Question

How would a cell be affected if it lost the ability to be selectively permeable?

Answer 1

If there's no selective permeability, the cell would be able to allow all substances into the cell, in other words, the cell will be "permeable".

Normally, the biological membranes have a selective permeability, that is to say, they let themselves through some substances more easily than others, quickly pass through the membrane, because they dissolve in the lipid bilayer.

*Hydrophobic substances rapidly cross the membrane because they dissolve in the lipid bilayer.

*The small polar molecules (like H2O and CO2) thanks to their small size, these polar molecules also cross the double lipid layer.

*Large molecules and ions pass through the membrane through specific transport proteins, such as uniport, symport or antiport.

Answer 2

If a cell lost the ability to be selectively permeable, then the cell wouldn't be able to get the nutrients or things it needs from outside the cell... There's a reason that the cell is selectively permeable (cell selects what it wants in or out of the cell).