- If action at Axon A that synapses onto Axon B resulted in an increase in dopamine release in the postsynaptic cell, this would be considered __________.A) presynaptic inhibitionB) postsynaptic inhibitionC) presynaptic facilitationD) postsynaptic facilitation
- If a bowling ball fell on your foot, the action potentials would differ from those fired after a feather fell on your foot. The action potentials for the bowling ball would be __________.A) larger in size and faster in occurrenceB) the same size as for the feather but they would be slower in occurrenceC) the same size as for the feather but they would be faster in occurrenceD) smaller in size and faster in occurrence
- Comparing a feather in the left hand with a full lunchbox in the right, __________.A) the action potentials received would be the same in frequency but the action potentials for the lunchbox would increase in amplitudeB) the action potentials received would be the same in frequency but the action potentials for the lunchbox would show variable amplitudeC) the frequency of action potentials would increase for the lunchboxD) the frequency of action potentials would decrease for the feather
- Which of the following ion channel events will produce an EPSP?A) opening a sodium channelB) closing a sodium channelC) opening a potassium channelD) opening a manganese channel
- Which pairing of postsynaptic potential effect with ion channel action is correct?A) ionotropic; direct opening of an ion channelB) ionotropic; more time required to open an ion channelC) ionotropic; G-protein activation leads to activation of a second messengerD) metabotropic; second messenger effects that are specific to neuronal communication
- Axoaxonic synapses differ from axodendritic synapses in that __________.A) they alter the intracellular fluid composition of the neighboring cellB) they can alter the function of the neighboring cell by reducing or increasing the release of neurotransmitterC) axoaxonic synapses alter the neurotransmitter production of both pre- and postsynaptic cellsD) axodendritic synapses alter the neurotransmitter production of both pre- and postsynaptic cells
- A drug that inactivates AChE would be expected to __________.A) prolong the effects of ACh in the synapseB) terminate the effects of ACh in the synapseC) speed up the synthesis of AChD) impair the synthesis of ACh
- Which pairing of receptor type and action is correct?A) ionotropic; direct opening of an ion channelB) ionotropic; more time required to open an ion channelC) ionotropic; G-protein activation leads to activation of a second messengerD) metabotropic; second messenger effects that are specific to neuronal communication
- A key advantage of saltatory conduction is that __________.A) more sodium ions have to be pumped out of the cell after an action potentialB) less transmitter is required to send a message across the next synapseC) myelin speeds up the velocity at which an axon can conduct an action potentialD) myelin requires that nerve cell axons be larger in order to rapidly conduct a signal
- Which statement is true of synapses?A) Action potentials open chloride channels to release neurotransmitters.B) Presynaptic voltage changes past threshold trigger the release of neurotransmitters.C) The interior of the nerve cell becomes more negative during the action potential.D) The exterior of the nerve cell becomes more positive during the action potential.
- Neuronal signals are carried across the synapse by __________.A) direct electrical connections between the two cellsB) the secretion of transmitter molecules into the synapseC) the transfer of ions from one cell to anotherD) an inhibitory effect of a transmitter molecule on the postsynaptic membrane
- Action potentials are generated at the __________ and are conducted along the __________.A) axon hillock; axonB) axon hillock; glial membraneC) terminal buttons; dendriteD) axon; terminal buttons
- Which statement is true of ion distribution across the axon membrane?A) Sodium ions are concentrated outside the axon membrane.B) Potassium ions are concentrated outside the axon membrane.C) Chloride ions are concentrated inside the axon membrane.D) Sodium ions are concentrated inside the axon membrane.
- Which statement is true about vesicles?A) Most terminal buttons contain only a few hundred vesicles.B) Vesicles are located in the postsynaptic dendrites.C) A single terminal button can contain up to a million vesicles.D) Vesicles are found in greatest concentration in the periphery of the terminal button.
- A key event for the release of neurotransmitter from the presynaptic membrane is the __________.A) hyperpolarization of the axon membraneB) arrival of an action potential at the axon terminalC) influx of potassium ions into the axon terminalD) activation of the sodium-potassium pump
- Which statement is true of an action potential?A) The sodium channels are opened at a lower voltage than are potassium channels.B) An action potential requires 5 msec for completion.C) During an action potential, the interior becomes even more negative.D) The potassium channels are opened at a lower voltage than are sodium channels.
- Ions enter and leave the membrane of a myelinated axon at the __________.A) terminal buttonsB) axon hillockC) nodes of RanvierD) release zone
- Which statement is true of receptors?A) The effects of hormones do not involve receptor activation.B) Neurotransmitters act on binding sites on receptors to exert their effects.C) Receptors are insensitive to drugs.D) Neuromodulators are ligands that come from outside the body.
- The force of __________ moves potassium ions __________ the axon.A) diffusion; intoB) retrograde transport; out ofC) electrostatic pressure; intoD) electrostatic pressure; out of
- Which statement is true of the sodium-potassium pump?A) More potassium ions are removed than sodium ions brought in.B) More sodium ions are removed than potassium ions brought in.C) More potassium ions are brought in than sodium ions removed.D) More sodium ions are brought in than potassium ions removed.