Smooth endoplasmic reticulum (sER) consists of an irregular network of membranous tubes and vesicles lacking ribosomes.

Regions of sER in different cells have diverse functions, but one of the most important functions in most cells is lipid synthesis.

• For this reason sER is abundant in steroid-secreting cells of endocrine tissues.
• Having no associated RNA and little associated protein, sER stains very poorly with routine LM stains and the cytoplasm of cells rich in sER often appears “empty”.

List 3 functions associated with the smooth ER.

The golgi apparatus.