Select the wrong statement

Options

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

Answer

To solve the question "Select the wrong statement," we need to analyze each of the provided statements one by one.

### Step-by-Step Solution:

1. **Evaluate the First Statement:**
- **Statement:** "Bacterial cell wall is made up of peptidoglycan."
- **Analysis:** The bacterial cell wall is indeed composed of peptidoglycan, which is a polymer consisting of sugars and amino acids. This statement is true.

2. **Evaluate the Second Statement:**
- **Statement:** "Pili and fimbri are mainly involved in motility of bacterial cells."
- **Analysis:** Pili and fimbriae are not primarily involved in the motility of bacteria. Instead, they play roles in attachment (fimbriae) and genetic material transfer (sex pili). Therefore, this statement is incorrect.

3. **Evaluate the Third Statement:**
- **Statement:** "Cyanobacteria lack flagellated cells."
- **Analysis:** Cyanobacteria generally do not possess flagella. This statement is true as most cyanobacteria are non-motile.

4. **Evaluate the Fourth Statement:**
- **Statement:** "Mycoplasma is a wall-less microorganism."
- **Analysis:** Mycoplasma are indeed wall-less bacteria, which gives them a unique characteristic of lacking a definite shape. This statement is true.

### Conclusion:
After analyzing all the statements, the only incorrect statement is the second one: "Pili and fimbri are mainly involved in motility of bacterial cells." Thus, the answer is option B.

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