The ________is the fundamental structural and functional unit of all living beings

Options

A. cell
B. centrome
C. nucleus
D. nucleolus

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term that describes the fundamental structural and functional unit of all living beings.

2. **Identifying Key Terms**: The key terms here are "fundamental," "structural," "functional," and "unit of all living beings."

3. **Reviewing Options**: The options provided are:
- Cell
- Centrosome
- Nucleus
- Nucleolus

4. **Analyzing Each Option**:
- **Centrosome**: This is an organelle involved in cell division but is not the basic unit of life.
- **Nucleus**: This is the organelle that contains genetic material but does not represent the entire unit of life.
- **Nucleolus**: This is a structure within the nucleus that helps in ribosome production but is not a standalone unit of life.
- **Cell**: This is the basic unit of life. All living organisms are made up of cells, whether they are unicellular (single-celled) or multicellular (many-celled).

5. **Conclusion**: Since the cell is the basic unit of life and is responsible for all essential functions, the correct answer to fill in the blank is "Cell."

**Final Answer**: The **cell** is the fundamental structural and functional unit of all living beings.

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