Chemical digestion in the small intestine involves ________.
A) a significant amount of enzyme secretion by the intestinal mucosa
B) cholecystokinin (CCK), an intestinal hormone responsible for gallbladder contraction
C) secretions from the spleen that contain all enzymes necessary for complete digestion
D) bile salts that help emulsify carbohydrates so that they can be easily digested by enzymatic action
Answer: B