Cell Membrane

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The cell membrane enables separation of electrical charge in the body. 

  1. The input of energy to transport ions across the membrane has created an electrical gradient - negative inside and positive on the outside
  2. Active transport of ions across the cell membrane also creates a chemical concentration gradient
  3. Electrical + concentration gradient = electrochemical gradient
  4. Osmotic equilibrium is maintained because water moves freely across the membrane.
Resting membrane potential difference
  1. ECF = 0, ICF = -ve



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