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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).

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Vaccines prevent between 2.5 and 4 million deaths every year.

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The first documented use of surgical anesthesia in the United States was in Connecticut in 1844.

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Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.

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Congestive heart failure is a serious disorder that carries a reduced life expectancy. Heart failure is usually a chronic illness, and it may worsen with infection or other physical stressors.

Left: This web was woven by a 17-day-old spider, showing regular patterns. Right: This web was woven Left: This web was woven by a 17-day-old spider, showing regular patterns. Right: This web was woven
Spider Exoskeleton Spider Exoskeleton
Spider Spider
The upper intake manifold, often called a plenum, attaches to the lower intake manifold. The upper intake manifold, often called a plenum, attaches to the lower intake manifold.
The cell membrane is a lipid bilayer with signal proteins and channel proteins embedded in it. The cell membrane is a lipid bilayer with signal proteins and channel proteins embedded in it.
Illustration of the cell membrane Illustration of the cell membrane
Video: Cell mediated immune response to a viral infection Animation

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