Question

a ds dna fragment 204 angstrum length has 140 hydrogen bonds how many adenine are ther

Answer 1

Explanation:

In three turns there will be 30 base pairs of DNA or 60 nucleotides. So, 12 nucleotides are thymine. thymine is double bonded with hydrogen bonds with adenine so 12 nucleotides are adenine according to Chargaff's rule. So it will have 24 hydrogen bonds.

Answer 2

Answer:20 adenine

Explanation:3.4Ä is the distance between each basepairs

• no of base pairs 204÷3.4≈60
• no of h bonds ≈140
• therefore 40 double bonds and 20 triple bonds are there
• hence there is 20 adenine in those double bond