Question

How many nitrogen bases can each turn of DNA accommodate? How many nitrogen bases can each turn of DNA accommodate? @Biology

Answer 1

It would be two, if by turn you mean rung. the nitrogen bases come in pairs, AT and GC

Answer 2

thanks a lot

Answer 3

you're welcome! :D

Answer 4

for future reference, it's actually nitrogenous, ( I think) when you use it as an adjective.

Answer 5

What cathyangs said is correct, each base pair has one nitrogenous base (and a phosphate group) meaning each "rung" of the "ladder" has 2 nitrogenous bases... But when I read your question, I thought more in lines of the number of pairs per turn of the helix, given usually as: \[n_{b}\]
It is important to note when asking that question, that there are 3 types of DNA (A,B, and Z)
they all have their differences, and in this case... on average:
A-DNA: 11 base pairs per turn
B-DNA: 10 base pairs per turn
Z-DNA: 12 base pairs (6 dimers) per turn

B-DNA is the 'normal' structure that was first presented by Watson and Crick.

Answer 6

I'd like to add that 1 base pair has 2 nitrogenous bases, so to make that list in the form that you asked for it:
A-DNA: 22 nitrogenous bases per turn
B-DNA: 20 nitrogenous bases per turn
Z-DNA: 24 nitrogenous bases per turn