Answer: see below
Explanation: aldoses and ketoses differ in that aldoses have a terminal aldhyde group and ketoses have the -C-CO-C- ketone structure. Aldehydes are more reactive and can be oxidised directly to carboxylic acids. Ketones require the carbon chain to break at the carbonyl group. In cyclic form aldohexoses form a six member ring, ketohexoses a five member ring.
examples of aldoses
Threose CH2OH-CHOH-CHOH-CHO
glyceraldehyde CH2OH-CHOH-CHO
mannose, glucose, altrose, allose etc CH2OH(CHOH)4-CHO
deoxyribose H-(CHOH)3-CH2-CH2OH
ketoses
dihydroxyacetone CHOH-CO-CHOH
ribulose, xylulose CH2OH-(CHOH)2-CO-CH2OH
sedoheptulose CH2OH-(CHOH)-CO-CH2OH
erythrulose CH2OH-CHOH-CO-CHOH
