## E. coli numbers

About microscopic forms of life, including Bacteria, Archea, protozoans, algae and fungi. Topics relating to viruses, viroids and prions also belong here.

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pfdunlop
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### E. coli numbers

Hi, I am studying rDNA for an exam and am probably procrastinating (but not really as I am looking at insulin production in E. coli).
If you start off with one cell, and it divides every 30 minutes, how many will u have after 24 hours.
I thought 1 - becomes 2, then 2 doubles every 30 minutes (48 times in 24 hours minus the first time, so 47). So it would just be 2^47 = 140737488355328 or 1.4 x 10^14. Is that right? I know its going to be a lot of cells, but this many.
Just for my own interest,

Cheers

MrMistery
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that seems right to me.
"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

pfdunlop
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Hey cheers. Procrastination over. For now anyway.
Thanks

mayoorraj
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this is very interesting n there is a simple logic here,the cells dividing at the rate u mentioned will reach thousand times the weight of earth in 24 hrs which actually will not happen n not possible too , and such a growth takes place only during exponantial phase of growth as soon as nutrients become limiting the cells will enter into stationary phase thats y bacterial growth curve r sigmoid. So here u will not get the no of cells u hav calculated

Homeostasis
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### Re:

mayoorraj wrote:this is very interesting n there is a simple logic here,the cells dividing at the rate u mentioned will reach thousand times the weight of earth in 24 hrs which actually will not happen n not possible too , and such a growth takes place only during exponantial phase of growth as soon as nutrients become limiting the cells will enter into stationary phase thats y bacterial growth curve r sigmoid. So here u will not get the no of cells u hav calculated

you are just being lazy.
you would have to double 48 times
10=512
20=524288
30=536870912
40=549755813888
48=140737488355328 <<< final

unless you are supposed to square it each time.... then I would need a more powerful brain

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