Neurons, Glia, and Methods
Resting Membrane Potential
Action Potential
Synaptic Transmission
Neurotransmitter Systems
100
Information in a neuron travels _________ directionally.
uni (in one direction)
100
This structure on the neuronal membrane moves 2 K+ ions inside the cell and 3 Na+ outside of the cell
Sodium Potassium Pump
100
If Na+ channels were inactivated for less time, _______ would increase.
# of fired action potentials within a set timeframe
100
A neurotransmitter activates a receptor that works through G proteins, producing a slower response with several possible effects inside the cell. What type of receptor is this?
A metabotropic receptor (G protein-coupled receptor, or GPCR)
100
Benzodiazepines act on which neurotransmitter system?
The GABA system.
200
How many neurons and glia are estimated to be in the brain?
85 billion neurons, 85 billion glia
200
True or False
In the Nernst equation,
E_(ion)
represents the average of all ions’ equilibrium potentials
In the Nernst equation, E sub ion represents the equilibrium potential for a single specific ion — not the average of all ions.
200
The hyperpolarization phase of the action potential is due to what?
Prolonged opening of the voltage-gated K+ Channels
200
The ion that triggers the fusion of synaptic vesicles with the presynaptic membrane
Calcium (intracellular)
200
This is the primary excitatory neurotransmitter in the brain
Glutamate
300
Which method should be used to localize specific mRNA transcripts involved in neurotransmitter transport:
in situ hybridization
300
If internal concentration of Cl- was increased from 20mM to 60mM and the external concentration is 150mM which equation would be used to calculate the resulting resting membrane potential?
Goldman Equation
When you're trying to calculate the resting membrane potential and you’re considering more than one ion, such as Na⁺, K⁺, and Cl⁻, you need to use the Goldman equation
300
________ is an inflammatory disease that disrupts action potential propagation. This disruption is caused by __________
Multiple Sclerosis; immune attack on myelin
300
The point labeled A in the figure, when action potentials arrived from the same input sequentially, is an example of what?
Temporal Summation
300
To test how dopamine neurons affect behavior, a researcher uses ____ to selectively target these neurons and ____ to activate them with light.
Cre/lox technology; optogenetics
400
A glial cell that myelinates neurons in the peripheral nervous system
Schwann Cells
400
Why is it necessary to use two electrodes when measuring membrane potential?
Because membrane potential is the difference in charge across the cell membrane, requiring a comparison of inside vs. outside voltages
400
How does the presence of venom affect action potential firing in pain sensing neurons for each species?
In M. musculus, venom increases action potential firing in pain sensing neurons.
In O. torridus, venom decreases action potential firing in pain sensing neurons.
400
At ___ ___, ___ current is transferred between two neurons via protein clusters known as ____.
Gap junctions, ionic current, connexons
400
A) DBH is a precursor enzyme for ____ neurons
B) ___ is the NT implicated with attention
NE, NE
500
__________ is used to study the expression of messenger RNA, non-coding RNA, and other RNA produced by a cell
transcriptomics
500
Suppose the concentration of K+ inside the neuron is 100mM and 10mM outside the neuron. The concentration of Na+ inside the cell is 0mM and outside the cell is 100mM outside. If the membrane is 10 times more permeable to K+ than Na+, what is the resting membrane potential of the neuron?
-43.1 mV
500
Consider the experimental data shown. Based on the internode length and axon diameter, which cell do you predict has a slower action potential conduction velocity, and why?
SBC neurons have decreased axonal diameter and internode length so their conduction velocity will be the slowest.
500
Drug XYZ acts on the neuronal membrane and inactivates potassium channels temporarily, preventing them from opening. What effect would this have on the dendritic length constant?
An increase in dendrite length constant
500
___ is the receptor that endocannabinoids bind to on the ____ terminal, resembling retrograde signaling.
CB1, presynaptic terminal