How could a molecule that is more that a yard long, with some 300 million twists, fold into a short, thick chromatid? Explain how this indeed possible. Any help is appreciated.
2007-03-25 13:54:12 · 3 answers · asked by tubascuba 1 in Science & Mathematics ➔ Biology
the dna in each chromosome is thought to be a single molecule, and humans have 46 chromosomes, among which those approximately 6 billion base pairs are distributed. while it may be long compared to a cell, it is extremely thin -- 2x10^-9 m across. in three dimensions, this translates to around pi * (1x10^-9 m)^2 * 6 m ~= 2x10^-17 m^3 = 2x10^-11 cubic centimeters.
2007-03-25 14:07:02 · answer #1 · answered by clark 3 · 0⤊ 0⤋
DNA isn't a single molecule, so it might be a little bit of a trick question. It simply coils and twists into an incredibly compact structure.
2007-03-25 20:58:45 · answer #2 · answered by ritifo 2 · 0⤊ 0⤋
You can read about this process, but I think it's informative to watch an animation of the wrapping process. Try this one:
http://www.wehi.edu.au/education/wehi-tv/dna/wrapping.html
2007-03-25 21:12:35 · answer #3 · answered by ecolink 7 · 0⤊ 0⤋