Small cells are metabolically active as they have

Options

A. higher nucleocytoplasmic ratio
B. higher surface area per unit volume
C. more cytoplasm
D. both (1) & (2) are correct.

Answer

**Step-by-Step Solution:**

1. **Understanding Cell Size and Metabolism:**
- Small cells are known to be metabolically active. This is primarily due to their size, which allows for more efficient cellular processes.

2. **Nuclear-Cytoplasmic Ratio:**
- The nuclear-cytoplasmic ratio is a key factor in determining a cell's metabolic activity. It refers to the volume of the nucleus compared to the volume of the cytoplasm.
- In smaller cells, the nucleus is relatively small compared to the cytoplasm, resulting in a higher nuclear-cytoplasmic ratio.

3. **Surface Area to Volume Ratio:**
- Smaller cells have a higher surface area to volume ratio. This means that there is more surface area available for the exchange of materials (nutrients and waste) relative to the volume of the cell.
- A higher surface area allows for more efficient absorption of nutrients and expulsion of waste products.

4. **Cytoplasm's Role in Metabolism:**
- The cytoplasm contains organelles that are essential for metabolic processes, such as energy production and synthesis of biomolecules.
- If the cytoplasm is larger (as in smaller cells), it can accommodate more organelles, leading to higher metabolic activity.

5. **Conclusion:**
- Therefore, small cells are metabolically active because they have a higher nuclear-cytoplasmic ratio and a greater surface area per unit volume, which facilitates efficient metabolic processes.

**Final Answer:**
Small cells are metabolically active because they have a higher nuclear-cytoplasmic ratio and a higher surface area per unit volume.

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