Which side of the Golgi apparatus is known as the receiving side?

The cis face of the Golgi apparatus is recognized as the receiving side because it is the region where newly synthesized proteins and lipids from the endoplasmic reticulum first arrive. This entry point facilitates the processing and modification of these molecules before they are transported to their final destinations. The orientation of the Golgi apparatus is such that the cis face is oriented towards the endoplasmic reticulum, allowing for efficient transport of materials.

On the cis face, enzymes in the Golgi apparatus can add carbohydrate moieties or modify existing molecules, preparing them for their specific roles in the cell. This process is crucial for the proper functioning of many cellular activities, particularly in terms of secretion and delivery of cellular products.

In contrast, the trans face is where the processed materials are sorted and packaged into vesicles for transport to other parts of the cell or outside the cell. The lateral side and terminal face do not represent distinct functional sides associated with the main operational processes of the Golgi apparatus in the same way that the cis and trans faces do.