Secretion of milk is stimulated by ________

Answer

**Step-by-Step Solution:**

1. **Identify the Context**: The question asks about the stimulation of milk secretion, which is a physiological process related to lactation.

2. **Understand the Role of Hormones**: Hormones are chemical messengers in the body that regulate various functions, including growth, metabolism, and reproduction.

3. **Locate the Relevant Hormone**: The hormone responsible for stimulating milk secretion is known as prolactin.

4. **Source of Prolactin**: Prolactin is secreted by the anterior lobe of the pituitary gland, which is located at the base of the brain.

5. **Function of Prolactin**: The primary function of prolactin is to promote the growth and development of mammary glands and stimulate milk production during and after pregnancy.

6. **Conclusion**: Therefore, the secretion of milk is stimulated by the prolactin hormone.

**Final Answer**: The secretion of milk is stimulated by **prolactin**.

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