The absorptive epithelia in the gut are considered "polarized" because
A)thick and thin filaments are present.
B)they pump wastes into the lumen while pumping nutrients toward the blood.
C)the colours seen on the top and bottom of the cells are different.
D)they must fire action potentials to absorb most nutrients.
E)the structures on the apical surface are different than those on the basal surface.

Question

Quizplus · Accepted Answer

The statement "the structures on the apical surface are different than those on the basal surface" is the correct explanation for why the absorptive epithelia in the gut are considered polarized. In polarized epithelial cells, the apical surface (facing the lumen) has microvilli and specific transporters for nutrient uptake, while the basal surface (facing the blood) has different types of transporters for nutrient release into the bloodstream. This differentiation of structures allows for efficient absorption and transport of nutrients in one direction.

The Absorptive Epithelia in the Gut Are Considered "Polarized" Because