|
Medical Definition of Granular endoplasmic reticulum
1. Endoplasmic reticulum in which ribosomal granules are applied to the cytoplasmic surface of the cisternae; involved in the synthesis and secretion of protein via membrane-bound vesicles to the extracellular space. Synonym: chromidial substance, ergastoplasm, rough-surfaced endoplasmic reticulum. (05 Mar 2000)