Exam 29: A: Physiology of the Digestive System

Retropulsion forces the chime in the stomach to move backwards.

The process of elimination is simply the expulsion of the residues of digestion from the digestive tract.

To propel food from the pharynx into the esophagus,three openings must be blocked.

Most digestive enzymes are synthesized and secreted as inactive proenzymes.

Secretin causes the production of pancreatic fluid high in enzyme content but low in bicarbonate.

Chylomicrons are formed in the epithelial cells lining the small intestine.

Because enzymes are not changed by the chemical reactions they catalyze,digestive enzymes rarely need to be made.

Enzymes are pH sensitive because differences in the hydrogen ion concentration can affect the shape of the protein molecule.