Question

if a 50-base-pair stretch of dna is 15% thymine (t) & 15% adenine (a)then how many hydrogen bonds should hold the two strands together in this stretch of dna?

Answer 1

The total number of hydrogen bonds in this 50-base pair DNA stretch, considering that 15% is adenine and the same amount is thymine, would be 134.

Step-by-step explanation:

In a DNA molecule, adenine (A) pairs with thymine (T) through two hydrogen bonds, and guanine (G) pairs with cytosine (C) through three hydrogen bonds. In this 50-base pair stretch of DNA, 15% is adenine, which is 15% of 50, or 7.5 base pairs (round to 8 for simplicity). As the same amount will be thymine, that means 16 base pairs are either adenine or thymine. The remaining 34 base pairs will be either guanine or cytosine. Therefore, the total number of hydrogen bonds would be (16 x 2) + (34 x 3) = 32+102 = 134 hydrogen bonds.

Learn more about Hydrogen Bonds in DNA