Final answer:
Uncoating of COP II vesicles and binding to Golgi are triggered by GTP hydrolysis.
Step-by-step explanation:
For COP II vesicles, uncoating of the vesicles and binding to Golgi are triggered by GTP hydrolysis. When GTP is hydrolyzed to GDP, it provides the energy needed for uncoating and binding of the vesicles to the Golgi. This process allows the cargo proteins to be delivered to their proper destination within the cell.