Which of the following is least likely to be part of a cell

Which of the following is least likely to be part of a cell membrane? Which of the following is least likely to be part of a cell membrane? transport proteins glycoproteins peptidoglycans enzymes phospholipids

Solution

Peptidoglycans are least likely to be a part of cell membrane.

Plasma membrane consists of a phospholipid bilayer studded with proteins,polysaccharides,lipids.The plasma membrane is a phospholipid bilayer that surrounds every cell and therefore represents the surface of all cells.The membrane is made of lipids which have hydrophobic (water-hating) and hydrophilic (water-loving) regions.

Glycoproteins are integral membrane proteins.They have short carbohydrate chains covalently attached which are exposed on the outer surface of the cell.Integral proteins are those which penetrate the hydrophobic region of the plasma membrane.Glycoproteins play a crucial part in cell-cell recognition.

Transport proteins are transmembrane proteins that provide hydrophilic channels through the membrane to allow specific substances in and out of the cell.

Peptidoglycan forms a mesh-like layer outside the plasma membrane of most bacteria, forming the cell wall.Peptidoglycan serves a structural role in the bacterial cell wall,giving structural strength,as well as counteracting the osmotic pressure of the cytoplasm.