Biology mitotic division

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ayapapaya
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Hey,

can someone help with this:
In humans, after the gametes join at fertilisation, every cell of the developing embryo undergoes mitotic divisions before the embryo attaches to the uterus lining.
•   The first cell division takes 24 hours.
•   The subsequent divisions each take 8 hours.
After 3 days, the embryo has a total volume of 4.2 × 10−3 mm3.
What is the mean volume of each cell after 3 days? Express your answer in standard form.
Show your working.

Thanks in advance
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Jpw1097
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Report 3 months ago
#2
(Original post by ayapapaya)
Hey,

can someone help with this:
In humans, after the gametes join at fertilisation, every cell of the developing embryo undergoes mitotic divisions before the embryo attaches to the uterus lining.
•   The first cell division takes 24 hours.
•   The subsequent divisions each take 8 hours.
After 3 days, the embryo has a total volume of 4.2 × 10−3 mm3.
What is the mean volume of each cell after 3 days? Express your answer in standard form.
Show your working.

Thanks in advance
OK, so to work out the mean volume of each cell, you need to divide the total volume of the embryo (which you already have) by the number of cells after 3 days.
The first cell division takes 24 hours, so after 24 h you have 2 cells. Subsequent divisions take 8 hours, so after 32 hours there will be 4 cells, after 40 hours there will be 8 cells, after 48 h you will have 16 cells, and so on... So how many cells will have after a total of 72 hours?
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