Which of the following transport steps in an intestinal epit

Which of the following transport steps in an intestinal epithelial cell can, under certain conditions, occur against a concentration gradient? (uptake refers to \"into the cell\", export: \"out of the cell\")

a. uptake of glucose

b. export of glucose

c. uptake of Na+ at the basolateral plasma membrane

d. uptake of Na+ at the apical plasma membrane

e. export of K+

Solution

a. uptake of glucose

Glucose will be seen getting imported against its concentration gradient from the intestinal lumen across the apical surface of the epithelial cells with the help of a two-Na+/one-glucose symporter which is found to be located in the microvillar membranes.