# Biology

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#1
Does anyone know how to answer this question..
The length of a DNA double helix increases by 0.34 nm for every pair of nucleotides.
The total number of nucleotides in a human body cell is 1.2 × 10^10.
Calculate the total length of double helix in a human body cell.
0
1 month ago
#2
Is it not as simple as translating one nucleotide (0.34nm) into metres (3.4x10^-10 m) then multiplying that by the number of nucleotides in the single cell divided by 2 (1.2x10^10 / 2) to get the total length?

Ball park: 2 metres, but I'll let you do the maths for the exact answer because otherwise its cheating! I think the general consensus is between 2 and 3 metres, but that's probably more exact than the level of the question needs.
Last edited by siarc; 4 weeks ago
1
#3
I thought it was that simple siarc but thought I could have done it wrong because the question was worth 5 marks! thanks for the help
1
1 month ago
#4
(Original post by Elisabeth3210)
Does anyone know how to answer this question..
The length of a DNA double helix increases by 0.34 nm for every pair of nucleotides.
The total number of nucleotides in a human body cell is 1.2 × 10^10.
Calculate the total length of double helix in a human body cell.
Did you ever get an answer to this? I was thinking 0.34 x 1.2 x 10(to power of 10)/2 = 2040000000 then convert to metres but not sure if that is right - the answer should be somewhere between 2-3 metres so in right area (just) - could you let me know if you think this is right or someone gave you the right answer - thanks
0
4 weeks ago
#5
(Original post by JB120X)
Did you ever get an answer to this? I was thinking 0.34 x 1.2 x 10(to power of 10)/2 = 2040000000 then convert to metres but not sure if that is right - the answer should be somewhere between 2-3 metres so in right area (just) - could you let me know if you think this is right or someone gave you the right answer - thanks
Dont forget to divide the total number of nucleotides by 2 as they come in pairs when multiplying for length.
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