4-Cell Communication Figs BW

Nak atpase creates ionic concentration gradients 2

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Unformatted text preview: n gradients 2. Membrane selectively permeable to K+ due to open K+ channels ( ) 3. K+ diffuses outward, down concentration gradient 4. Since Na+ and Cl- cannot move to compensate, inside becomes negative 5. K+ diffuses inward, down its electrical gradient 6. System comes to equilibrium when flux of K+ out = flux of K+ in 7. Na+ and Cl- are not in equilibrium 8. Electrochemical gradients (especially for Na+) represent stored potential energy. [K+]o RT 9. Under condition 6, Vm = ln [K+]i zF ion channel are name after the thing that control the pore (where the ion go). 1. ion channel is always gated, but sometimes that gate is always open, in that case, that ion channel is called leakage channel b/c channel is open and ions leaking through. (K+ is responsible for resting potential). 2. if channel have functional gate, then ion channel is called gated-ion channel, name after the thing that control the gating. like voltage, temperature, or binding of ligand (which we're focusing). for a sodium channel on the right, the left...
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This document was uploaded on 03/09/2014 for the course EXSC 301 at USC.

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