Where do the lipids and proteins constituting the cell membrane get synthesised?
Explanation Lipids make up the building block of various constituent of cell parts. It is only soluble in non-polar solvents and is synthesized by the Smooth Endoplasmic Reticulum (SER). The SER are devoid of any ribosomes and thereby, making the surface smooth of endoplasmic reticulum. Proteins are macromolecules formed by the condensation of various amino acids. Though, protein synthesis occurs in the ribosomes present freely in the cytosol and in the ribosomes attached to the surface of rough endoplasmic reticulum (RER). But the proteins constituting the cell membrane are synthesized by the RER. RER has ribosomal units attached to their surface which helps in the protein synthesis. The proteins and lipids after synthesis from rough and smooth endoplasmic reticulum respectively are then targeted to the site of action. The mode of targeting to site of action is common in the Golgi-bodies. Packaging and modification of proteins and lipids takes place in the Golgi-bodies and with the help of specific sequence they are sent to the site of action i.e. cell membrane in this case. Final Answer Proteins and lipids are synthesized in Rough Endoplasmic Reticulum (RER) and Smooth Endoplasmic Reticulum (SER) respectively.
