Solution:

• An aldose is a monosaccharide (a simple sugar) with a carbon backbone chain with a carbonyl group on the endmost carbon atom, making it an aldehyde, and hydroxyl groups connected to all the other carbon atoms.
• Aldoses can be distinguished from ketoses, which have the carbonyl group away from the end of the molecule, and are therefore ketones.
• Aldehydes and Ketones are often called as methanoyl or formyl group.
• The carbon atom of this group has 2 remaining bonds that might be occupied by aryl or alkyl or substituents.
• If neither of these substituents is hydrogen, the compound is a Ketone.
• If at least one is hydrogen, the compound is an Aldehyde.