During the digestion of proteins, the final products absorbed by the intestinal epithelial cells are primarily in which form?

Solution

1. Protein digestion results in the formation of $\text{amino acids}$, $\text{dipeptides}$, and $\text{tripeptides}$.
2. These products are transported across the apical membrane of enterocytes via specific transporters.
3. Intracellular peptidases further hydrolyze dipeptides and tripeptides into free amino acids before they enter the blood.
4. Hence the answer is (B).