Expert: Paras Anand - 10/16/2009

Question
When vesicles from the Golgi apparatus deliver their contents to the exterior of the cell, they add their membranes to the plasma membrane. The plasma membrane does not increase in size, because

Answer
Just as many processes add membrane to the PM, similarly membrane is also taken from the PM and added to the organelles inside the cell e.g. endocytosis. Therefore there is no net increase in PM. This is also required for cell equilibrium.

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