Milk is secreted by

Options

A. Mammary ampullae
B. Mammary bulbs
C. Mammary tubules
D. Mammary alveoli

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the specific structure responsible for the secretion of milk in mammals.

2. **Identifying the Source**: Milk is secreted by mammary glands, which are specialized glands in mammals.

3. **Structure of Mammary Glands**: Mammary glands are modified sweat glands and are classified as endocrine glands due to their function in hormone secretion.

4. **Key Structures in Mammary Glands**: Within the mammary glands, the specific structures responsible for milk secretion are called mammary alveoli.

5. **Function of Mammary Alveoli**: The mammary alveoli are the sites where milk is produced and secreted. They contain lactocytes, which are the cells that synthesize and secrete milk.

6. **Pathway of Milk Secretion**: After being produced in the alveoli, the milk moves through ducts and is eventually excreted from the mammary glands.

7. **Conclusion**: The correct answer to the question is that milk is secreted by mammary alveoli.

**Final Answer**: Milk is secreted by mammary alveoli.

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