MCQs Flashcards
Gray’s Type 1 synapses are ___________ while Gray’s Type 2 synapses are____________.
asymmetric; symmetric
The action potential depends on the presence of extracellular ___________.
sodium
Antagonists of which receptor are used as antiemetics, anxiolytics, and antipsychotics?
5HT3
_________ is actively concentrated inside the cell and __________ outside.
Potassium in, Sodium and Calcium out
________________ is/are an example of a catecholamine neurotransmitter.
DA, NE, Epi
In general, which segment of a GPCR is responsible for specificity of the receptor?
3rd intracellular loop
The neurons of the substantia nigra are ____________ and contain the pigment ___________.
dopaminergic; neuromelanin
_____________ is the major excitatory transmitter in the brain and __________ is the major inhibitory transmitter.
Glutamate and GABA
Hodgkin and Huxley found that the resting membrane potential of the inside versus the outside of the axon is ___________.
-60mV
Endocannabinoids are ___________________.
hydrophobic, retrograde messengers,
found on both GABA and Glutamate nerve endings
What is Neurotensin?
Peptide neurotransmitter that requires calcium to be released.
Muscarinic ACh receptors are both _____
Presynaptic and postsynaptic
In mammals, at membrane potentials negative to –102 mV, K+ ions tend to flow ____ the cell; increasing the membrane conductance to K+ causes the membrane potential to become more ___________.
in; depolarized
Calcium currents ______________.
contribute to electrophysiological processes.
are important for 2nd messenger systems
voltage sensitive
________________ is involved in the enzymatic degradation of catecholamines.
MAO
Of the types of neuroglia, ___________ play a role in nerve growth while ___________ serve immune functions for neurons in the brain.
Astrocytes, microglia
The blood-brain barrier is formed by the encapsulation of ____________ by ___________ which creates selective permeation into the brain tissue.
capillaries; neuroglia
Purinergic receptors are ________ that bind ATP and __________.
GPCRs; adenosine
Which of these ions are permeated through 5HT3 ionotropic receptors?
Na+, K+
The basic structure of a neuron includes a cell body, a variable number of __________, and a single _________.
dendrites; axon
In the periphery, ______________ are the primary immune support for neurons.
Schwann Cells
Cystic fibrosis is caused by a mutation of a ____________ channel.
Chloride
Which part of a neuron is responsible for generating action potential?
axon hillock
Which of the following are important for the Nernst equation?
temperature, ionic concentration outside and inside the cell.
Myelin is synthesized in the periphery by _____________ and in the CNS by ___________.
Schwann cells; oligodendrocytes
The GABAA receptor is ____________ and is selective for __________.
ionotropic; anions
The rate of acetylcholine synthesis is determined by ______________.
choline
Tetraethylammonium (TEA) selectively blocks voltage-dependent _______ currents.
Potassium
Curare works by binding to the postsynaptic receptor for which neurotransmitter?
acetylcholine
In general, GPCRs are comprised of ____________ polypeptide (s) and spans the membrane ________ times.
single, 7
The active zone of a presynaptic neuron contains numerous ______________, and the membrane of this area is densely packed with ______________.
synaptic vesicles; calcium channels
Norepinephrine is converted to epinephrine by ________________.
Phenylethanolamine N-Methyltransferase
The nicotinic receptor, GABAA receptor, and the 5HT3 receptor are all
ionotropic
Protein zero is the primary building block of
peripheral myelin.
Vesicular monoamine transporters are inhibited by _______________.
Reserpine
The ____________ determines the quantity and connections that a neuron makes.
dendritic tree
NOS is activated by ________________.
Ca++ binding to calmodulin
The capillary endothelial cells in the brain contribute to the blood-brain barrier through use of
tight junctions
The ____________ refers to the membrane potential following an action potential that typically becomes more negative than the original value.
after hyper-polarization
Which enzyme that catalyzes monoamine synthesis is found in dopamine neurons?
monoamine oxidase
GABAergic interneurons of the cerebellar and cerebral cortex are fall into which category of neurons?
inhibitory with local contacts
Which of these is a connection between populations of neurons projecting from one brain region to another?
macrocircuit
The synaptic cleft is bounded on one side by the presynaptic ____________ and the other with the postsynaptic _________.
terminal bouton; dendrites
Muscarinic ACh and beta adrenergic receptors are
GPCRs.
Action potentials are produced through an increase in ________ conductance followed by an increase in ________ conductance.
Sodium, potassium
Low threshold calcium currents have a threshold of ________ mV.
- 65
Neurons that spontaneously generate action potentials at low frequencies (1-10 Hz) are associated with ____________.
ACh
NMDA receptors require which of these in order to open their channels?
glutamate binding and depolarization
The nicotinic receptor is selectively permeable to ___________ due to its structure creating a _________ charged pore.
cations, negatively
The brain accounts for _______ percent of the total serotonin found in the body.
1
The membrane potential where there is no net flow of ions is known as ____________.
equilibrium potential
The voltage-sensitive K+ current that regulates the responsiveness of the neuron to depolarizing inputs is known as the _____ current.
m
D1-like receptors _________ adenylate cyclase and D2-like receptors _________ adenylate cyclase.
activate, inhibit
Prozac works by blocking _____________.
DAT and SERT
Neuropeptide receptors are
GPCRs
When a GPCR is activated, it couples to a _____________ initiating the exchange of ______________.
G-protein; GDP for GTP
Dopamine is converted to norepinephrine by ________________.
Dopamine 3-Hydroxylase
Catacholamines are release peripherally by___________________.
Tyramine
Calcium ion permeability of neuronal nicotinic receptors is__________ compared to muscle nicotinic receptors?
higher
Tetrodotoxin (TTX) selectively blocks voltage-dependent _______ currents.
sodium
High threshold calcium channels have ____ homologous domains, each with ____ regions.
four; six
Which of these are excitatory projection neurons?
pyramidal cells
A single GPCR can activate _______ G-protein (s).
many
Acetycholinesterase is responsible for the____________ of acetylcholine.
inactivation
Which of these is a local inhibitory interneuron of the cerebral cortex?
basket cell, double bouquet, chandelier cell
Action potential transmission in myelinated neurons propagates very rapidly due to its ability to ‘leap’ down the axon on the ___________ that occur between ___________.
Nodes of Ranvier; myelin internodes
Glycine receptors are __________ located in the spinal cord and brain stem and are selectively permeable to _________.
inhibitory; calcium ions
Nicotinic receptors open in response to the binding of _____ acetylcholine molecules that produces a conformational change in the _______ subunit.
two; TM2
Desensitization of GPCRs occurs when PKA or PKC _________ sites on the _______ intracellular loop.
phosphorylates; third
High-affinity neuronal reuptake of neurotransmitters requires ______.
Na+ K+ Cl-
The absolute refractory period is mediated by the inactivation of ____channels.
Na+
At normal resting membrane potential, NMDA receptors are blocked by
Mg
