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10 Cards in this Set
- Front
- Back
What is the resting membrane potential? |
Inside of the cell is -ve charged compared to the outside. This reflects the ion distribution across the cell membrane (across the semi-permeable membrane). |
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What does the cell membrane consist of? Explain what this is? |
Phosopholipid bilayer (look at diagram) This is mechanism to allow substances to go through the channel. |
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Protein |
Inside- many
Outside - few Captive protein molecule account for -ve charge inside the cell. HIGH K+ concentration inside the cell. high concentration of NA+ outside cell. |
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What does the RMP depend on? |
semi-permeable membrane. -60mv is permeable to K+. Why? Negative charged protein holds back some of K+ ions so not all K+ moves. RMP (-60mv) selects the equilibrium of diffusion and electrostatic forces of Potassium. This -60 equal to k+ equilibrium potential. |
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Describe how the NA+/K+ pump works? |
Pumps 3 NA+ out and 2K+ in. Leakage of Na+- high concentration. |
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What is the RMP a result of? |
Selective permeability & NA/K pump. |
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NA+ channels can be opened by? |
Neurotransmitters. Binding of NT to receptor on an ion channel - open/ close the channel. |
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What causes an A.P? |
Opening of voltage-gated NA+ channel at the axon hillock (this requires large EPSP). |
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How does the ion distribution happen? |
1) diffusion of particles = high concentration -> low concentration (moves down concentration gradient). 2) Electrostatic forces (moves down charge gradient) similar chargers repel each other. *opposites attract* |
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End of flash cards |
yayyyy! |