What is one of the main postulates of the cell theory ?

Options

A. New cells arise from the old cells.
B. Old cells can convert into new cells.
C. All living things are composed of one cell.
D. Only one cell functions at a time.

Answer

**Step-by-Step Solution:**

1. **Understanding Cell Theory**: The cell theory is a fundamental concept in biology that explains the properties and functions of cells. It was proposed in the years 1838-1839 by scientists Schleiden and Schwann.

2. **Identifying the Postulates**: The cell theory consists of three main postulates:
- All living organisms are composed of one or more cells.
- The cell is the basic unit of life.
- New cells arise from existing cells through the process of cell division.

3. **Evaluating the Options**: The question presents four options, and we need to determine which one aligns with the main postulates of cell theory:
- Option A: New cells arise from old cells. (This aligns with the postulate that new cells are formed through cell division.)
- Option B: Old cells can convert into new cells. (This is misleading; cells divide rather than convert.)
- Option C: All living things are composed of one cell. (This is incorrect as many organisms are multicellular.)
- Option D: Only one cell functions at a time. (This is incorrect; multiple cells can function simultaneously.)

4. **Selecting the Correct Answer**: Based on the evaluation, the correct answer is Option A: "New cells arise from old cells," which is one of the main postulates of the cell theory.

**Final Answer**: One of the main postulates of the cell theory is that new cells arise from old cells.

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