Q. Purines possess nitrogen at :

Q. Purines possess nitrogen at :

1. 1, 2, 4 and 6 position
2. 1, 3, 5 and 7 position
3. 1, 3, 7, and 9 position
4. 1, 2, 6 and 8 position

Solution :

Correct option : C There are two types of nitrogenous bases in the nucleotides – Purines and Pyrimidines. Purines are 9 membered double ringed nitrogen bases which possess nitrogen at 1,3,7 and 9 position, e.g., adenine and guanine. Pyrimidines are six membered nitrogen bases that contain nitrogen at 1 and 3 position, e.g., cytosine, thymine and uracil.