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Did you know?

Calcitonin is a naturally occurring hormone. In women who are at least 5 years beyond menopause, it slows bone loss and increases spinal bone density.

Did you know?

Stroke kills people from all ethnic backgrounds, but the people at highest risk for fatal strokes are: black men, black women, Asian men, white men, and white women.

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Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.

Did you know?

Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.

Did you know?

The modern decimal position system was the invention of the Hindus (around 800 AD), involving the placing of numerals to indicate their value (units, tens, hundreds, and so on).

Species richness increases with island size. Species richness increases with island size.
Indicator and umbrella species. Indicator and umbrella species.
Earth as viewed from Lunar orbit during the Apollo 8 mission, Christmas Eve, 1968. Africa is at the Earth as viewed from Lunar orbit during the Apollo 8 mission, Christmas Eve, 1968. Africa is at the
Outcome of myocardial infarction. Forty percent of 1-week survivors have late complications ... Outcome of myocardial infarction. Forty percent of 1-week survivors have late complications ...
Species-area curves Species-area curves
Four Butterflies, Two Species Four Butterflies, Two Species
Video: Ciliate conjugation Animation

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