Target Exam

CUET

Subject

Chemistry

Chapter

Organic: Biomolecules

Question:

Read the passage carefully and answer the questions.

Carbohydrates such as cane sugar, glucose, starch etc. belong to a class of naturally occurring organic compounds. Structurally these are polyhydroxy aldehydes or ketones or the compounds which produce such units on hydrolysis. Carbohydrates which are sweet in taste are called sugars. Theses sugars can be reducing or non-reducing. Monosaccharides cannot be hydrolyzed to simpler units whereas Oligosaccharides yield two to ten monosaccharide units on hydrolysis. Polysaccharides yield large number of monosaccharide units on hydrolysis. This class of biomolecules is essential for living systems as they serve as storage molecules in plants and animals. In addition, they provide raw materials for important industries like furniture, textiles, paper, lacquers and breweries. Two aldopentose form important constituents of nucleic acids. Carbohydrates are also called saccharides (Greek: sakcharon which means sugar). Sugar which is used in household and in milk also comes under this class of biomolecules.

Sucrose on hydrolysis yields

Options:

Glucose and fructose

Two molecules of glucose

Glucose and galactose

Galactose and Fructose

Correct Answer:

Glucose and fructose

Explanation:

The correct answer is Option (1) → Glucose and fructose

  • Sucrose is a disaccharide composed of one molecule of glucose and one molecule of fructose joined by a glycosidic bond.

  • When hydrolysis occurs (using acid or the enzyme sucrase), this bond breaks and releases glucose + fructose.

Why Other Options Are Incorrect

  • Two molecules of glucose – This is maltose, not sucrose.

  • Glucose and galactose – This combination forms lactose, not sucrose.

  • Galactose and fructose – Not a standard natural disaccharide related to sucrose.