NSCI 301 Exam 1
What does the Na+/K+ ATPase pump?
3 Na+ out, 2 K+ in
What part of a neuron sends information to other neurons?
Axons
Which ion is essential for neurotransmitter release at a synapse?
Ca2+
What makes the lipid bilayer membrane permeable?
Channels and pumps
What are IPSPs usually due to?
Cl- currents from GABA binding
GABA receptors are selective for:
Cl- ions
What is it called when the net driving force for a given ion is zero?
Equilibrium potential
The further an AP gets from the site of stimulation, the smaller the AP gets. True or False
False
Metabotropic receptors are:
G protein-coupled receptors, slow
When a neuron is at rest, is resistance across the membrane high or low
High
How does myelin propagate an AP?
Increased capacitance (ability to store charge)
What tends to happen when neurotransmitter is released into a synapse?
It binds to a receptor on the postsynaptic membrane.
Which ion is responsible for the repolarizing phase of an action potential?
K+ (flows out)
Which ions / molecules are concentrated inside of the cell at rest?
K+, proteins
What is the membrane of a neuron composed of?
Lipid bilayer
Which ion is responsible for the depolarizing phase of an action potential?
Na+ (flows in)
What are EPSPs usually due to?
Na+ currents from glutamate binding
Which ions / molecules are concentrated outside of the cell at rest?
Na+, Cl-
At rest, the inside of a cell is ____ while the outside of the cell is ____ .
Negative, positive.
What is contained within synaptic vesicles?
Neurotransmitters
What can be found in the neuron's cell body?
Organelles
What is responsible for maintaining a cell's resting potential?
The Na+/K+ pump
Spatial summation refers to excitatory input from multiple neurons on one postsynaptic neuron. True or False?
True
Temporal summation refers to excitatory input from one neuron multiple times in a brief period of time
True
What is Ohm's Law?
V=IR I=V/R R=V/I
When a cell is at rest, Na+ has a high ___ and a low ___.
Voltage, current
What is the refractory period of a neuron?
Voltage-gated Na+ channels are closed, cannot refire.
When a membrane reaches threshold, what occurs?
Voltage-gated Na+ channels open
What is myelin?
a mixture of proteins and phospholipids forming a whitish insulating sheath around many nerve fibers, increasing the speed at which impulses are conducted.
Which part of a neuron receives information from other neurons?
dendrites
Cl- entering the cell would:
hyperpolarize the cell
Ionotropic receptors are:
ligand-gated ion channels; fast