Question

Assertion (A): The backbone of DNA and RNA molecules is a chain consisting of heterocyclic base, pentose sugar and phosphate group.

Reason (R): Nucleotides and nucleosides mainly differ from each other in the presence of phosphate group.

विकल्प

• Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).

• Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).

• Assertion (A) is true, but Reason (R) is false.

• Assertion (A) is false, but Reason (R) is true.

Answer 1

Assertion (A) is false, but Reason (R) is true.

Explanation:

The DNA molecule is made up of two strands that spiral around each other like a twisted ladder. Each strand has an alternate backbone of sugar (deoxyribose) and phosphate groups.