Differentiate between rough and smooth endoplasmic reticulum. How is endoplasmic reticulum important for membrane biogenesis?

(N/A) The ribosomes, which are present in all active cells, are the sites of protein synthesis. Endoplasmic reticulum helps in transporting these proteins to various places. The smooth endoplasmic reticulum helps in the manufacture of fat and lipids, which, along with proteins, help in building the cell membrane, a process known as membrane biogenesis.

Smooth Endoplasmic Reticulum $(SER)$	Rough Endoplasmic Reticulum $(RER)$
$SER$ does not have ribosomal particles on its surface, hence it looks smooth. It helps in the manufacture of lipids and fat molecules.	$RER$ has particles of ribosomes on its surface. Ribosomes are the sites of protein synthesis.