Question

Which component provides rigidity to bacterial cell walls?

• A. \( \text{Cellulose} \)
• B. \( \text{Chitin} \)
• C. \( \text{Peptidoglycan} \)
• D. \( \text{Lipopolysaccharide} \)

Hint:

Penicillin antibiotics work by inhibiting the synthesis of peptidoglycan, causing the bacterial cell wall to weaken and burst.

Answer 1

The Correct Option is C

Concept: The bacterial cell wall is a protective layer that maintains the cell's shape and prevents it from bursting due to osmotic pressure.
• Different organisms use different polymers to build their cell walls.
• Plants use cellulose, while fungi use chitin.

Step 1: Composition of the Bacterial Wall.
Bacterial cell walls are uniquely composed of a polymer called Peptidoglycan (also known as murein). This molecule consists of sugars (NAG and NAM) and amino acids linked together into a mesh-like structure.

Step 2: Rigidity and Strength.
The cross-linking of peptide chains provides immense mechanical strength and rigidity. This rigid framework allows bacteria to survive in various environments with different solute concentrations. Gram-positive bacteria have a very thick layer of peptidoglycan, while Gram-negative bacteria have a thinner layer. Final Answer: Peptidoglycan is the component that provides structural rigidity to bacterial cell walls.