Home › AP Biology › Biology › DNA Structure and Function › How many hydrogen bonds hold a cytosine and guan…
How many hydrogen bonds hold a cytosine and guanine pair together?
ATwo bonds
BThree bonds
CFour bonds
DOne bond
Answer & Solution
Correct answer: B. Three bonds
1. The two kinds of base pair are held with different strength.
2. Adenine and thymine form two hydrogen bonds.
3. Cytosine and guanine form three hydrogen bonds.
4. Three is therefore the stronger of the two pairings.
_Source: OpenStax Biology for AP(R) Courses (CC BY 4.0), Ch 14 'DNA Structure and Function', sections 14.1-14.6_
Related questions
A limitation of Sanger's original sequencing method is that it can read:Rosalind Franklin did not share the Nobel Prize for the DNA structure because:The phosphodiester bond of the DNA backbone joins which two carbons?How many base pairs are there in one complete turn of the DNA helix?Each base pair sits how far from the next along the helix?Purines differ from pyrimidines structurally because purines have:The two strands of a DNA double helix are antiparallel, meaning one runs 5' to 3' and the In the Hershey and Chase centrifugation, the heavier bacterial cells ended up in the: