NERVE CELL MEMBRANE Nerve Cell 25 um Up

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NERVE CELL & MEMBRANE

NERVE CELL & MEMBRANE

Nerve Cell 25 um Up to 1 meter Axon Dendrite 1 um Axon Termination

Nerve Cell 25 um Up to 1 meter Axon Dendrite 1 um Axon Termination

Permeable Membrane is permeable to both Na+ & Cl- Na+ Cl중성 Na+ Cl- 중성

Permeable Membrane is permeable to both Na+ & Cl- Na+ Cl중성 Na+ Cl- 중성 항상 전기적으로 중성, 농도가 같아질 때까지 Diffusion만 발생, V=0

Semi-permeable Membrane Semi-persmeable Membrane (Only to Na+) Na+ Cl중성 Na+ Cl- 중성 Dynamic Equilibrium

Semi-permeable Membrane Semi-persmeable Membrane (Only to Na+) Na+ Cl중성 Na+ Cl- 중성 Dynamic Equilibrium

Analysis l 전압의 발생 조건은 ? ü반투막 ( Electric Field 발생 ) ü농도 차

Analysis l 전압의 발생 조건은 ? ü반투막 ( Electric Field 발생 ) ü농도 차 V IF) Scale Down , Random Noise 발생 t

Nernst Equation

Nernst Equation

The Active State Vo Repolarization 1 t=t 1 t D 1 D 2 t=t

The Active State Vo Repolarization 1 t=t 1 t D 1 D 2 t=t 2 Vo 2 Depolarization t 1 Hyperpolarization t 2 t -60 m. V Resting Membrane Potential (RMP) t. D

참고) Micropipet Microelectrode Puller

참고) Micropipet Microelectrode Puller

The Active Potential Vo 20 Membrane conductance (membrane permeability) 0 -20 -40 VTH ;

The Active Potential Vo 20 Membrane conductance (membrane permeability) 0 -20 -40 VTH ; Threshold Voltage 약간 VTH이상으로 올려주면 -60 Na, K의 conductance가 커져서 Depol. Repol. 됨 Abstract Refractory Period 자극이 새로 들어와도 무시 Relative Refractory Period 전의 크기보다 더 큰 자극이 와야 반응. 같은 신호가 짧은 시간에 오면 Saturation

Nerve Conduction Velocity = Nerve Conductance Velocity(NCV) ; 수십 m/s ( 40 m/s, 90

Nerve Conduction Velocity = Nerve Conductance Velocity(NCV) ; 수십 m/s ( 40 m/s, 90 m/s ) t=? 2 m t=0, tickling

Nerve Conduction Velocity Resting Na+ - K+ pump Na+ K+ Na+ Repol. K+ Depol.

Nerve Conduction Velocity Resting Na+ - K+ pump Na+ K+ Na+ Repol. K+ Depol. Na+

Refractory Period Nerve Conduction Velocity NCV ↓ NCV ↑

Refractory Period Nerve Conduction Velocity NCV ↓ NCV ↑

Thank you

Thank you