ANATOMY

Detailed explanation-1: -The final step in digestion of dietary carbohydrates and proteins occurs on the face of small intestinal enterocytes, in the immediate vicinity of the transporters which will ferry the resulting sugars and amino acids into the epithelial cells.

Detailed explanation-2: -Disaccharidases are located in the brush-border membrane of mature enterocytes of the small intestine. The major disaccharidases found in humans are ß-galactosidase (lactase) and -glucosidases (sucrase, isomaltase, and glucoamylase). Lactase hydrolyzes lactose to glucose and galactose.

Detailed explanation-3: -The microvilli that constitute the brush border have enzymes for this final part of digestion anchored into their apical plasma membrane as integral membrane proteins. These enzymes are found near to the transporters that will then allow absorption of the digested nutrients.

Detailed explanation-4: -Also, improper digestion of other nutrients (fats, carbohydrates, or proteins) may cause bloating. Brush border hydrolases – Enzymes present in the brush border or microvilli of the small intestine, which break down disaccharides and starches; examples are sucrase, isomaltase, and lactase.

Detailed explanation-5: -The most important brush border enzymes are dextrinase and glucoamylase, which further break down oligosaccharides. Other brush border enzymes are maltase, sucrase, and lactase. Lactase is absent in most adult humans and for them lactose, like most poly-saccharides, is not digested in the small intestine.