Ribose is a pentose
(5-carbon) sugar - formula C5
It forms part of RNA
, also ATP
) and NAD
Notice the 5 carbon atoms (grey)
forming the backbone of the molecule, and the oxygen atom (red)
in the ring - which is a 5 sided ring, unlike glucose.
The hydrogen atoms (white) are either attached directly to the carbons, or via oxygen as -OH groups - at an angle.
Only the carbon outside the ring has 2 single hydrogens and an OH group. Carbon 2 (labelled as C2) has a single hydrogen and an -OH group, whereas deoxyribose has only 2 hydrogen atoms in this position.