Q: Why do you get little bags under your eyes when you don't get enough sleep?

-Sophie P., age 10.5, TX

A: Jet-lagged travelers often joke about the bags under their eyes being large enough to be checked by airport security. However, the connection between lack of sleep and excess undereye baggage is not scientifically established.

It seems that the size of those puffy sacks says a lot about your genetic heritage, and maybe not so much about how you spent the last twenty-four hours. "Skin laxity and fat deposits under the skin are hereditary traits," says Dr. Kucy Pon* from the University of Toronto. Some people simply have looser skin around the eyes.

Temporarily puffy eyes, however, can come from sinus congestion-from a cold or an allergic reaction. And eyes may get even puffier with sleep. According to Dr. Pon, "When you are sleeping, more fluid accumulates in your face."

So much for "beauty sleep"!

-Andy

*Dr. Kucy Pon is Assistant Professor in the Division of Dermatology at the University of Toronto.

Q: Why does soda fizz when you pour it over ice?

-Kathleen G., age 14, Ontario, Canada

A: Soda gets its bubbly personality from a turbo-charge of carbon dioxide. "Carbonated drinks are super-saturated," explains biochemist Karl Siebert.* "They have more carbon dioxide than can actually stay dissolved in the liquid."

While the soda is sitting undisturbed in a can, strong bonds between the water molecules in the liquid hold the bubbles of carbon dioxide gas in place, making it hard for bubbles to expand or new ones to form.

However, once the liquid touches the ice in your glass, the soda positively parties, erupting with a foamy display. Solid surfaces, particularly the jagged contours of the ice cubes, help to break the surface tension that holds the water molecules together. Each crevice and pore on the ice is like "Party Central" for the carbon dioxide-a perfect site for bubbles to gather and grow. That's why, if you pour too quickly, your soda might go "over the top" with its fizzy enthusiasm.

-Ruth

*Karl Siebert is a professor of biochemistry at the Food Science and Technology Department of Cornell University in New York.

© 2008 Carus Publishing Company Provided by ProQuest LLC. All Rights Reserved.