Enterokinase is

Options

A. Pancreatic hormone
B. Intestinal hormone
C. Pancreatic enzyme
D. Component of intestinal juice

Answer

**Step-by-Step Solution:**

1. **Understanding Enterokinase**: Enterokinase is an enzyme that plays a crucial role in the digestive process. It is primarily involved in the activation of trypsinogen, which is an inactive precursor of the enzyme trypsin.

2. **Source of Enterokinase**: Enterokinase is secreted by the mucosal cells of the duodenum, which is the first part of the small intestine. Specifically, it is produced by the Brunner's glands located in the duodenal lining.

3. **Function of Enterokinase**: The main function of enterokinase is to convert trypsinogen into trypsin. Trypsin is an active enzyme that further aids in the digestion of proteins in the small intestine.

4. **Classification of Enterokinase**: Given the options provided (pancreatic hormone, intestinal hormone, pancreatic enzyme, component of intestinal juice), enterokinase is best classified as a component of intestinal juice. It is not a hormone and does not originate from the pancreas, which rules out the other options.

5. **Conclusion**: Therefore, the correct answer to the question "Enterokinase is" is that it is a component of intestinal juice.

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