A heterocrine gland is one which

Options

A. Has two distinct parts
B. Serves a double function of exocrine and endocrine gland
C. Produces two types of hormones.
D. Occurs in two places.

Answer

### Step-by-Step Solution:

1. **Understanding the Definition of Heterocrine Glands**:
- A heterocrine gland is a type of gland that has both endocrine and exocrine functions. This means it can perform two different roles in the body.

2. **Identifying the Functions of Endocrine and Exocrine Glands**:
- **Endocrine Glands**: These glands are ductless and secrete hormones directly into the bloodstream. They regulate various bodily functions by releasing hormones that travel through the blood to target organs.
- **Exocrine Glands**: These glands have ducts and secrete their products (like enzymes or other substances) directly to the site of action (such as the digestive tract) through these ducts.

3. **Example of a Heterocrine Gland**:
- The pancreas is a classic example of a heterocrine gland. It serves both functions:
- As an **endocrine gland**, it secretes insulin directly into the blood to regulate blood sugar levels.
- As an **exocrine gland**, it produces digestive enzymes and juices that are secreted through the pancreatic duct into the small intestine.

4. **Conclusion**:
- Therefore, a heterocrine gland is defined as one that serves the double function of exocrine and endocrine glands.

### Final Answer:
A heterocrine gland is one which serves the double function of exocrine and endocrine glands.

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