
Bowels (BOW-uls): Bowels are your intestines, and bowel movements are the stuff that's in them (otherwise known as poop). It might sound yucky, but your bowels have an important waste-removing job!
C
Canine Teeth (KAY-nine): Woof, woof, what's that tooth? Your canine teeth are the pointy ones next to your front teeth. You have two on top and two on the bottom. Because they're sharp, they help tear food. Grrrr!
Cartilage (KAR-tul-ij): Touch the tip of your nose or the top of your ear — that's cartilage. This strong, flexible connective tissue supports and protects bones. It's bendable, not hard like bone, and is found in various parts of your body, including between bones so they don't rub together.
Cells: Ever wonder what you're made of? The simple answer is cells. These are the smallest building block of every living thing on our planet, including you. You have trillions of cells in every part of your body that do everything from changing your food into energy to keeping you healthy by killing germs.
Cerebral Cortex (seh-REE-brel KOR-teks): Also known as gray matter, this term describes the brain's outer layer. The cerebral cortex is involved in complex brain functions, such as language and information processing.
Cochlea (KOH-klee-uh): The cochlea is a hollow tube deep in your ear. It looks like a spiral-shaped snail shell and plays an important part in helping you hear: It changes sounds into nerve messages and sends them to your brain. After the eardrum takes in a sound, the sound gets turned into a vibration that travels to the cochlea. There, the tiny hairs that line the cochlea move and shake, sending messages to your brain that you hear a sound. And this all happens in a split second!
D
Diaphragm (DYE-uh-fram): Ever get the hiccups? Don't worry — it's just your diaphragm doing something different! This thin, dome-shaped muscle helps you breathe and separates the lungs from your stomach and intestines. When it gets irritated, the diaphragm forces the air out of your lungs in a funny way. Hic!
E
Ear Canals (KUH-nalz): You'll need a mirror to do it, but take a good look at your ear. Do you see that hole in it that goes into your head? That's an ear canal. Your ear canals let in sound so you can hear. Glands in the ear canal make cerumen, or earwax.
Eardrums: Your eardrums are a really important part of your ear. Sound waves travel through the ear canal to reach the eardrum. The eardrum is a thin flap of skin that stretches tight like a drum and vibrates when sound hits it. These vibrations move the tiny bones of the middle ear, which send vibrations to the inner ear. From the inner ear, the message is sent to the brain, which says, "Hey! I hear something!" So feel those good vibrations!
Epidermis (eh-pih-DUR-mis): Look out — your epidermis is showing! But that's OK; epidermis is the fancy name for the outermost layer of your skin.
F
Frenulum (FREN-yuh-lum): The frenulum is the piece of skin that attaches your tongue to the bottom of your mouth. But if your frenulum is too short, that's called tongue-tied, and it can cause problems with your speech. Doctors sometimes do an operation to free up the tongue by snipping the frenulum. If you need this operation, a doctor will give you a special medicine called anesthesia to keep you comfortable.
G
Genes (JEENZ): These aren't the blue pants in your drawer. These genes hang out all lined up on thread-like things called chromosomes. Genes are made up of segments of DNA and they determine physical traits, including the color of your eyes and whether your hair is straight or curly. You inherited your genes from your parents, which is why someone might say you have your mother's smile.
Genetics (juh-NEH-tiks): "Genetics" refers to the study of how physical traits and characteristics pass from one generation to the next. This is also called heredity. Genetics includes the study of genes, which have a special code called DNA that determines what you will look like and whether you are more likely to have some kinds of illnesses.
Glucose Level: Your blood glucose level (or blood sugar level) is the amount of glucose in your blood. The body gets glucose, a sugar, from the food we eat. Glucose is carried through the bloodstream to all the cells in the body. Like gas for a car, glucose is fuel for the body's cells and gives them energy.
Gluteus Maximus (GLOO-tee-us MAK-suh-mus): You don't have to look too far for this body part — you're sitting on it! This is the fancy name for the muscles of your rear end.
H
Heredity (huh-REH-deh-tee): If people say you look like your parents, they're probably talking about heredity. Maybe you've noticed that you have the same color eyes as your mom or you're tall like your dad. Your parents pass these physical traits to you through your genes.
Hormones: Hormones are special chemicals your body makes to help it do certain things — like grow up! Hormones are important when you start to go through puberty, which is when you begin developing into an adult. During this time, you're loaded with hormones that tell your body that it's time to start changing.
Insulin is an important hormone. It regulates the amount of sugar in your blood. That sugar, called glucose, is the body's main source of fuel.
I
Immune System (ih-MYOON SIS-tum): Your immune system, which includes white blood cells and lymph nodes, helps protect your body from disease. It has different parts, all of which work together to fight off outside invaders like germs. Every day your immune system does battle to keep you healthy and feeling your best.
Inhale (IN-hail): You're doing it now ... and now ... and now ... and now! You're breathing in, or inhaling, that is. You need to inhale air into your lungs to keep every cell in your body alive. Your lungs are kind of like balloons, and when you breathe in (inhale), they get bigger. Then when you breathe out (exhale) and let that air back out, they get smaller. That's why your chest goes up and down when you breathe.
Iris (EYE-ris): Your iris is the colored part of your eye. So if someone has brown eyes, it means that person's irises are brown. The iris is about more than looks, though. Your iris controls the size of the pupil — the black dot in the center of your eye — and how much light is let into your eye.
J
Joints: Joints are the places in your body where bones meet. You have big joints (like the ones in your hips, shoulders, and legs) and itty, bitty ones (like the ones in your hands and feet). Your knee is a joint and so are all the bendy parts of your fingers!
K
Kidneys (KID-nees): The kidneys are a pair of organs on either side of your spine, just below the ribcage. They filter waste materials out of the blood. The waste passes out of your body as pee. Kidneys make important hormones and regulate blood pressure and the levels of water, salts, and minerals in the body. Kidney damage can happen in someone who has had diabetes for many years, especially if their diabetes isn't controlled.
L
Lacrimal Glands (LAK-ruh-mul glandz): Boo hoo hoo, crying is what these parts help you do! These tiny glands above the outer corner of each eye turn on the waterworks and make tears.
Larynx (LAIR-inks): If you can sing "la la la," then you have a larynx! It's the fancy word for the voice box, which works with air from your lungs to let you talk, whisper, sing, and yell. Thanks, larynx!
Lens (lenz): The lens is the part of the eye that focuses on what you see. Even though you can't feel it, the lens moves and changes, depending on what you're looking at. When you look at a boat way out in the ocean, the lens gets thinner, and when you look at a page in a book, the lens gets thicker.
Ligaments (LIH-geh-mints): Like to throw, catch, dance, or play soccer? You can thank your ligaments for making it happen. Ligaments are tough bands of tissue that hold your bones together at your joints, like your elbow. They make it possible for you to bend and move in all the right ways.
Lunula (LOON-yuh-luh): Take a look at your thumb and you'll see this: It's the light half-moon shape at the very bottom of your nail. Every nail has a lunula, but it's easiest to see them on thumbnails.
Lymph (limf): Lymph is a clear fluid that flows through its own vessels located throughout the body. Lymph contains white blood cells, which are the germ fighters of the immune system.
Lymph Nodes (limf nodes): Your wonderful lymph nodes! Lymph nodes are little round or bean-shaped bumps that you usually can't feel unless they become swollen. Lymph nodes are like filters that remove germs that could harm you. They contain lymphocytes, which are special cells that fight infection. Sometimes, germs can cause some of the lymph nodes to swell, so you might feel your swollen lymph nodes on your neck when you have a sore throat. But don't worry — swollen lumps usually just mean your body is cleaning up its act!
P
Platelets (PLAYT-lits): Your blood contains many tiny cells called platelets. They help your blood clot, which means that if you get a cut, some of your platelets stick together to plug the hole in the blood vessel wall caused by the cut. Eventually, the clot dries out to form a scab to protect the healing skin underneath.
Puberty (PYOO-ber-tee): Everyone goes through puberty, even though it sometimes feels like you're the only one! It's that period of time when your body changes and matures, turning you from a kid into an adult. Although everyone is different, puberty usually starts between age 8 and 13 for girls and age 9 and 15 for boys.
Pulmonary (POL-meh-nair-ee): Breathe in ... breathe out ... and feel your pulmonary power! Pulmonary is a fancy word that means having to do with the lungs.
Pulse: Your beating heart creates a pulse. Your heart has to push so much blood through your body that you can feel a little thump in your arteries each time the heart beats! Wow! The most common places to feel a pulse is on your wrist and your neck. So try to find your pulse and feel the beat!
R
REM: REM is short for rapid eye movement, the stage of sleep when your eyes move back and forth under your closed eyelids and you have dreams.
S
Saliva (suh-LIE-vuh): Slimy! Slippery! Saliva is none other than spit, the clear liquid in your mouth that's made of water and other chemicals. Saliva helps keep the mouth moist and contains an enzyme that starts to break down food even before it hits your stomach!
Sclera (SKLAIR-uh): The sclera is the white part of your eye. It's a tough, protective covering and the muscles that control eye movement are connected to it.
Snot: Snot is that sticky, slimy stuff inside your nose. You also might hear it called mucus (say: MYOO-kus). Snot does a great job of keeping all the germs, dirt, pollen, and other stuff in the air from getting into your lungs. Talk about breathing easy!
Sphenopalatine ganglioneuralgia (SFEE-noh-pal-uh-teen gan-glee-oh-new-RAL-juh): These big words are another way to say “brain freeze” or "ice cream headache." You know, the feeling you get when you eat something really cold and your head goes "Yow!"
T
Taste Buds: If you love ice cream, thank your taste buds. Without them, you couldn't savor that satisfying sweet treat — or anything else. Tiny bumps all over your tongue called papillae (say: puh-PILL-ee) contain taste buds, which have very sensitive microscopic hairs called microvilli (say: my-kro-VIH-ly). Those tiny hairs send messages to the brain about how something tastes, so you know if it's sweet, sour, bitter, or salty.
Tendons (TEN-dunz): For keeping things together, tendons come in handy! These special cords made of tough tissue attach your body's muscles to your bones.
Trachea (TRAY-kee-uh): Your trachea is also called your windpipe. It carries air in and out of your lungs.
Tragus (TRAY-gus): That little bump on the outside of your ear canal is called the tragus. It's made of cartilage, and the funny thing is, it doesn't really do anything! But it does make it easy to tell if you have swimmer's ear because if you do, your ear will hurt when you touch your tragus.
U
Umbilical Cord (um-BIL-ih-kul kord): This is the name for the long tube that runs between a mother and her unborn baby. It carries oxygen and nutrients to the baby and waste away from the baby. When the baby is born, the doctor cuts the umbilical cord and a small piece is left attached to the baby. When this piece falls off, you can see the baby's belly button!
Urine (YOOR-in): The kidneys remove waste from the blood and make urine, also called pee. Urine is mostly water, so if you don't take in a lot of fluids (or if you sweat a lot), your urine has less water in it and it looks darker. If you drink lots of fluids, the extra fluid comes out in your pee, which looks lighter. Urine is stored in the bladder until it's peed out.
V
Veins and Arteries (vayns, AR-tuh-reez): 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 blood away from the heart. Veins, which usually look blue, return blood to the heart.
Vertebrae (VER-tuh-bray): Reach around and feel those bumps in the center of your back. Each bump is a bone called a vertebra (say: VER-tuh-brah) and there are 33 vertebrae that make up your spine. Without your vertebrae, you couldn't stand tall!
W
Wisdom Teeth (WIZ-dum): You will have learned a lot by the time you get your wisdom teeth, but they don't make you any smarter! Between the ages of 17 and 21, most people get 4 more molars all the way in the back of the mouth, one in each corner. If wisdom teeth don't grow in properly, they may have to be removed.
Y
Yawn: Yawning is when you stretch your mouth open wide. No one really knows why we do it, but it seems to be contagious. If you yawn in class, you'll probably notice a few other people will start yawning too. Even thinking about yawning can get you yawning. Even though we yawn when we're tired or bored, we hope you didn't yawn while reading about yawning!
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
© 1995- The Nemours Foundation. KidsHealth® is a registered trademark of The Nemours Foundation. All rights reserved.
Images sourced by The Nemours Foundation and Getty Images.
