Question

Intestinal secretions contain 

A. Potassium in a concentration similar to that in extracellular fluid.

B. Enzymes that are released when the vagus nerve is stimulated. 

C. Enzymes that hydrolyze disaccharides. 

D. Enzymes that hydrolyze mono saccharides. 

E. Enzymes that activate pancreatic proteolyic enzymes. 

Answer 1

A. False The concentration is higher, due partly to potassium released from cast off cells. 

B. False Intestinal secretion is not under vagal control; its enzymes are thought to be constituents of the mucosal cells and released when these are cast off into the lumen. 

C. True The mucosal cell brush border contains these enzymes, e.g. maltase and lactase. 

D. False Monosaccharides are end-products of digestion and absorbed as such. 

E. True For example, enterokinase which converts trypsinogen to trypsin.