Question

Base pairs present in one turn of DNA are

• A. $12$
• B. $11$
• C. $10$
• D. $9$

Answer 1

The correct option is C $10$

DNA has the double helical structure where the two strands are tightly coiled over each other. B- DNA has right-handed helix with the major and minor groove. The diameter of the DNA is 20 A${}^o$. The distance between base pairs is 3.4 A${}^o$. The total length of one turn of DNA is 34 A${}^o$. The total number of the base pair in each turn is 34/3.4 = 10.

So, the correct answer is option C.