BIOL 469 Study Guide - Midterm Guide: Barbiturate, G Protein-Coupled Inwardly-Rectifying Potassium Channel, Benzodiazepine
LECTURE 12`
●Conductance in ion channels changes as a function of..?
●Why is it hard to determine the effect of the RMP on channel function?
●Does ion permeability increase or decrease during an AP? Example?
●Outline the Hodgkin + Katz hypothesis
●Write the conductance function
●What problem does the voltage-clamp technique solve? What does the experiment show?
●What kind of current does the voltage-clamp introduce? What kind types of currents can
it measure?
●What does TTX block? What does TEA block? Draw a diagram of the effects on the
currents.
●What 2 things do currents depend on?
●What type of ion is there an influx of with an inward current? What about outward
current?
●What part of the AP is Na+ responsible for? K+? Draw a diagram and label it.
●Write out the steps of depolarization on Na+ channels - activation, deactivation,
inactivation. Give an explanation of inactivation.
●What is the relationship between ion channels, time, and AP firing?
●Which ion channels open at depolarization?
●What is the effect of a larger depolarization on ion channels?
●Which type of ion channel opens faster?
●Explain Na+ and K+ channel responses to prolonged depolarization.
Document Summary
Draw a diagram of the effects on the currents. Write out the steps of depolarization on na+ channels - activation, deactivation, inactivation. Explain na+ and k+ channel responses to prolonged depolarization. Indicate number of subunits, names, transmembrane domains, etc. Compare and contrast chemical and electrical signaling. Write out the table on page 17 of your notes. Compare and contrast direct and indirect signaling. Compare and contrast the nmj with cns synapses. What is bungarotoxin and how is it useful to neurobiologists. Achrs are members of the americ superfamily of ion channels that include also the. A hydrophobicity plot of a membrane protein can be used to . What is the ion selectivity of achrs. The ion selectivity of the nachrs is determined by rings of positively charged amino acids. What do you predict determines the ion selectivity of glycine receptors. Why is it important that pyridostygmine does not cross the blood brain barrier.
