JEE Main · 2021 · 17 Mar 2021 · Shift 2 · Biomolecules

Fructose is an example of:

(A)Heptose
(B)Aldohexose
(C)Ketohexose✓ Correct
(D)Pyranose

Answer: (C)

Solution

Fructose is a monosaccharide with the molecular formula

C_{6} H_{12} O_{6}

. It contains six carbon atoms (hexose) and has a ketone functional group at the C-2 position, making it a ketohexose. In contrast, glucose is an aldohexose (aldehyde group at C-1). Heptose refers to seven-carbon sugars, and pyranose refers to the six-membered ring form of sugars. Therefore, fructose is classified as a ketohexose.

JEE Main · 2021 · 17 Mar 2021 · Shift 2 · Single correct option

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