Final answer:
In RNA, the pentose sugar component of nucleotides is called ribose, which has a hydroxyl group at the 2' carbon. This sugar is key to distinguishing RNA from DNA, whose sugar is deoxyribose.
Step-by-step explanation:
The nucleotides used to make RNA and DNA are comprised of three main parts: a nitrogenous base, a phosphate group, and a pentose sugar. In RNA, the sugar molecule is called ribose, which differentiates it from the sugar found in DNA, known as deoxyribose. Ribose has a hydroxyl group at the 2' carbon, making it distinct from deoxyribose, which instead has just a hydrogen atom at the same position. This difference is crucial as it contributes to the structural and functional distinctions between DNA and RNA.