JEE Main levelSingle correct optionDifficulty 2 of 3bm212
Assertion (A): RNA is hydrolysed readily by dilute alkali, whereas DNA is stable under the same conditions.
Reason (R): Ribose in RNA has a 2-prime hydroxyl group next to the phosphodiester linkage, whereas 2-deoxyribose in DNA does not.
ABoth A and R are true, and R is the correct explanation of A
BBoth A and R are true, but R is not the correct explanation of A
CA is true but R is false
DA is false but R is true
Answer: A
The 2-prime OH of RNA attacks the adjacent phosphorus to cleave the chain. DNA has no 2-prime OH, so it resists this path. Both statements are true and R explains A.