Enterokinase is secreted by

Answer

**Step-by-Step Solution:**

1. **Understanding Enterokinase**: Enterokinase is an enzyme that plays a crucial role in the digestive process. Its primary function is to activate trypsinogen, which is an inactive precursor of the enzyme trypsin.

2. **Function of Trypsin**: Once activated by enterokinase, trypsin becomes functional and is essential for the digestion of proteins. Trypsin helps break down proteins into smaller peptides, which can then be further digested.

3. **Location of Secretion**: Enterokinase is secreted by the mucosa of the small intestine. The mucosal lining of the small intestine is responsible for producing various enzymes and hormones that aid in digestion.

4. **Conclusion**: Therefore, the correct answer to the question "Enterokinase is secreted by" is that it is secreted by the mucosa of the small intestine.

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