BoardVitals Microbiology Practice Test

Peptidoglycan plays a crucial role in providing protection and structural integrity to bacterial cells. It is a complex polymer composed of sugars and amino acids that forms a rigid mesh-like structure, known as the cell wall, surrounding the bacterial cell membrane. This structure is essential for maintaining cell shape and resisting osmotic pressure, allowing bacteria to survive in various environments.

Without peptidoglycan, bacteria would be susceptible to lysis (bursting) when exposed to hypotonic solutions, where water would flow into the cell. The rigid cell wall formed by peptidoglycan acts as a barrier that protects the cell from mechanical stress and environmental insults. Additionally, it plays an important role in determining the specific shape of the bacterium, whether it be coccoid, bacillary, or spiral.

The other options do not accurately describe the primary function of peptidoglycan. It is not involved in energy production, DNA storage, or protein synthesis, as these functions are carried out by other cellular components and systems within the bacterial cell.