Select the wrong statement

Options

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

Explanation

To solve the question of selecting the wrong statement, we will analyze each statement provided in the question step by step.

### Step-by-Step Solution:

1. **Statement 1: Bacterial cell wall is made up of peptidoglycan.**
- **Analysis:** This statement is correct. The bacterial cell wall is primarily composed of peptidoglycan, which is a polymer made of sugar derivatives and amino acids. Peptidoglycan provides structural support to the bacterial cell.

2. **Statement 2: Pili and fimbria are mainly involved in motility of bacterial cells.**
- **Analysis:** This statement is incorrect. While pili and fimbriae are appendages found on bacterial cells, they are not primarily involved in motility. Instead, pili are mainly involved in processes like conjugation (transfer of genetic material), and fimbriae are involved in adhesion to surfaces. The structures responsible for motility in bacteria are flagella.

3. **Statement 3: Cyanobacteria lack flagellated cells.**
- **Analysis:** This statement is correct. Cyanobacteria, which are a group of photosynthetic bacteria, do not have flagella. They can be motile or non-motile, but they do not possess flagella for movement.

4. **Statement 4: Mycoplasma is a wall-less microorganism.**
- **Analysis:** This statement is also correct. Mycoplasma are a group of bacteria that lack a cell wall, making them unique among bacteria. They are indeed the smallest known bacteria and are classified as gram-negative.

### Conclusion:
After analyzing all four statements, the only incorrect statement is **Statement 2: Pili and fimbria are mainly involved in motility of bacterial cells.** The correct structures for motility in bacteria are flagella.

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

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