The composition of cell wall varies in different groups of living organisms. Comment.
GeneralClass 12AllAnswered 27 Mar 2026
Answer
Answer:
Cell wall chemical composition varies across taxonomic groups:
|
Organism |
Cell Wall Composition |
Characteristics |
|
Bacteria |
Peptidoglycan (murein): NAG + NAM + short peptides |
Rigid; target for antibiotics; Gram+ thick, Gram- thin |
|
Fungi |
Chitin (β-1,4-linked N-acetylglucosamine) + glucans |
Tough, flexible; same material as arthropod exoskeletons |
|
Algae |
Cellulose + galactans, mannans, calcium carbonate |
Variable; some with silica (diatoms) or CaCO₃ deposits |
|
Plants |
Cellulose (primary component) + hemicellulose, pectin, lignin (secondary wall) |
Most complex; lignin in woody tissues for rigidity |
Evolutionary significance: Different compositions reflect:
- Habitat adaptations (marine vs terrestrial)
- Mechanical requirements (support, flexibility)
- Phylogenetic relationships
Archaebacterial exception: Lack peptidoglycan; have pseudopeptidoglycan or S-layer proteins
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