Endoplasmic Reticulum

In eukaryotic cells, the endoplasmic reticulum (ER), a particular type of organelle, creates cisternae, a network of flattened, membrane-enclosed sacs or tube-like structures. The outer nuclear membrane and its membranes are one. With the exception of red blood cells and spermatozoa, all types of eukaryotic cells have endoplasmic reticulum. Endoplasmic reticulum comes in two different varieties: rough and smooth. Ribosomes are found on the rough endoplasmic reticulum's outer face, which is where protein production takes place. Most cells include the rough endoplasmic reticulum, but hepatocytes in particular. The smooth ER performs lipid synthesis and metabolism, steroid hormone generation, and detoxification processes but lacks ribosomes.

For more: endoplasmic reticulum antibody