DORA: What is spit?
WENDELL: You know, Dora, I'm partial to slime. Your body doesn't have as much slime as, say, a slug... but human saliva's still pretty great....
DORA: Are you talking about spit?
WENDELL: Yup. Spit, saliva, whatever you call it, is glorious slime!

DORA: So where does spit come from?
WENDELL: Ah, good question! Hidden in your mouth, you have special structures called salivary glands that spew spit. In fact, they shoot out about 2 pints of saliva each and every day. Now that's a heck of a lot of spit -- about one quarter of the amount of blood you have in your whole body!

DORA: What's spit made of?
WENDELL: 99% water! Add a small amount of chemicals, mucin, to make it slimey, lysozyme to destory bacteria, and salivary amylaze to begin breaking down food. I hate to say this but there are also small amounts of the waste products -- urea and uric acid. Know where else you find these? In sweat and, you guessed it, urine or pee. But don't worry. It's all perfectly natural!
DORA: But it sure is yucky!

DORA: What's spit good for, anyway?
WENDELL: What isn't it good for, you mean. You probably couldn't eat without spit. Food would stay in some kind of hard lump in your gullet. If the mushed lump weren't moistened, you couldn't swallow it. Your mouth wouldn't water in preparation when you look or think about something delicious. And, meanwhile, you wouldn't have enzymes in saliva to help digest starches -- like bread and spaghetti -- so your body can use them. And, most importantly you probably wouldn't be able to taste anything.

DORA: What's spit got to do with taste?
WENDELL: Your tongue has thousands of taste buds or cells which are sensitive to the different chemicals from food that have been dissolved by your saliva. It's those chemicals which are going to make you think -- how salty, or sour, or sweet, or bitter. See, I told you, spit was glorious!
DORA: You were right, Wendell. Spit is cool!