Ribose is a
pentose (5-carbon) sugar - formula C
5H
10O
5.
It forms part of
RNA, also
ATP (and
ADP and
AMP) and
NAD (and
NADP).
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.