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Did you know?

There can actually be a 25-hour time difference between certain locations in the world. The International Date Line passes between the islands of Samoa and American Samoa. It is not a straight line, but "zig-zags" around various island chains. Therefore, Samoa and nearby islands have one date, while American Samoa and nearby islands are one day behind. Daylight saving time is used in some islands, but not in others—further shifting the hours out of sync with natural time.

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Human kidneys will clean about 1 million gallons of blood in an average lifetime.

Did you know?

Though “Krazy Glue” or “Super Glue” has the ability to seal small wounds, it is not recommended for this purpose since it contains many substances that should not enter the body through the skin, and may be harmful.

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Vaccines prevent between 2.5 and 4 million deaths every year.

Did you know?

The Centers for Disease Control and Prevention (CDC) was originally known as the Communicable Disease Center, which was formed to fight malaria. It was originally headquartered in Atlanta, Georgia, since the Southern states faced the worst threat from malaria.

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Negative feedback loops affecting hypothalamic and anterior pituitary tropic hormones. Negative feedback loops affecting hypothalamic and anterior pituitary tropic hormones.
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The cell wall of a Gram-negative bacterium, E. coli The cell wall of a Gram-negative bacterium, E. coli
Video: Multiple Sclerosis Animation

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