The cell wall of prokaryotes are made up of

(a) Cellulose

(b) Proteins

(c) Peptidoglycan

(d) Protein and fats

Prokaryotes are single-celled organisms whose cells are much smaller than those of eukaryotes. They lack a nucleus and membrane-bound organelles, but their cells are enclosed by a rigid cell wall.

Composition of Prokaryotic Cell Wall

• The wall is made of a large polymer called peptidoglycan (murein).
• Peptidoglycan consists of glycan chains of repeating N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM).
• These glycan chains are cross-linked by peptide side chains.
• The peptides are unique because they contain D-amino acids along with the usual L-amino acids.

This structure provides strength and rigidity to the cell wall and helps maintain the cell’s shape.

Significance of Peptidoglycan

• Structural Role: Surrounds the cytoplasmic membrane, protecting the cell.
• Immune Response: In pathogenic bacteria, peptide fragments can act as antigens, triggering an immune response in the host.
• Variation: The amino acid composition in peptides varies among species, giving diversity to bacterial cell walls.

Comparison with Other Organisms

• Plants: Cell wall is made of cellulose.
• Fungi: Cell wall contains chitin.
• Prokaryotes: Cell wall is made of peptidoglycan.

Correct Option: C. Peptidoglycan