Chapter 11 - Nervous System Flashcards
Which of the following structures is not part of the central nervous system:
Brain, nerve, spinal cord, or tract
Nerve
Myelinates nerve fibers in the CNS
astrocyte, ependymal cell, microglial cell, oligodendrocyte
oligodendrocyte
lines brain cavities
astrocyte, ependymal cell, microglial cell, oligodendrocyte
ependymal cell
myelinated nerve fibers in the PNS
microglial cell, oligodendrocyte, satellite cell, schwann cell
schwann cell
CNS phagocyte
astrocyte, ependymal cell, microglial cell, oligodendrocyte
microglial cell
helps regulate the ionic composition of CNS extracellular fluid
astrocyte, ependymal cell, microglial cell, oligodendrocyte
astrocyte
Which of the following is not a function of astrocytes? (a) support and brace neurons, (b) anchor neurons to blood vessels, (c) control the chemical environment around neurons, (d) provide the defense for the CNS.
D
Assume that an EPSP is being generated on the dendritic membrane. Which will occur? (a) specific Na+ channels will open, (b) specific K+ channels will open, (c) a single type of channel
will open, permitting simultaneous flow of Na+ and K+, (d) Na+ channels will open first and then close as K+ channels open.
C
The (a) mechanically gated, (b) voltage-gated, (c) leakage, (d) ligand- gated ion channel opens in response to a change in membrane potential and participates in the generation and conduction of action potentials.
B
Regulation by the nervous system results in reaction to impulses that are (a) fast and long-lasting, (b) fast and short-lived, (c) relatively slow and long-lasting, (d) relatively slow and short-lived.
B
Biogenic amine neurotransmitters include all but (a) norepinephrine, (b) acetylcholine, (c) dopamine, (d) serotonin.
B
The primary function of the (a) efferent neuron, (b) afferent neuron, (c) association neuron, (d) glial cell is connecting other neurons.
C
Inhibition of acetylcholinesterase by poisoning blocks neurotransmission at the neuromuscular junction because
(a) ACh is no longer released by the presynaptic terminal,
(b) ACh synthesis in the presynaptic terminal is blocked, (c) ACh is not degraded, hence prolonged depolarization is enforced on the postsynaptic cell, (d) ACh is blocked from attaching to the postsynaptic ACh receptors.
C
Which of the following neurotransmitters inhibits pain and
is mimicked by morphine, heroin, and methadone?
(a) acetylcholine, (b) endorphin, (c) serotonin, (d) nitric oxide.
B
An IPSP is inhibitory because (a) it hyperpolarizes the postsynaptic membrane, (b) it reduces the amount of neurotransmitter released by the presynaptic terminal,
(c) it prevents calcium ion entry into the presynaptic terminal, (d) it changes the threshold of the neuron.
A
Impulses continue around and around the circuit until one neuron stops firing
converging, diverging, parallel after-discharge, reverberating
reverberating
One or a few inputs ultimately influence large numbers of neurons
converging, diverging, parallel after-discharge, reverberating
diverging
Many neurons influence a few neurons
converging, diverging, parallel after-discharge, reverberating
converging
May be involved in exacting types of mental activity
converging, diverging, parallel after-discharge, reverberating
parallel after-discharge
The ______ is the biosynthetic (and receptive) center of the neuron
cell body
A collection of cell bodies is called a _______ in the CNS and a ___________ in the PNS
nucleus in the CNS, ganglion in the PNS
A bundle of nerve fibers is called a _____ in the CNS and ________ in the PNS
tract in the CNS, nerve in the PNS
Most neurons have many _____, receptive processes that conduct signals from other neurons toward the nerve cell body
dendrites
With few exceptions, all neurons have one _____, which generates and conducts nerve impulses away from the nerve cell body; their terminals release neurotransmitter
axon
________ is a reduction in membrane potential (inside becomes less negative)
depolarization
________ is an increase in membrane potential (inside becomes more negative)
hyperpolarization
____ potentials are small, brief, local changes in membrane potential that act as short-distance signals. The current produced dissipates with distance.
graded or action
graded
_____ potentials, or nerve impulse, is a large, but brief, depolarization signal (and polarity reversal) that underlies long-distance neural communication. It is an all-or-none
phenomenon.
graded or action
action
True or False, APs are independent of stimulus strength
True
True or False, Strong stimuli can cause APs to be generated more frequently but not with greater amplitude
True
A _____ is a functional junction between neurons
Synapse
The information-transmitting neuron is the ______ neuron
presynaptic
