Which Organelle is NOT a Part of the Endomembrane System

Question

Which organelle is NOT a part of the endomembrane system?
A) the endoplasmic reticulum
B) the lysosome
C) the nucleolus
D) the Golgi complex

Accepted Answer

The nucleolus is not part of the endomembrane system. The endomembrane system includes the endoplasmic reticulum, lysosomes, and the Golgi complex, among others, and is involved in the synthesis, modification, and transport of proteins and lipids. The nucleolus, however, is involved in ribosome production and is not considered part of this system.