How many atoms are in a cell?

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Thu Sep 18 02:54:42 EST 1997

In article <341C91A6.712FEE42 at>, Andrew Ippolito <aji97 at> wrote:
>    Sorry to ramble, but the answer to your question is probably on the
>order of
>10^11 or so atoms.  (that's a quatrillion or something like that:)
>Irina Gayevskaya wrote:
>> I was wondering, how many ATOMS are there in the simplest unicellular
>> organism (excluding bacteria - those that have nucleus)?
>> Please specify if the number is your guess or from a reliable source
>> and state the source
>>                                         Thanks, Tom

More like 10^14
Assuming the cell being just a tiny drop of water (after all its mostly that):
cell volume in the range of 10^-9 ml
water MW=18g/mol
Avogadro's number=6x10^23 pieces/mol
you get:
the number of moles of water in the cell: 10^-9/18 moles/cell
the number of water molecules in the cell: (10^-9x6x10^23)/18 molecules/cell=
(10^14)/3 molecules/cell
and as each water molecule has 3 atoms:
the number of atoms per cell: 3x(10^14)/3=10^14 atoms/cell


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