What is the primary function of the Golgi apparatus in a cell?

The primary function of the Golgi apparatus in a cell is to modify, sort, and package proteins and lipids. Once proteins and lipids are synthesized in the endoplasmic reticulum (ER), they are transported to the Golgi apparatus, where they undergo further modifications. This can include the addition of carbohydrate groups (glycosylation), phosphorylation, or other chemical changes that are essential for their final functional forms.

After modification, the Golgi apparatus sorts these molecules and packages them into vesicles that are then sent to their specific destinations—this could include secretion outside the cell, delivery to lysosomes, or incorporation into the cell membrane. This processing is crucial for ensuring that proteins and lipids reach the correct locations where they can perform their necessary functions, thereby playing a vital role in maintaining cellular organization and function.