DORA: Oh my! My armpits...I think they smell. How come, Wendell?
WENDELL: It's sweat, my dear! Isn't it swell?

DORA: Huh, you're kidding, right?
WENDELL: No, truly. Sweat is great natural air conditioning! Be glad you're not a dog! They sweat through their tongue and pant to cool off! You ooze sweat -- the water, salts, urea (the same chemical that's in urine), ammonia, sugar and other chemicals -- out of tiny holes in your skin. And as the sweat evaporates, you feel cooler.

DORA: But why does sweat smell?
WENDELL: Dora, you sweat all over your body -- and most of it doesn't smell at all! The sweat doesn't smell, it's the bacteria, the microbes, munching on the sweat that give off those odors!

DORA: Is that what's happening in my pits?
WENDELL: Yes, but your armpit sweat comes from a different kind of sweat gland. It makes a thicker and stinkier sweat which contains a whole symphony of scents with a variety of purposes.

DORA: Like what?
WENDELL: In animals, these scents are called pheromones. They attract animals to each other like a male rat to a female rat or help an ant recognize other ants from its nest.

DORA: But what purpose do they serve in humans?
WENDELL: That's a very good question. Scientists are less clear what, if any, real purpose these scents have in humans. But they do make the sweat under your arms somewhat odoriferous!

DORA: But what about bacteria?
WENDELL: If you don't bathe often enough, the bacteria have a chance to gather in your pits and make a feast out of old dead skin cells and sweat. And, boy, sometimes they can make a stink!

DORA: But sweat under my arms didn't always smell. Why now?
WENDELL: You'll be excited to know that the glands that make underarm sweat only started to work as you entered puberty. Congratulations!

DORA: What's puberty?
WENDELL: It's the range of years when your body matures from that of a child to an adult . During this time you'll experience a whole variety of big and small changes.

DORA: Like what?
WENDELL: Your body's shape changes; hair develops in brand new place. Boy's chins begin to sprout hair. Girls begin to develop breasts and make internal and external changes that will eventually enable you to have children. So, you may find yourself with pimples; and you develop things like a new kind of sweat under your arms!

DORA: What causes my body to go through puberty?
WENDELL: Hormones, my dear Dora, hormones!

DORA: What are they?
WENDELL: Hormones are chemicals made by special glands in your body. And they do such incredibly important things that this collection of glands has been given a name - the endocrine system. These chemicals stimulate, regulate and coordinate all sorts of important activities in your body including how and when you go through puberty.

DORA: So it's hormones I have to thank for smelly pits?
WENDELL: Yup! But, look, there's nothing wrong with a little body odor. Now you may want to bathe a little more often to keep those bacteria from feasting. And, if you want, you can use a deodorant to cut down on the amount of sweat you produce. But, everybody sweats at least a little.

DORA: Thanks, Wendell.
WENDELL: Anytime, Dora!