In animals, chalones are substance resposible for

Options

A. Regeneration
B. Ageing
C. Development
D. Parthenogenesis

Answer

**Step-by-Step Solution:**

1. **Understanding Chalones**: Chalones are small, water-soluble polypeptides that are proteinaceous in nature. They are released by specific tissues in the body.

2. **Function of Chalones**: The primary role of chalones is to act as potent mitotic inhibitors. This means they inhibit or prevent the proliferation (division) of mature cells.

3. **Chalones and Aging**: Recent studies have indicated a connection between chalones and aging. As mitotic inhibitors, chalones may contribute to cellular senescence, which is the process where cells lose their ability to proliferate. This loss of proliferative capacity is associated with aging.

4. **Evaluating Options**:
- **Regeneration**: Chalones are not responsible for regeneration, which is the restoration of damaged parts.
- **Aging**: Chalones are indeed involved in aging, as they may influence cellular senescence.
- **Development**: Chalones do not play a role in development, which refers to growth processes.
- **Parthenogenesis**: This is a form of asexual reproduction and is unrelated to the function of chalones.

5. **Conclusion**: Based on the analysis, the correct answer is that chalones are substances responsible for **aging**.

**Final Answer**: Chalones are substances responsible for aging.

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