Topic: Biology - Digestion and Absorption Step 1: Understanding the Question:
The question relates to the activation of pancreatic enzymes in the small intestine. Trypsinogen is a proenzyme (inactive) that needs to be triggered to function. Step 2: Detailed Explanation:
1. The pancreas secretes inactive enzymes into the duodenum to prevent self-digestion of the pancreatic tissue.
2. Trypsinogen is one such zymogen.
3. The intestinal mucosa secretes an enzyme called enterokinase (also known as enteropeptidase).
4. Enterokinase specifically cleaves a peptide from trypsinogen to convert it into the active protease, trypsin.
5. Once trypsin is formed, it acts autocatalytically to activate more trypsinogen and other enzymes like chymotrypsinogen and procarboxypeptidase. Step 3: Final Answer:
The correct enzyme is Enterokinase.