Question

Length of DNA with 23 base pairs is

• A. 78.4 A${}^o$
• B. 78.2 A${}^o$
• C. 78 A${}^o$
• D. 74.8 A${}^o$

Answer 1

The correct option is D 74.8 A${}^o$

In the dsDNA molecule, the distance between base pairs is 3.4 ${}^0$A. So the distance between first and second base pair will be 3.4 ${}^0$A. Distance between first and third base pair will be 3.4 * (n-1) ${}^0$A, where n is the number of base pairs, i.e., 3.4 * 2 = 6.8 ${}^0$A.

Similarly, the distance between 23 base pairs will be 3.4 * 22 = 74. 8 ${}^0$A.

Thus, the correct answer is option D.