BIOMOLECULES AND ENZYMES

Detailed explanation-1: -Cyclic hemiacetal formation. In a monosaccharide, the carbonyl (C=O) and alcohol group (OH) exist within the same molecule, so they can react forming a cyclic hemiacetal (or hemiketal, in the case of ketoses). The resulting structure will be an intramolecular cyclic hemiacetal.

Detailed explanation-2: -Monosaccharides exist predominantly as cyclic hemiacetals, referred to as pyranose (6-membered ring) and furanose (5-membered ring) forms.

Detailed explanation-3: -Yes, glucose can form an intramolecular cyclic hemiacetal. Let’s now show the formation of hemiacetal of glucose starting from its open structure (Fischer projection).

Detailed explanation-4: -In monosaccharides the joining of one hydroxyl group (–C–OH) to the carbonyl carbon (–C O) produces a cyclic structure.

Detailed explanation-5: -The cyclic form of glucose is a six-membered ring, with an intramolecular hemiacetal formed by attack of the hydroxl on carbon #5 to the aldehyde carbon (carbon #1, also called the anomeric carbon in carbohydrate terminology).