Who formulated the cell theory?

Answer

**Step-by-Step Solution:**

1. **Identify the Scientists**: The cell theory was formulated by two primary scientists, Matthias Schleiden and Theodor Schwann.

2. **Understanding Their Contribution**: Schleiden and Schwann proposed that all living organisms are composed of cells, which is a fundamental concept of the cell theory.

3. **Expansion of the Theory**: Later, another scientist, Rudolf Virchow, contributed to the cell theory by stating that all cells arise from pre-existing cells. This addition is crucial as it emphasizes the continuity of life through cellular division.

4. **Conclusion**: Therefore, the cell theory is attributed to the contributions of Schleiden, Schwann, and Virchow, with the first two formulating the original theory and Virchow expanding upon it.

**Final Answer**: The cell theory was formulated by Matthias Schleiden and Theodor Schwann, with Rudolf Virchow later expanding it.

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