Respuesta :

cell has cell membrane (also known as the plasma membrane or cytoplasmic membrane) it is a biological membrane that separates the interior of all cells from the outside environment. The cell membrane is selectively permeable to ions and organic moleculesand controls the movement of substances in and out of cells.The basic function of the cell membrane is to protect the cell from its surroundings.

     Well, first, we need to know the structures of a cell to answer this question properly.

      As you may know, a cell contains lots of different structures with different functions, for example, a ribosome, it is an organelle that makes protein for your body. The inside of a cell is separated then by a plasma membrane made out of phospholipids, it protects the inside of a cell by deciding what gets in and what gets out through proteins attached to it and vesicles. The inside of a cell must be always separated from its environment because of the difference in pH levels most of the times, or even to maintain its functions working properly without outside influences.