Smooth endoplasmic reticulum
The smooth endoplasmic reticulum is the part of the endoplasmic reticulum (ER) which does not have ribosomes bound to it, thus not exhibiting the bumpy appearance shown by the rough endoplasmic reticulum. It can be found in many cell types and serves different functions in each.
It is from these smooth areas of the ER that vesicles bud off, transporting lipids, steroids and proteins to the Golgi apparatus and other parts of the cell. The majority of cells do not have much smooth ER, but cells that secrete these products for example those in the reproductive organs and skin oil glands have a much larger amount of smooth endoplasmic reticulum. Other functions include metabolism of carbohydrates and steroids, and detoxification of drugs. Smooth ER can also contain enzymes such as glucose-6-phosphotase which is involved in gluconeogenosis.