by ANS205

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Define nerve impulse
propagation of the action potential along a nerve fiber, way that nerves transmit information
Define resting membrane potential
the cell membrane at rest when it is negative inside the cell (approximately -70mV) and positive outside the cell
What two types of channels help return the cell to resting membrane potential after action potential
non-gated potassium channels and Na-K ATPase pumps
Define depolarization
a change in a cell’s membrane potential which makes it more positive inside the cell and causes propagation of an action potential
Define repolarization
the change in membrane potential that returns the membrane potential to a negative value after the depolarization phase of an action potential
Define hyperpolarization
the change in a cells membrane potential that makes it more negative (opposite of depolarization) due to too many K+ ions flowing out of the cell
Define action potential
short-lasting event in which the electrical membrane potential of a cell rapidly changes due to depolarization. The action potential moves down the membrane in one direction.
Continuous conduction of nerve impulses occurs in _______ axons
In continuous conduction of nerve impulses, the wave of de/repolarization travels from one part of the membrane to the ____ ____ ____
next adjacent part
What are the two types of cells that provide the myelin sheath
oligodendrocytes and Schwann cells
There is _____ for ionic exchange where the myelin sheath is wrapped around the axon
no space
The ___ _ ____ is where ionic exchange occurs
node of ranvier
Action potentials appear to jump/leap between nodes of ranvier, this is known as
salutatory conduction
Axons are protected from drastic ionic fluctuations by the ___ ____
myelin sheath
Where does salutatory conduction occur
myelinated axons
Saltare is a Latin word meaning
to leap
The myelin free regions along the axon are known as
nodes of ranvier
___ and ___ can cause hyperpolarization
Cl- and K+
What is the specialized junction for information exchange between neurons or neuron and another cell
What is the size of a synaptic cleft
one millionth of an inch
What are the two types of synapses
excitatory synapse and inhibitory synapse
Excitatory synapses _____ the postsynaptic neuron
What is EPSP
excitatory postsynaptic potential
A change in the postsynaptic membrane potential produced by excitatory NT is ___
_____ synapses hyperpolarize postsynaptic neurons
IPSP means
inhibitory postsynaptic potential
A change in postsynaptic membrane potential produced by inhibitory NT is __
Name three ways a NT can be removed from neural synapse
enzymes degrading the NT, cell membrane transport system absorbs NT, NT diffuses away from area of synapse
Name two types of synaptic transmission
convergence and divergence
Define convergence transmission
the transmission goes from multiple neurons to fewer and fewer until the info comes together to one neuron (the key neuron)
Define divergence transmission
the action potential is generated on one neuron but has additive effect with action potential to a greater number of neurons
Name three of the most common neurotransmitter components
amino acids, modified amino acids, polypeptides
Where does acetylcholine act
neuromuscular junction
The ____ neurons produce and release ach and can be classified as nicotinic and muscarinic receptors
norepinephrine and epinephrine are produced by ____ neurons and act on ___ receptors
The most predominant inhibitory NT in the CNS (mostly ANS) is
GABA (Y-aminobutyric acid) has a modification at gamma position
Binding to GABA receptor causes _____ (inhibition)
Name three examples of GABA neurotransmitters
sedatives, tranquilizers, muscle relaxants
Glutamate receptors are in high concentration in the ____
brain (memory/learning-cerebral cortex)
____ is the predominant excitatory NT in CNS
Define reflex
automatic response to a stimuli which is perceived by the animal’s body
Define reflex arc
the entire neural circuit from stimulus detection to response
Name an example of a reflex arc
spinal reflex by patellar tendon (knee-jerk)
What are the two types of reflex arcs
spinal reflex, cranial reflex
Eyelids are also known as
x of y cards