Question

If nucleotide sequence on one strand is given, the nucleotides on the other strand can be found out because of

• A. Complementary base pairing property
• B. Antiparallel nature
• C. Hydrogen bond formations between two strands
• D. Phosphodiester bond

Hint:

Complementary base pairing is the physical basis for the semi-conservative replication of DNA, ensuring genetic information is copied with high fidelity.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
The double-helical structure of DNA consists of two polynucleotide chains running in opposite directions, held together by chemical interactions between their nitrogenous bases.

Step 2: Detailed Explanation:
The key to understanding DNA replication, transcription, and sequencing lies in the base-pairing rules discovered by Erwin Chargaff and modeled by Watson and Crick.
According to these rules:
- Adenine (A), a purine, always pairs specifically with the pyrimidine Thymine (T) via two hydrogen bonds.
- Guanine (G), a purine, always pairs specifically with the pyrimidine Cytosine (C) via three hydrogen bonds.
This highly specific pairing is known as complementary base pairing.
Because of this property, the sequence of nucleotides on one strand dictates the exact sequence on the opposite strand.
If one strand has the sequence 5'-ATCG-3', the opposite strand must have the complementary sequence 3'-TAGC-5'.

Step 3: Final Answer:
The opposite strand sequence can be determined because of the Complementary base pairing property.