Correct me if I'm wrong but I believe it is the Gravity (or Gravitational Pull) from the Sun.
Vesicles transport newly synthesized proteins to the Golgi apparatus. After the Golgi apparatus modifies the proteins, vesicles transport the modified proteins to the cell membrane, where they are released.
Hope this helps!
-Payshence
It is needed by all living things and every living cell to carry out life processes, such as breaking down and building up molecules, and transporting many molecules across cell membranes. The form of energy that living things need for these processes is chemical energy, and it comes from food.
