1. Plural of ergastoplasm; the basophilic (staining dark with basic dyes) cytoplasmic material in cells, consisting mainly of rough endoplasmic reticulum and ribosomes, involved in protein synthesis.
Usage: technical; biology; cell biology; largely historical term; modern usage favors 'rough endoplasmic reticulum' or 'ribosomes'

Examples

• The ergastoplasms in pancreatic cells are particularly abundant due to high protein synthesis demands.
• Under the electron microscope, ergastoplasms appear as stacked cisternae studded with ribosomes.
• Early cell biologists identified ergastoplasms as the sites of active protein production.
• The concentration of ergastoplasms varies depending on the cell's metabolic activity and protein-secreting function.