What is the primary function of the Golgi apparatus?

The primary function of the Golgi apparatus is the modification, sorting, and packaging of proteins. This organelle is often described as the cell's "post office," receiving proteins and lipids from the endoplasmic reticulum, modifying them, and then directing them to their appropriate destinations, either inside or outside the cell.

Within the Golgi apparatus, carbohydrates may be added to proteins (glycosylation), which is important for their stability and function. Additionally, proteins are sorted based on their destination; for example, some may be packaged into vesicles to be delivered to the plasma membrane for secretion, while others may be sent to lysosomes for degradation. This critical role in processing and dispatching proteins makes the Golgi apparatus essential for maintaining cellular function and facilitating communication and transport within the cell.