Tasty Tidbits
Don't put that mirror away yet! Look at your tongue again, but this time look closely at the top of it. Notice how it's rough and bumpy — not like the underside, which is very smooth. That's because the top of your tongue is covered with a layer of bumps called papillae (say: puh-pih-lee).
Papillae help grip food and move it around while you chew. And they contain your taste buds, so you can taste everything from apples to zucchini! People are born with about 10,000 taste buds. But as a person ages, some of his or her taste buds die. (An old person may only have 5,000 taste buds!) That's why some foods may taste stronger to you than they do to an adult. Taste buds can detect sweet, sour, bitter, and salty flavors.
Traveling Tastes
So how do you know how something tastes? Each taste bud is made up of taste cells, which have sensitive, microscopic hairs called microvilli (say: mye-kro-vih-lye). Those tiny hairs send messages to the brain, which interprets the signals and identifies the taste for you.
Identifying tastes is your brain's way of telling you about what's going into your mouth, and in some cases, keeping you safe. Have you ever taken a drink of milk that tasted funny? When the milk hit the taste buds, they sent nerve impulses to your brain: "Milk coming in — and it tastes funny!" Once your brain unscrambled the nerve impulses, it recognized the taste as a dangerous one, and you knew not to drink the milk.
Some things can make your taste bud receptors less sensitive, like cold foods or drinks. An ice pop made from your favorite juice won't taste as sweet as plain juice. If you suck on an ice cube before you eat a food you don't like, you won't notice the bad taste.
Friend of the Tongue
Last time you had a cold and your nose felt stuffed up, did you notice that foods didn't taste as strong as they usually do? Well, that's because your tongue can't take all of the credit for tasting different flavors — it has help from your nose.
Your nose helps you taste foods by smelling them before they go in your mouth and as you chew and swallow them. Strong smells can even confuse your taste buds: Try holding an onion slice under your nose while eating an apple. What do you taste?
Your tongue also gets help from your teeth, lips, and mouth. Your teeth help your tongue grind food as the tongue mixes the food around your mouth. And without your teeth, lips, and the roof of your mouth, your tongue wouldn't be able to form sounds to make words.
Saliva is also a friend of the tongue. A dry tongue can't taste a thing, so saliva helps the tongue by keeping it wet. Saliva moistens food and helps to break it down, which makes it easier for the tongue to push the food back to swallow it.
Fighting Germs
If all that wasn't enough, your tongue even helps keep you from getting sick. The back section of your tongue contains something called the lingual tonsil (say: ling-gwul tahn-sul). Lingual is a medical word that means having to do with the tongue, and tonsils are small masses of tissue that contain cells that help filter out harmful germs that could cause an infection in the body.
But when you have tonsillitis, it's not your lingual tonsil that's infected. Tonsillitis affects the palatine (say: pah-luh-tyne)tonsils, which are two balls of tissue on either side of the tongue. The lingual tonsil, the palatine tonsils, and the adenoids are part of a bigger system that fights infections throughout your body.
The Tongue Is One Tough Worker
With all that talking, mixing food, swallowing, tasting, and germ fighting, does your tongue ever get a rest?
No. Even when you are sleeping, your tongue is busy pushing saliva into the throat to be swallowed. It's a good thing, too, or we'd be drooling all over our pillows. Keep your tongue in tip-top shape by brushing it along with your teeth and avoiding super-hot foods. A burned tongue is no fun!
