Over secretion and low secretion of HG at childhood leads to respectively.

Answer

**Step-by-Step Text Solution:**

1. **Identify the Hormone**: The hormone referred to as "Hg" in the question is the Growth Hormone (GH), which is secreted by the pituitary gland.

2. **Understand the Role of Growth Hormone**: Growth hormone is crucial for growth and development during childhood. It stimulates growth in tissues and bones.

3. **Effects of Over Secretion**:
- When there is an over secretion of growth hormone during childhood, it leads to a condition known as gigantism.
- Gigantism is characterized by excessive growth, resulting in an abnormally tall stature and increased body girth.

4. **Effects of Low Secretion**:
- Conversely, if there is a low secretion of growth hormone during childhood, it leads to a condition known as dwarfism.
- Dwarfism is characterized by short stature and underdevelopment of the body.

5. **Conclusion**: Therefore, the effects of growth hormone secretion during childhood can be summarized as follows:
- Over secretion leads to gigantism.
- Low secretion leads to dwarfism.

**Final Answer**: Over secretion of Growth Hormone (GH) during childhood leads to gigantism, while low secretion leads to dwarfism.

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