Question

Match the sugars in column I with their types given in column II and mark the appropriate choice.

Column I		Column II
$(A)$	Glucose	(i)	Ketohexose
(B)	Fructose	(ii)	Aldohexose
(C)	Ribose	(iii)	Aldotetrose
(D)	Erythrose	(iv)	Aldopentose

• A. $(A)\to (iv),(B)\to (i),(C)\to (iii),(D)\to (ii)$
• B. $(A)\to (iii),(B)\to (iv),(C)\to (i),(D)\to (ii)$
• C. $(A)\to (i),(B)\to (ii),(C)\to (iii),(D)\to (iv)$
• D. $(A)\to (ii),(B)\to (i),(C)\to (iv),(D)\to (iii)$

Answer 1

Answer: (D)

An aldohexose is a hexose with an aldehyde group on one end. The aldohexoses have four chiral centres for a total of $16$ possible aldohexose stereoisomers $(24)$. Of these, only three commonly occur in nature: D-glucose, D-galactose, and D-mannose.
A ketohexose is a ketone-containing hexose (a six-carbon monosaccharide). The most common ketohexoses, each of which represents a pair of enantiomers (D- and L-isomers), include psicose, fructose, sorbose, and tagatose.
Ribose is an aldopentose, which means a pentose sugar with an aldehyde functional group in position one
Erythrose is a tetrose saccharide with the chemical formula $C_4{H}_8{O}_4$. It has one aldehyde group, and so is part of the aldose family.