12. Cows digest proteins into smaller molecules called peptides through the use of an enzyme called pepsin. Aqueous solutions taken from the contents of a cow's stomach are found to have many more hydrogen ions
(H+) than hydroxide ions (OH-). A veterinarian is attempting to conduct an experiment that mimics protein
digestion and has the following four test tubes set up. Which would you expect to have the greatest
concentration of peptides?
(A) Test tube 1: protein and pepsin in water at pH 1.4
(B) Test tube 2: protein and pepsin in water at pH 8.2
(C) Test tube 3: protein in water at pH 7.6
(D) Test tube 4: pepsin in water at pH 1.7