How many cells do you have?
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   The  average  eukaryotic  cell is about 100 µm (100 x 10^-6 m. = 10^-4
   m.) long.
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   You have 200 trillion (2 x 10^14) somatic cells (p. 230).
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   Total  length  of your cells lined up end-to-end: (2 x 10^14) x (10^-4
   m.) = 2 x 10^10 m. = 2 x 10^7 km.
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   The earth's circumference is 40 million m. (40 x 10^6 m. = 4 x 10^7 m.
   = 4 x 10^4 km.
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   2  x  10^7  km.  /  4 x 10^4 km. = 500: your cells can wrap around the
   earth 500 times.
Updated Apr 01, 2011 by Peter Chen
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