In males , the essential hormone for secondary sexual characteristics is
Or
The hormone which brings about characteristics changes in the male at puberty is called

Options

A. Testosterone
B. Androgen
C. Follicle stimulating hormone
D. None of these.

Answer

**Step-by-Step Solution:**

1. **Understanding Puberty in Males:**
- Puberty is a developmental stage where males undergo various physical and hormonal changes. This stage is marked by the development of secondary sexual characteristics.

2. **Role of Gonadotropin-Releasing Hormone (GnRH):**
- At the onset of puberty, the hypothalamus increases the secretion of Gonadotropin-Releasing Hormone (GnRH). This hormone is crucial as it stimulates the pituitary gland.

3. **Pituitary Gland Activation:**
- The increase in GnRH from the hypothalamus prompts the pituitary gland to release two important hormones: Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH).

4. **Action of Luteinizing Hormone (LH):**
- LH specifically targets the Leydig cells (interstitial cells) located in the testes. These cells are responsible for producing testosterone, the primary male sex hormone.

5. **Testosterone and Secondary Sexual Characteristics:**
- Testosterone is essential for the development of secondary sexual characteristics in males, such as increased muscle mass, deepening of the voice, and growth of body hair. It also plays a critical role in spermatogenesis, the process of sperm formation.

6. **Conclusion:**
- Therefore, the essential hormone for secondary sexual characteristics in males, particularly during puberty, is testosterone.

**Final Answer:**
The essential hormone for secondary sexual characteristics in males is **testosterone**.

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