Q: Why do you think that a barrier against the outside environment (such as the lipid membrane that probably formed around early cells) is important to the origins of life?

Flexi Says: The plasma membrane (also called the cell membrane) is a lipid bilayer that is common to all living cells. The plasma membrane forms a barrier between the cytoplasm and the environment outside the cell. A main characteristic of the plasma membrane is selective permeability that has control over what molecules or ions can enter or leave the cell.