Figure 1 represents a plasma membrane and molecules present on either side. Figure 1.A Model of a plasma membrane demonstrating selective permeability.
Questions: Explain how the model shows selective permeability of the membrane to specific ions.
Describe the characteristics of the phospholipid bilayer that permit small hydrophobic lipid molecules to pass directly across the membrane.
Based on the model, explain whether the molecules shown crossing the membrane require energy to do so.