Schleiden and Schwann proposed

Options

A. Brownian movment
B. Cell theory
C. Protoplasm as physical basis of life
D. None of the above

Answer

**Step-by-Step Solution:**

1. **Identify the Scientists**: The question mentions two scientists, Schleiden and Schwann. It is important to know who they are and their contributions to biology.

2. **Understand Their Contributions**:
- **Schleiden**: In 1838, Matthias Schleiden proposed that all plant tissues are composed of cells.
- **Schwann**: In 1839, Theodor Schwann extended this idea to animals, stating that all animal tissues are also made up of cells.

3. **Combine Their Findings**: Schleiden and Schwann’s findings together laid the foundation for a significant biological concept.

4. **Formulate the Cell Theory**: The combination of their ideas led to the formulation of the Cell Theory, which states:
- All living organisms are composed of one or more cells.
- The cell is the basic unit of life.
- All cells arise from pre-existing cells.

5. **Evaluate the Options**: The question provides four options:
- a. Brownian movement
- b. Cell theory
- c. Protoplasma as physical basis of life
- d. None of the above
- Based on the contributions of Schleiden and Schwann, the correct answer is **b. Cell theory**.

6. **Conclude the Answer**: Therefore, the answer to the question is **option B: Cell theory**.

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