<P> The endoplasmic reticulum ( ER ) is a type of organelle found in eukaryotic cells that forms an interconnected network of flattened , membrane - enclosed sacs or tube - like structures known as cisternae . The membranes of the ER are continuous with the outer nuclear membrane . The endoplasmic reticulum occurs in most types of eukaryotic cells , but is absent from red blood cells and spermatozoa . There are two types of endoplasmic reticulum : rough and smooth . The outer ( cytosolic ) face of the rough endoplasmic reticulum is studded with ribosomes that are the sites of protein synthesis . The rough endoplasmic reticulum is especially prominent in cells such as hepatocytes . The smooth endoplasmic reticulum lacks ribosomes and functions in lipid manufacture and metabolism , the production of steroid hormones , and detoxification . The smooth ER is especially abundant in mammalian liver and gonad cells . The lacy membranes of the endoplasmic reticulum were first seen in 1945 using electron microscopy . </P>
<P> The endoplasmic reticulum ( ER ) is a type of organelle found in eukaryotic cells that forms an interconnected network of flattened , membrane - enclosed sacs or tube - like structures known as cisternae . The membranes of the ER are continuous with the outer nuclear membrane . The endoplasmic reticulum occurs in most types of eukaryotic cells , but is absent from red blood cells and spermatozoa . There are two types of endoplasmic reticulum : rough and smooth . The outer ( cytosolic ) face of the rough endoplasmic reticulum is studded with ribosomes that are the sites of protein synthesis . The rough endoplasmic reticulum is especially prominent in cells such as hepatocytes . The smooth endoplasmic reticulum lacks ribosomes and functions in lipid manufacture and metabolism , the production of steroid hormones , and detoxification . The smooth ER is especially abundant in mammalian liver and gonad cells . The lacy membranes of the endoplasmic reticulum were first seen in 1945 using electron microscopy . </P>
what is the location of smooth endoplasmic reticulum
what is the location of smooth endoplasmic reticulum
found in eukaryotic cells
found in eukaryotic cells