State true (T) or false (F).
Mammary glands develop in females during puberty.

Answer

**Step-by-Step Solution:**

1. **Understanding Mammary Glands**: Mammary glands are specialized organs in mammals that are responsible for producing milk. They are present in both males and females, but they develop fully only in females.

2. **Development During Puberty**: During puberty, females undergo various physical changes due to hormonal changes in their bodies. One of these changes includes the development of mammary glands.

3. **Role of Hormones**: The hormone responsible for the development of mammary glands in females is called estrogen. Estrogen levels rise during puberty, leading to the development of these glands.

4. **Conclusion**: Since mammary glands develop in females during puberty due to the influence of estrogen, the statement "Mammary glands develop in females during puberty" is true.

**Final Answer**: True (T)

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