Question

What is the typical distance between two base pairs in nm?

(a) 0.34 nm

(b) 0.32 nm

(c) 0.33 nm

(d) 0.35 nm

This question was posed to me in examination.

This intriguing question originated from Packaging of DNA Helix in division Molecular Basis of Inheritance of Biology – Class 12

Answer 1

Right answer is (a) 0.34 nm

The explanation: The double stranded helical structure of the DNA, takes a turn after every 10 base pairs which is noted to be as 3.4 nm. This is called as a pitch (distance). 0.34 nm is considered to be the distance between 2 base pairs.