Cell is the fundarmental structural and functional unit of all living organisms because

Options

A. Unicellular organisms are incapable of independent existance
B. The cell is the basic unit of life
C. Anything less than a complete structure of a cell does ensure independent living
D. Essential life function can be performed in only multicellular organisms

Answer

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

1. **Understanding the Question**: The question states that the cell is the fundamental structural and functional unit of all living organisms. We need to explore the reasons behind this assertion.

2. **Evaluating the Options**:
- **Option 1**: "Unicellular organisms are incapable of independent existence."
- This statement is incorrect because unicellular organisms, such as bacteria and amoebas, can live independently and perform all necessary life functions.

- **Option 2**: "The cell is the basic unit of life."
- This statement is correct. Cells are indeed the smallest units that can carry out all life processes. They can organize into tissues, organs, and systems, which ultimately form an organism.

- **Option 3**: "Anything less than a complete structure of a cell does ensure independent living."
- This statement is incorrect. Structures smaller than a cell (like organelles) cannot survive independently; they rely on the cell to function.

- **Option 4**: "Essential life functions can be performed in only multicellular organisms."
- This statement is also incorrect. Many unicellular organisms can perform essential life functions independently, demonstrating that single cells can sustain life.

3. **Conclusion**: After evaluating all options, the correct reason for why the cell is considered the fundamental structural and functional unit of all living organisms is that "the cell is the basic unit of life."

**Final Answer**: The cell is the basic unit of life, which is why it is the fundamental structural and functional unit of all living organisms.

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