Which of these organelles synthesizes lipids and carbohydrates?

Answer: the smooth endoplasmic reticulum or SER

Smooth ER. The smooth endoplasmic reticulum (SER) is continuous with the RER but has few or no ribosomes on its cytoplasmic surface. Functions of the SER include synthesis of carbohydrates, lipids, and steroid hormones; detoxification of medications and poisons; and storage of calcium ions