Exam 29: A: Physiology of the Digestive System

Intestinal amylase is attached to the brush borders of the villi and function in a process called contact digestion.

All digestive enzymes are classified as extracellular hydrolases.

Enterokinase is converted to trypsinogen by trypsin.

Respiration is inhibited for the 1 to 3 seconds required for food to clear the pharynx during each swallowing.

Enzymes are usually defined as inorganic catalysts.

"Dietary fiber" is a carbohydrate.

Large amounts of cool,dilute,or isotonic fluids are best for replacing fluids quickly during exercise.

Mechanical digestion pushes food against the wall of the small intestine so it can be absorbed.

Micelles contain mostly triglycerides.

Sucrose is an example of a disaccharide.

An enzyme that is a hydrolase breaks water down into hydrogen and oxygen.

The only food that can be digested by gastric juice is protein.

The stimulation of gastric juice secretions occurs in five phases controlled by reflex and chemical mechanisms.

Nucleotidase digests nucleotides.

Because trypsin works in the small intestine,its optimal pH must be less than that of pepsin,which works in the stomach.

The hormone vasoactive intestinal peptide is released when hydrochloric acid and digested food products are in the small intestine.

Paracellular absorption is the absorption of nutrients between cells.

Chief cells and zymogenic cells are the same structures.They function to produce digestive enzymes in the stomach.

Segmentation can be described simply as a mixing movement.

The nutrients absorbed by the lacteals enter the blood by being dumped into the subclavian veins.