What are the respective functions of phospholipids, proteins and carbohydrates of the cell membrane?

Ans) Membrane phospholipids have structural function they produce the bilipid membrane that constitutes the cell membrane itself.

Membrane proteins have various specialized functions. Some of them are channels for substances to pass by the membrane, others are receptors and signalers of information, others are enzymes, others are cell identifiers (cellular labels) and there are still those that participate in the adhesion complexes among cells or between the internal surface of the membrane and the cytosketeleton.

Membrane carbohydrates, associated to proteins or to lipids, are found in the outer surface of the cell membrane and they have in general labeling functions for recognition of the cell by other cells and substances (for example, they differentiate red blood cells in relation to the ABO blood group system), immune modulation functions, pathogen sensitization functions, etc.