How does the structure of a lipid influence the lipids function

Lipids that serve as the structural basis for our phospholipid membrane layer are structurally very tightly packed. For that reason they are very "strict" on who they allow through their membrane. A characteristic of the phospholipid bilayer is called selective-permeability, this means it selectively lets certain compounds; ions cross, while others aren't able to cross through it. 

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