Multiple choice What is the difference between SER and RER? Antolysis Presence of DNA Presence of RNA Presence of ribosomes Reveal answer Fill a bubble to check yourself D Correct answer Explanation Rough endoplasmic reticulum (RER) is studded with ribosomes on its surface, which gives it a rough appearance and makes it active in protein synthesis. Smooth endoplasmic reticulum (SER) lacks ribosomes.