Mastering A and P: Neurons
__________ receptors are targeted to treat anxiety; __________ receptors are targeted in sleep aids.
BZ; BZ-1
GABA causes the opening of __________.
Chloride channels
Which of the following is NOT something that could happen to the chemical messenger released from a pre-synaptic neuron? a) degradation by enzymes in the synaptic cleft b) binding to receptors on the post-synaptic membrane c) removal by transporters on the pre-synaptic cell membrane d) binding to receptors on the pre-synaptic membrane
D. There are no receptors for these chemical messengers on the pre-synaptic membrane.
The mechanism by which the neurotransmitter is returned to a presynaptic neuron's axon terminal is specific for each neurotransmitter. Which of the following neurotransmitters is broken down by an enzyme before being returned?
Yes, acetylcholine is broken down by acetylcholinesterase before being returned to the presynaptic neuron's axon terminal.
A chemical synapse between an axon terminal and a cell body would be categorized as __________.
axosomatic
When an action potential reaches the axon terminal, a depolarization causes voltage-gated __________ channels to open.
calcium
GABA action is associated with __________.
chemical synapses
Binding of a neurotransmitter to its receptors opens __________ channels on the __________ membrane.
chemically gated; postsynaptic
Binding of the neurotransmitter to its receptor causes the membrane to __________.
either depolarize or hyperpolarize
The chemical messenger at a synapse is released from the pre-synaptic cell by __________.
exocytosis
A high dose of valium will inhibit general IPSP activity in the central nervous system resulting in a possible __________ in the level of anxiety.
increase
A(n) __________ is created when neurotransmitters cause the opening of chloride channels in the post-synaptic neuron.
inhibitory post-synaptic potential (IPSP)
What is the type of membrane potential used by GABA?
inhibitory post-synaptic potential (IPSP)
Valium is a benzodiazepine drug. Valium, at an appropriate low dosage, will increase the affinity of GABA for BZ type GABAA receptors, resulting in opening of chloride channels, thus causing an IPSP. This will provide a general __________ effect in the central nervous system to __________ anxiety.
inhibitory; decrease
A GABAA receptor that causes the opening of ion channels directly is termed a(n) __________ receptor. The channel it opens is _________.
ionotropic; ligand-gated
The opening of sodium channels in a neuron will cause the interior of the cell to become __________, while the opening of chloride channels will cause the interior of the cell to become __________.
more positive; more negative
The chemical messenger that carries information from a pre-synaptic neuron to a post-synaptic neuron is a(n) _____.
neurotransmitter
In a synapse, neurotransmitters are stored in vesicles located in the __________.
presynaptic neuron
An action potential releases neurotransmitter from a neuron by opening which of the following channels?
voltage-gated calcium channels
There are several reasons why alcohol depresses the central nervous system. One reason is that it enhances the actions of GABA at GABAA receptors. However, it appears to __________.
work on an area of the cell membrane and not the actual GABAA receptor
