Trypsinogen is an inactive enzyme of pancreatic juice. An enzyme, enterokinase, activates it. Which tissue/cells secrete this enzyme?/How is it activated?

Explanation

**Step-by-Step Solution:**

1. **Understanding Trypsinogen**:
- Trypsinogen is an inactive precursor (zymogen) of the enzyme trypsin, which is produced in the pancreas and is part of pancreatic juice.

2. **Role of Enterokinase**:
- Enterokinase is an enzyme that plays a crucial role in the activation of trypsinogen. It converts trypsinogen into its active form, trypsin.

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