Dissaccharides

Ans. is ‘c’ i.e., Small intestine

• Digestion of disaccharides (maltose, sucrose and lactose) occurs by the enzymes present in brush border os small intestinal epithelial cells.
• Maltase (a-glucosidase) breaks 1: 4 linkages in maltose and maltotriose and releases glucose (two molecules of glucose from maltose and three molecules of glucose from maltotriose). Isomaltase (a-limit dextrinase) breaks 1 : 6 a linkages of alpha-limit dextrin and releases glucose. Isomaltase dextrinase) is the only enzyme that attacks 1 : 6a linkage.
• Sucrose is hydrolysed into fructose and glucose by sucrase (an enzyme present in brush border of intestinal epithelium). Lactose is hydrolysed into galactose and glucose by lactase ((3-glucosidase). Trehalase hydrolyzes trehelose (a 1:1 a – linked dimer of glucose) into two glucose molecules. Trehalose is found in mushrooms.

Ans. A. Sucrose

Sucrose contains glucose and fructose. Sucrose is not a reducing sugar; and it will not form osazone. This is because the linkage involves first carbon of glucose and second carbon of fructose, and free reducing groups are not available.