Chemistry - Biomolecules Question with Solution | TestHub

Question Explanation:

The question asks which statements about monosaccharides and their cyclic forms are incorrect.

Concept:

This question is based on Monosaccharide solubility, Anomers, Furanose/Pyranose ring formation, Sugar structure.

Solution:

1. Monosaccharides are insoluble in water → Incorrect . Monosaccharides are highly soluble in water because they are polar and can form hydrogen bonds.

2. “Anomers of a cyclic monosaccharide differ in the position of the OH group at any carbon.” → Incorrect.

Anomers differ only in the configuration of the OH group at the hemiacetal (anomeric) carbon , not at any other carbon.

3. In D-ribose, the OH used to form the furanose ring is on C4 → Correct .

The five-membered ring forms via the C1 aldehyde and C4 OH.

4. Aldopentoses and ketohexoses form pyranose rings in solution → Incorrect . Aldopentoses and ketohexoses form furanose rings in solution.