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Na- Phospholipid Bi-layer
(Potasium Ion Channel example) Na- Na- Na- Na- Na- Na- Na- Na- Na- Na- Na- Na- Na- Na- Na- Na- Na- Na- Na- Na- Cytoplasm Sodium Ion
Channel
Potassium Ion
Channel Na- Na- Na- K+ K+ K+ K+ K+ K+ K+ K+ K+ K+ K+ K+ K+ K+ K+ K+ Na- Na- Phospholipid 3 C C CH CH2 CH CH2 CH2 CH2 CH2 O CH2 CH CH2 O CH2 CH2 O O O P CH2 CH2 CH2 CH2 CH3 CH3 CH2 CH2 CH2 O O N(CH2) O K+ K+