Biology · Carbohydrates

A cell wall is a layer located outside the cell membrane found in plants, fungi, bacteria. Plant cell is made up of cellulose, fungi cell of chitin and bacteria cell is made up of peptidoglycan. 

Cellulose

• What it is: A polysaccharide composed of β-glucose units.
• Where it's found: Primarily in the cell walls of plants and some algae.
• Function: Provides structural support and rigidity to plant cells, not bacteria.

Chitin

• What it is: A polysaccharide similar to cellulose but contains nitrogen (N-acetylglucosamine units).
• Where it's found: In the exoskeletons of arthropods and the cell walls of fungi.
• Function: Provides strength and protection, but not found in bacterial cell walls.

Fibres

• What they are: Thread-like structures made of various proteins or carbohydrates, depending on their origin.
• Types:
• Plant fibers like cellulose found in cotton, flax.
• Animal fibers like collagen found in tendons, wool.
• Function: Provides strength, flexibility, and structure, but not specific to bacterial cell walls.

Fats (Lipids)

• What they are: A type of lipid used for energy storage, insulation, and forming cell membranes.
• Where they're found: In cell membranes, not part of the cell wall structure.
• Function: Essential for energy storage and insulation but not related to bacterial cell walls.

Peptidoglycan

• What it is: A polymer consisting of sugars and amino acids.
• Where it's found: A critical component of bacterial cell walls, especially in Gram-positive bacteria.
• Function: Provides structural integrity and protection against osmotic pressure.
• Target for antibiotics: Many antibiotics, such as penicillin, target peptidoglycan, disrupting bacterial cell wall synthesis.