Asked in PMC Practice Test 10 (2021) 2021

How many Hydrogen bonds are there in a Cytosine-Guanine pair?

Correct answer: D. 3

  • A. 0
  • B. 1
  • C. 2
  • D. 3

Explanation

Option A: This option suggests that there are no hydrogen bonds in a Cytosine-Guanine pair. However, in reality, hydrogen bonds do exist between the C and G bases. Option B: This option implies that there is only one hydrogen bond in a Cytosine-Guanine pair. However, the actual number of hydrogen bonds in a C-G pair is three.Option C: This option proposes that there are two hydrogen bonds in a Cytosine-Guanine pair. However, the correct number of hydrogen bonds in a C-G pair is three. Option D: Hydrogen bonds form between the complementary bases in DNA. In the C-G pair, Cytosine forms three hydrogen bonds with Guanine (G), establishing a stable base pairing. The three hydrogen bonds provide significant strength to the DNA double helix structure.

Written and checked by , contributorLast updated
Report an error

The more specific you are, the faster it gets fixed. A source beats an opinion.

Prefer email? [email protected]

About Structure of DNA

DNA structure includes nucleotides made of deoxyribose, phosphate and nitrogenous bases, arranged in two antiparallel polynucleotide strands. Questions cover the double helix, phosphodiester and hydrogen bonds, complementary base pairing between adenine and thymine and between guanine and cytosine, and the significance of major and minor grooves.

Practise Biological Molecules

1,790 free Biological Molecules MCQs from Biology, each with the correct answer and an explanation. Unlimited attempts, no account needed.

Discussion

Stuck on an option, or know a faster way to get there? Ask or explain it here.

No comments yet. Be the first to explain this one.

Exams that ask Biology questions like this

Biology is on 8 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.

More Structure of DNA questions