[system of cisternae in the cytoplasm of many cells; in places the endoplasmic reticulum is continuous with the plasma membrane or outer membrane of the nuclear envelope; rough endoplasmic reticulum membranes are coated with ribosomes and are involved in protein synthesis and transport; smooth endoplasmic reticulum is involved in steroid synthesis. ( CSP )]
UMLS (CSP) C0014239 Relation/PAR: intracellular membrane