Some cells with very negative resting membrane potentials, like -80 mV, express an the inward rectifier K+ channel. Describe the channel/ conductance.

Three currents are produced by a 56 mV depolarization leading to an action potential in a squid axon membrane during a voltage clamp experiment as shown. What is the mechanism underlying the capacitive current? 56 mV Depolarization Capacitative current Late current Early current Time (ms) Opening of Na* channels Current due to the Na/K* pump O Neutralization of the charge on the membrane Opening of K channels Membrane Membeane current imA/cm potential (mV)

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What proteins are responsible for membrane potential in section 1 potassium leak channels opening of potassium channels opening of ligand gated sodium channels Na+/K+ Atpase opening of sodium channels

What is the difference between a ligand-gated channel (like H1 or the AChR) and a voltage gated channel?

Part C-Comparing and Contrasting the Two Types of Voltage-Gated lon Channels Sort the phrases into the appropriate bins depending on whether they describe similarities or differences between voltage-gated K* channels and voltage-gated Na+ channels. > View Available Hint(s) Reset Help The polarity of the substances they transport across the membrane The direction of ion movement The stimulus that triggers opening through the channel The placement of the channel protein relative to the membrane The inactivation mechanism Similarities Differences

The membrane potential in animal cells, but not in plants, depends largely on resting K+ channels. How do these channels contribute to the resting membrane potential? Why are these channels considered to be nongated channels? How do these channels achieve selectivity for K+ versus Na+, which is smaller than K+?

Nernst (equilibrium) Potential (mV) - 6.lol 0.07 0.125 D.094 lon Intracellular Extracellular Concentration (mM) Concentration (mM) K* 155 4 Nat 12 145 Ca** 104 1.5 4 120 D) If during the generation of an action potential in the skeletal muscle cell the membrane potential approaches +65 mV, membrane permeability for which ion likely plays a major role in membrane depolarization? Explain your choice.

A neuron has a resting membrane potential of -70 milivolts (mV) and a threshold value of -55 mV. Three synapses on the body of this neuron receive the impulses listed below. hyperpolarisation by 5 mV • depolarisation by 15 mV • depolarisation by 10 mV ENTER THE MEMBRANE POTENTIAL AS A NUMBER WITH + OR - IN FRONT OF IT. The final membrane potential will be mV and this cause an action potential becasue it is v than the

Nervous Tissue electrical and chemical disequilibrium across cell membranes equilibrium potential calculating the equilibrium potential using the Nernst Equation The parameters of the Goldman Equation the reason for a -70mV resting'potential in most excitable cells gated channels particulars Defining depolarization, repolarization and hyperpolarization defining the role for the common ions, (K+, Na+ )special ions Cl, Ca+ have Define Current and ohm's law l=V/R Defining graded potentials and particulars about graded potentials such as subthreshold GP o suprathreshold GP temporal summation spatial summation e1 of 2 418 words English (United States) O Focus B I @ #3 24 & * 3 4 7 8