Question

Length of DNA with 23 base pairs is ______.

Options

• 78.4 Å

• 78.2 Å

• 78 Å

• 74.8 Å.

Answer 1

78.2 Å

Explanation:

In the standard B-DNA model, the distance between two adjacent base pairs is approximately 3.4 Å (Angstroms). To find the total length of a DNA segment, you simply multiply the number of base pairs by this distance. Therefore, for a DNA molecule with 23 base pairs, the calculation is 23 × 3.4 Å, which equals 78.2 Å. This constant spacing is a fundamental characteristic of the double helix structure discovered by Watson and Crick, ensuring the molecule maintains a stable and uniform shape.