CHAPTER 3 TEST Flashcards
dendrites
bushy branching extensions of a neuron that receive messages and conduct impulses toward the cell body
parts of a motor neuron
cell body, dendrites, axon, neural impulse, terminal branches of axon, myelin sheath
a neural impulse will increase in speed if covered by a
myelin sheath
causes of multiple sclerosis
if the myelin sheath degenerates: communication to muscles slows, with eventual loss of muscle control
when is a neuron’s reaction an all or none response
once action potential is released, the axon either fires or it doesn’t
special junctions where impulses are chemically transmitted
synapses
endorphins
natural, opiatelike neurotransmitters linked to pain control and to pleasure.
help explain good feelings such as the “runner’s high,” the painkilling effects of acupuncture, and the indifference to pain in some severely injured people. But once again, new knowledge led to new questions
what neurotransmitter’s decline causes Alzheimer’s
Acetylcholine (ACh)
antagonists
bind to receptors, effect is instead to block a neurotransmitter’s functioning
nervous system
the body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems
axons
the extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands
brain
key communicator for the CNS
pons
in brainstem and coordinates movements
provides link w/ nervous system and endocrine system
hypothalamus or pituitary gland??
controls voluntary movements
motor cortex
apply scenario involving direct stimulation of the motor cortex
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