Question
Biology Question on the molecular basis of inheritance
If the length of a DNA molecule is 1.1 metres, what will be the approximate number of base pairs?
A
3.3 × 109 bp
B
6.6 × 109 bp
C
3.3 × 106 bp
D
6.6 × 106 bp
Answer
3.3 × 109 bp
Explanation
Solution
The length between two base pairs is 0.34nm.
Total length of double helix DNA = total number of base pairs * distance between two bp
Hence, total no. of base pairs = (Total length of double helix DNA) / (distance between two bp)
total no. of base pairs = 1.1m/0.34 nm
= (1.1 x 109 nm) / (0.34 nm)
= 3.235 x 109 base pairs
= 3.3 x 109 base pairs
Therefore, the correct answer is (A) : 3.3 × 109 bp.