Final answer:
Plasma membrane proteins reach the plasma membrane through a targeted variation of endocytosis that utilizes receptor proteins on the plasma membrane.
Step-by-step explanation:
Plasma membrane proteins reach the plasma membrane through the process of endocytosis, specifically via a targeted variation of endocytosis that utilizes receptor proteins on the plasma membrane. These receptor proteins have a specific binding affinity for certain substances and facilitate the movement of the substances into the cell. Once inside the cell, the proteins can then be transported to the plasma membrane through vesicle trafficking.