Question

Glucose and fructose are examples of
A. Monosaccharide
B. Disaccharide
C. Polysaccharide
D. None of these

Answer 1

Hint: Carbohydrates are polyhydroxy aldehydes or ketones or such compounds that give polyhydroxy aldehydes or ketones on hydrolysis. Carbohydrates are made up of carbon, hydrogen, and oxygen in ratio \(1:2:1\).

Complete answer: Carbohydrates have the general formula \({C_n}{H_{2n}}{O_n}\). Carbohydrates reduce cupric ions, which is the concept behind the chemical detection of carbohydrates using Fehling's solution test.
a) Glucose: Glucose is a four chiral carbon compound. It has two forms, the L-form, and the D-form. The L form is known as Laevo and the D form is known as Dextrose. The glucose is also known as blood sugar or grape sugar. It is a monosaccharide as it has six carbons. The human blood has eighty to one hundred twenty milligrams of glucose per one hundred milliliters. Glucose shows optical activity.
b) Fructose: Fructose is also known as levulose. It is the sweetest sugar found that has a furanose ring structure. It also reduces copper. It is a monosaccharide as it has six carbons.
Thus, based on the above information we can conclude that glucose and fructose are examples of monosaccharides.
Hence, the correct answer is option A.

Note: Monosaccharides are the three to seven carbon compounds. The carbon atoms are linked together in a chain. Monosaccharides have at least one chiral carbon atom. They are all very sweet in nature. All monosaccharides tend to reduce the copper from cupric to cuprous ion form. Also, all monosaccharides show optical activity, which means that they rotate the polarized light either clockwise or anticlockwise.