Question

Intestinal epithelial cells are used as an example of a cell with distinctly localized transmembrane proteins. What strategy/structure prevents Na /Glucose symporters from laterally diffusing from the apical side to the lateral or basal sides of the cell

Answer 1

Step-by-step explanation:

Glucose/Na symporters cannot diffuse across from the apical side to the lateral or basal sides because of the lipid bilayer (the hydrophobic tail/part will prevent it from crossing). However, a facilitated diffusion approach is "endorsed" here, a specialized carrier protein called glucose or sodium transporter is used to transfer/diffuse the glucose or sodium to the basal side of the cell.

NOTE: These lipid bilayers are present in the cell membrane and are actually responsible for the selective nature of what goes in or out of the cell. The bilayer consists of the hydrophilic head and the hydrophobic tail.