Select the wrong statement

Options

A. Cyanobacteria lack flagellated cells.
B. Mycoplasma is a wall-less microorganism
C. Bacterial cell wall is made up of peptidoglycan
D. Pilli and fimbriae are mainly involved in motility of bacterial cells

Answer

To solve the question of selecting the wrong statement from the given options, we will analyze each statement one by one.

### Step 1: Analyze Option A
- **Statement**: Cyanobacteria lack flagellated cells.
- **Explanation**: Cyanobacteria, also known as blue-green algae, belong to the kingdom Monera and the class Eubacteria. They do not possess flagella, which means they do not have flagellated cells.
- **Verdict**: This statement is **true**.

### Step 2: Analyze Option B
- **Statement**: Mycoplasma is a wall-less microorganism.
- **Explanation**: Mycoplasma is indeed a type of bacteria that does not have a cell wall. It is one of the smallest known living cells.
- **Verdict**: This statement is **true**.

### Step 3: Analyze Option C
- **Statement**: Bacterial cell wall is made up of peptidoglycan.
- **Explanation**: The cell wall of bacteria is primarily composed of peptidoglycan, which is a polymer consisting of sugars and amino acids. This structure is crucial for maintaining the shape and integrity of bacterial cells.
- **Verdict**: This statement is **true**.

### Step 4: Analyze Option D
- **Statement**: Pili and fimbriae are mainly involved in motility of the bacterial cells.
- **Explanation**: Pili and fimbriae are hair-like structures on the surface of bacteria. Their primary functions are not motility but rather attachment to surfaces and gene transfer. They do not provide movement in the same way that flagella do.
- **Verdict**: This statement is **false**.

### Conclusion
After analyzing all the options, we find that the wrong statement is **Option D**.

### Final Answer
The wrong statement is **Option D**: Pili and fimbriae are mainly involved in motility of the bacterial cells.

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