The plasma membrane acts as a barrier in cells of all types to control the movement of substances into and out of the cell.
a.explain how the plasma membrane acts as a semi-permeable barrier to various types of molecules based on its molecular structure.
b.describe, in detail, three ways in which large molecules such as proteins can cross the plasma membrane.
A) plasma membranes are made up of phospholipid bilayer. They contain hydrophilic heads and hydrophobic tails. This means only lipid soluble substance will be able to pass through the plasma membrane.
