This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gastrointestinal System, Subject name: Physiology
[{'content': 'Which of the following is not a constituent of the succus entericus ? \nSelect and explain. \nA. Erepsin, B. Enterokinase, C. Invease, D. Trypsin', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Trypsin is formed from trypsinogen in the small intestine. It is not a constituent of the intestinal juice Intestinal juice or succus entericus- Small intestine-crypts of Lieberkuhn Enzymes present in the succus entericus are: Protein digestion: aminopeptidases ,carboxypeptidases. Erepsin: conves proteoses & peptones into amino acids Enterokinase: it conves trypsinogen (secreted by pancreas) into trypsin. Carbohydrate Digestion: Invease (sucrose conveed to glucose and fructose) Maltase, glucoamylase, and lactase', 'role': 'assistant'}]