Question

Sugars are technically called carbohydrates, referring to the fact that their formulas are only multiple of $C\left(H_{2}O\right)$. Hexoses therefore have six carbons, twelve hydrogens and six oxygen atoms. Glucose is a hexose. Choose from among the following another hexose.

• A. Fructose
• B. Erythrose
• C. Ribulose
• D. Ribose

Answer 1

The correct option is A Fructose

Classification of monosaccharides

Depending upon the number of carbons in a sugar (monosaccharides), they can be called:

• C3: Triose sugar
• C4: Tetrose sugar
• C5: Pentose sugar
• C6: Hexose sugar

Fructose (C6)

Fructose is a hexose (C6) sugar having a ketone functional group. Its formula is $C_6{H}_{1}2O_6$ .

Erythrose (C4)
Erythrose is a 4-carbon sugar with the chemical formula $C_4{H}_8{O}_4$ .

Ribulose (C5)
Ribulose is a pentose (C5) sugar with the chemical formula $C_5{H}_{1}0O_5$ and has ketone as a functional group.


Ribose (C5)

Ribose is a pentose sugar (C5) with the chemical formula $C_5{H}_{1}0O_5$ and has aldehyde as a functional group.


Final answer: a. Fructose