Question

Observe the schematic diagram that depicts a small section of nucleic acid. The bases in two strands are paired through hydrogen bonds that are shown by the dark lines. Identify the correct sequence of nucleotide in the 5’-3’ direction.

Options

• GCAT

• CGTA

• TAGC

• ATCG

Answer 1

CGTA

Explanation:

• The image shows a DNA double-helix segment with complementary base pairing.

• Adenine (A) pairs with Thymine (T), and Guanine (G) pairs with Cytosine (C) through hydrogen bonds.

• The strands are antiparallel, meaning one runs 5’ → 3’ while the other runs 3’ → 5’.

• Observing the 5’-3’ direction, the correct nucleotide sequence is GCAT.