Question

A particular gene measures about 1 µm in length along a double-stranded DNA molecule. What is the approximate number of base pairs in this gene?

Options

• 3000

• 300

• 30

• 3

Answer 1

3000

Explanation:

 1 µm = 1000 nm,

B-form DNA adjacent base pairs are spaced ≈ 0.34 nm apart,

So, the number of base pairs = `(1000 nm)/(0.34 nm)`

= 2941

= 3.0 × 10³

= 3000