additory contex. . How do absolute and relative refractory periods contribute to the unidirectionality of an action potential? What would happen if a stimulating electrode placed halfway down an axon artificially depolarized a cell above threshold? Would an action potential be stimulated and what direction would it travel, to axon terminal, cell body, or both? Explain

Summation means that a post-synaptic neuron only has an action potential if:     there are no IPSPs     there are no EPSPs     there are more IPSPs than EPSPs     there are more EPSPs than IPSPs

a channel can be gated mechanically, voltage or by a ligand. When you hear a sound all three of these type channels are being utilized. Explain generally where/how each of these channels are being utilized starting from hearing the sound, through travelling down a nerve to transmission to another nerve.

If an axon ([Na+]in = 200 mM) is bathed in solution consisting of [Na+]out = 10 mM, will there be an action potential if a supra-threshold stimulus (changed Vm to -20 mV with opening of Na channels) is injected into the axon?

To fill the blanks choose from the following: Sodium potassium pump, out of, -30, into, -90, potassium gated-channels, active, +30, sodium gated channels, -70, +70, Repolarization , Refractory, Resting Potential, Depolarization, node of Ranvier, Schwann cells, unmyelinated, speed up, slows down, myelinated.

Describe how an action potential in the presynaptic neuron is generated in the postsynaptic neuron. Label the presynaptic neuron, postsynaptic neuron and synapse. Explain what is happening in figure on the left. Use key terms in order AND label on diagram: presynaptic axon terminal, action potential, calcium, vesicle, neurotransmitters, synapse Explain what is happening in the figure on the right. Use key terms in order AND label on diagram: neurotransmitter, postsynaptic receptor, sodium ions, excitatory postsynaptic potential (EPSP), depolarization, action potential, postsynaptic neuron

Distinguish between insulation by oligodendrocyte or Schwann cells. Relate myelination to signal speed.  Describe the myelin-related terms: neurilemma, nodes of Ranvier, internodes, nonmyelinated

rearrange these in the correct order of events in an action potential.

On this motor neuron, Add in and label: dendritic spines an axon collateral, with axon terminals synaptic knobs myelin on the axon and axon collateral synaptic knobs Draw arrows and label: ахon axon terminals synaptic knobs cell body dendrites and dendritic spines And draw an arrow showing the direction the action potential travels.

You have a photoreceptor cell in a dish. You are recording its membrane potential while flashing different intensities of light. Which of the following would you observe? Group of answer choices The cell hyperpolarizes, with brighter light causing more hyperpolarization than dimmer lights The cell depolarizes, with brighter light causing more depolarization than dimmer lights If the light is bright enough to reach threshold, it will fire an action potential No change in membrane potential will be observed