What evidence suggests that proteins are synthesized and modified in the rough ER as opposed to the smooth ER?
A)Ribosomes are associated with the surface of the rough ER.
B)Ribosomes are associated with the surface of the smooth ER.
C)The smooth ER functions in the synthesis of phospholipids.
D)Smooth ER is continuous with rough ER.

Question

Quizplus · Accepted Answer

Ribosomes, which are necessary for protein synthesis, are associated with the surface of the rough ER. They are not associated with the smooth ER, which instead functions in lipid synthesis and detoxification. Therefore, the presence of ribosomes on the rough ER suggests that proteins are synthesized and modified in this organelle.

What Evidence Suggests That Proteins Are Synthesized and Modified in the Rough