Which of the following is NOT a function of the smooth ER?

Smooth endoplasmic reticulum (smooth ER) has several key functions, including detoxification of drugs, synthesis of glycogen, and gluconeogenesis. It is primarily involved in lipid synthesis and metabolism, storage of calcium ions, and the detoxification of various metabolites and drugs.

The correct answer indicates that translation of RNA to proteins is not a function of the smooth ER. This process occurs in the ribosomes, which can be found freely floating in the cytoplasm or attached to the rough endoplasmic reticulum (rough ER). The rough ER is specifically equipped with ribosomes, making it the site where protein synthesis, or translation, occurs. Therefore, since translation is associated with the rough ER and not the smooth ER, choosing the function associated with the smooth ER reinforces the understanding of cellular structures and their specific roles.