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Below are 10 random bionumbers. Click a row for more details
ID Property Organism Value Range Units
101735 number of perspiratory glands Human Homo sapiens 1.8e+6 glands
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101860 peak intracellular concentration of acetate in respiratory phase Budding yeast Saccharomyces cerevisiae ~30 mM
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100031 Spacing between ions Bacteria Escherichia coli 2.1 nm/molecule
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100063 Number of chromosomes/cell Bacteria Escherichia coli 2.3 Unitless
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102019 Beta-galactosidase tetramers per induced cell Bacteria Escherichia coli 10000 unitless
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100813 Average chlorophyl content concentration in the world oceans euphotic zone Biosphere 0.32 mg/m^3
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100711 Weight of skin Human Homo sapiens 4.1 kg
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100930 mitochondria volume share in the cell Cod 1-25 Percent
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101937 Percent of cell that is DNA by dry weight Bacteria Escherichia coli 3.1 %
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101590 Virus production rate Influenza ~10-100 1/hour
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BioNumbers - the numbers you need, with references, in under a minute.

In August 2008, twenty highly motivated Harvard graduate students and post-docs were given the QBioChallenge - a set of six basic questions in quantitative biology.

For example: How many mRNAs are in a yeast cell? (a)~10,000 (b)~100,000 (c)~1,000,000 or (d)~10,000,000

After an hour of searching the internet and Harvard's collection of electronic journals, they got fewer than half of the questions right. Following this frustrating effort they were given a tip: use bioNumbers (www.bioNumbers.org). Using bioNumbers they found the answers to most questions and had full references within 10 minutes. In a few more minutes they became registered users and added entries to the bioNumbers database themselves.

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