Select the mismatch

Options

A. Nucleus - Robert Brown
B. Cell theory - Matthias Schleiden and Theodore Schwann
C. Mesosomes - George Palade
D. Cell membrane - Singer and Nicolson

Answer

To solve the question of selecting the mismatch among the given options, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Option 1: Nucleus - Robert Brown**
- Robert Brown is indeed credited with the discovery of the nucleus in plant cells. This statement is correct.

2. **Option 2: Cell Theory - Matthias Schleiden and Theodor Schwann**
- Matthias Schleiden and Theodor Schwann are known for formulating the cell theory, which states that all living organisms are composed of cells. This statement is also correct.

3. **Option 3: Mesosome - George Palade**
- George Palade is known for his work on ribosomes, not mesosomes. Mesosomes were initially thought to be structures in prokaryotic cells, but they are not universally accepted as true organelles. The discovery of mesosomes is often attributed to other scientists, such as Chapman and Heller. Therefore, this statement is incorrect.

4. **Option 4: Cell Membrane - Singer and Nicholson**
- Singer and Nicholson proposed the fluid mosaic model of the cell membrane, which describes the structure of the cell membrane. This statement is correct.

### Conclusion:
After analyzing all the options, we find that **Option 3 (Mesosome - George Palade)** is the mismatch.

### Final Answer:
The mismatch is **Option 3: Mesosome - George Palade**.

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