Chemical Digestion and Absorption

Starch

A carbohydrate that is digested first into oligosaccharides, then into the disaccharide maltose, and finally into glucose, which is absorbed by the small intestine.

Salivary amylase

An enzyme that breaks down starch into oligosaccharides, initiating carbohydrate digestion in the mouth.

Maltase

An enzyme that hydrolyzes maltose into absorbable glucose.

Proteases/Peptidases

Protein-digesting enzymes that are active in the stomach but absent in saliva.

Pepsin

A protease that hydrolyzes peptide bonds, digesting 10%-15% of dietary proteins into smaller polypeptides.

Lipases

Enzymes that digest lipids, including lingual lipase and gastric lipase.

Antral Pumping

A process that breaks up fat into tiny pieces, enhancing the emulsification of lipids in the digestive tract.

Osmosis

The process by which water is absorbed in the digestive tract.

Diarrhea

A condition where too little water is absorbed by the large intestine, leading to rapid movement of feces.

Constipation

A condition characterized by slow movement of feces and excessive water absorption, resulting in hard stool.

Emulsification droplets

Tiny fat droplets formed during the digestion of lipids that are coated in bile acids and lecithin to prevent merging.

Villus core

The central part of a villus in the small intestine where absorbed glucose is transported into the extracellular fluid.

Monosaccharides

Simple sugars absorbed by the enterocyte plasma membranes as soon as they are produced.

Chyme

Partially digested food that mixes with pancreatic amylase in the small intestine.

Brush border enzymes

Enzymes located at the brush border of the small intestine that help hydrolyze oligosaccharides into glucose.