Question
Biology Question on the molecular basis of inheritance
In the double-helical structure of DNA, the pitch of the helix is
A
3.4 nm
B
0.34 nm
C
6.6 nm
D
34 nm
Answer
3.4 nm
Explanation
Solution
In B-DNA, one turn of the spiral has about 10 nucleotides on each strand of DNA. It occupies a distance of about 3.4 nm (34?) so that adjacent nucleotides or their bases are separated by a space of about 0.34 nm (3.4 ?).