JEE Main 20268 AprilEvening Shift
- Exam
- JEE Main
- Year
- 2026
- Date
- 8 April
- Shift
- Evening Shift
- Subject
- Chemistry
- Chapter
- Biomolecules
JEE Main 2026 · 8 April · Evening Shift · Chemistry · Biomolecules
The incorrect statement from the following with respect to...
The incorrect statement from the following with respect to carbohydrates is:
Options
- AAll monosaccharides are reducing sugars.
- BThe monosaccharide units obtained from hydrolysis of oligosaccharides are always the same.
- CStarch and cellulose are typical examples of polysaccharides, which are very high molecular weight compounds of more than ten monosaccharide units.
- DOpen chain and cyclic structures co-exist at equilibrium that are responsible for certain properties as in the case of -glucose.
Correct answer
B. The monosaccharide units obtained from hydrolysis of oligosaccharides are always the same.
Step-by-step solution
Statement (A) is correct because all monosaccharides contain a free aldehyde or ketonic group (or exist in equilibrium with it) and act as reducing sugars.
Statement (B) is incorrect because the hydrolysis of oligosaccharides can yield either the same or different monosaccharide units. For example, sucrose is an oligosaccharide (disaccharide) that yields one molecule of glucose and one molecule of fructose upon hydrolysis, whereas maltose yields two molecules of glucose.
Statement (C) is correct as polysaccharides like starch and cellulose are high molecular weight polymers containing more than ten monosaccharide units.
Statement (D) is correct because in an aqueous solution, -glucose exists in an equilibrium between its open-chain form and its cyclic hemiacetal forms ( and anomers), which explains its mutarotation and other properties.
Answer: The monosaccharide units obtained from hydrolysis of oligosaccharides are always the same.
Statement (B) is incorrect because the hydrolysis of oligosaccharides can yield either the same or different monosaccharide units. For example, sucrose is an oligosaccharide (disaccharide) that yields one molecule of glucose and one molecule of fructose upon hydrolysis, whereas maltose yields two molecules of glucose.
Statement (C) is correct as polysaccharides like starch and cellulose are high molecular weight polymers containing more than ten monosaccharide units.
Statement (D) is correct because in an aqueous solution, -glucose exists in an equilibrium between its open-chain form and its cyclic hemiacetal forms ( and anomers), which explains its mutarotation and other properties.
Answer: The monosaccharide units obtained from hydrolysis of oligosaccharides are always the same.