The plasma membrane was discovered by whom and in which year?

Options

A. M. Schleiden , 1839
B. T. Swhwann , 1839
C. Robert Hook, 1838
D. Robert brown, 1839

Answer

To solve the question regarding the discovery of the plasma membrane, we can follow these steps:

### Step 1: Identify the options provided
The options given are:
- A) M. Sheidan in 1839
- B) T. Schwan in 1839
- C) Robert Hooke in 1838
- D) Robert Brown in 1839

### Step 2: Analyze each option
- **M. Sheidan**: He is known for contributing to the cell theory but is not credited with the discovery of the plasma membrane.
- **T. Schwan**: He is recognized for his work in cell theory and is specifically credited with the discovery of the plasma membrane in 1839.
- **Robert Hooke**: He is famous for discovering cells in 1665, but not the plasma membrane.
- **Robert Brown**: He is known for discovering the nucleus in plant cells, not the plasma membrane.

### Step 3: Determine the correct answer
From the analysis, T. Schwan is the scientist who discovered the plasma membrane in 1839. Therefore, the correct answer is:
**B) T. Schwan in 1839**

### Final Answer
The plasma membrane was discovered by T. Schwan in 1839.

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