Question

The glucose concentration is higher in the cytosol of an intestinal epithelial cell (IEC) than it is in the intestinal lumen and in the basal extracellular fluid. Thus, to prevent glucose from leaving the IEC and going into the intestine lumen and to allow glucose to enter into the blood:______ a. IEC symporters are found only in the plasma membrane (PM) facing the intestine lumen. b. IEC Na+/glucose symporters are found only in the plasma membrane (PM) facing the basal extracellular fluid c. IEC glucose uniporters are found only in the PM facing the basal extracellular fluid. d. IEC glucose uniporters are found only in the PM facing the intestine lumen. e. Both a and c are correct answers.

Answer 1

Answer:

The correct option is b. "IEC Na+/glucose symporters are found only in the plasma membrane (PM) facing the basal extracellular fluid"

Explanation:

The glucose in the intestine is a product of digestion and needs to be absorbed into the blood so it can be transported to where needed. Glucose moves out of the IEC with the combined action of sodium ions. The sodium-glucose symporter opens and allows for this pair to move out only when one of each is attached to the symporter. The movement of glucose is regulated in this way.