Answer:
If the cell is exposed to any drug molecule that will inhibit the cell from making its transport proteins to pass through then the cell will be deprived of its essential nutrients also sometimes the cell will build an inbuilt toxicity because of not spitting out the unwanted material out of it.
The plasma membrane is the semi permeable membrane that serves as a gateway, when this gateway is blocked the cell cannot get its vital nutrients and cannot excrete its unnecessary material.