Deoxyribose sugar:
1. Deoxyribose is the pentose sugar of DNA with five carbon atoms.
2. Four out of the five carbon atoms plus a single atom of oxygen form a five-membered ring.
3. The fifth carbon is outside the ring and forms a part of the –CH2 group.
4. Deoxyribose has only two hydroxyl (-OH) groups (on carbons 3’ and 5’) and thus can form only two deoxyribonucleotides, the 3’ and 5’ phosphate derivatives.
Ribose sugar:
1. Ribose is the pentose sugar of RNA with five carbons
2. It has an identical structure to DNA except that there is an hydroxyl (-OH) group instead of hydrogen on carbon atom 2’.
3. Ribose has free –OH groups on carbons 2’, 3’ and 5’.
4. The phosphate can attach at any of these three positions.
