The most basic difference between RER and SER is the presence of ribosomes. SER stands for Smooth Endoplasmic Reticulum. SER mainly produce and export lipids and protein and function for detoxification, while RER produces, secrete and export proteins and few. The RER is named for the appearance of its outer surface, which is studded. Answer · Difference between smooth and Rough endoplasmic Reticulum (SER/ RER) SER RER 1.