Page 86 - Girl's World (October 2019)

your science scoop
IS SUGAR REALLY SO BAD
TRICKY You’ve probably been warned that eating
FOR MY TEETH?

— Gwenny, 8, AZ
SCIENCE

QUESTIONS sugary sweets will “rot your teeth,” but it

turns out that sugar itself isn’t the real
culprit behind tooth decay. Cavities are

formed when bacteria in the mouth digest

debris left on your teeth after you eat. Such

debris might come from sugar-filled snacks
like cookies and candy, but they can also

come from healthy foods like whole grains,

vegetables and fruits. If you don’t brush

your teeth after eating, bacteria in your
mouth will produce an acid that combines

the debris with saliva to form plaque. It’s

actually this plaque — not sugar — that

GW gives you the lowdown on some of the rots your teeth. So as long as you brush
your teeth after eating a sugary treat, your
world’s most mind-boggling mysteries!
teeth should stay healthy!

WHY CAN’T ASTRONAUTS

BREATHE IN SPACE?
HOW COME SOME PEOPLE
— Jane, 10, FL
SNORT WHEN THEY LAUGH?

— Bibi, 11, NC
On Earth, humans live in the troposphere where
Laugh-snorting occurs when air is exhaled through
the air is thick and breathable. But air gets thinner
the nose instead of through the mouth. It’s kind
and thinner the higher up you go, and by the time
of like snoring: When air is restricted in your nose
astronauts break through the atmosphere and reach
or your throat, it creates something called “airflow
space, the air becomes so thin that they aren’t able
turbulence.” As air quickly moves in or out, it causes
to breathe. But thankfully, scientists and engineers
vibrations in the surrounding tissues that result
have figured out a way for astronauts to “breathe”
in the snorting sound! Opening your mouth
in space: Water is brought up to the International
whenever you laugh is one way to redirect the
Space Station and then split into oxygen and
air and prevent snorting, but consciously
hydrogen. The oxygen from the water is then vented
changing a laugh is harder than it might
into the space cabin for astronauts to breathe in,
seem. So remember: People who snort
while the unbreathable hydrogen is vented out!
when they laugh probably can’t help
it — and they don’t need to!
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