The main arena of various types of activities of a cell is

Options

A. nucleus
B. plasma membrane
C. mitochondrian
D. cytoplasm

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the main area where various types of activities of a cell occur. This means we need to identify the part of the cell that is primarily responsible for carrying out cellular functions.

2. **Analyzing the Options**:
- **Nucleus**: This is the part of the cell that contains genetic material (DNA) and is responsible for cell division and the regulation of gene expression. While it plays a crucial role, it is not the main site for all cellular activities.
- **Plasma Membrane**: This is the outer boundary of the cell that protects the cell and regulates what enters and exits. It is important for communication and transport but does not carry out the majority of cellular activities.
- **Mitochondria**: Known as the powerhouse of the cell, mitochondria are responsible for producing ATP (energy) through cellular respiration. However, they are just one of the many organelles in the cell.
- **Cytoplasm**: This is the jelly-like fluid that fills the cell and contains all the organelles. It is where most of the cellular activities take place, including metabolic processes, synthesis of proteins, and storage of molecules.

3. **Conclusion**: After analyzing all the options, it is clear that the cytoplasm is the main arena for various types of activities of a cell. It houses the organelles and is the site for metabolic reactions.

4. **Final Answer**: The main arena of various types of activities of a cell is the **cytoplasm**.

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