what is the fuction of cell wall?

what is murein?

Cell wall is a rigid, protective covering of cells. Function of cell wall is:

• Cell wall functions as apoplast pathway (in apoplast pathway water moves from cell to cell via spaces in the cellulose cell walls until it reaches the endodermis).
• It provides mechanical support.
• It counteracts turgor pressure.
• It provides shape to the cell.
• Cell wall protects against pathogen and mechanical injury.
• It prevents busting of cell on endosmosis.
• The cell wall is semi-permeable. It only allows certain things to come into the cell.
• Cell wall is an important reserve of carbohydrates, which can in dire situations, be used by the cell for other metabolic purposes.

Murein is a peptidoglycan. It is a polymer of disaccharides (glycan) cross-linked by short chains of amino acids (peptide) that forms a mesh-like layer outside the plasma membrane of Archaea bacteria. Murein serves a structural role in the cell wall of bacteria, giving structural strength and rigidity. It also serves to counteract osmotic pressure of the cytoplasm. It is involved in binary fission during bacterial cell reproduction.