Chapter 11 Flashcards
A system that rapidly communicates information throughout the body; composed of the brain, spinal cord, nerves, and ganglia.
Nervous System
The brain and spinal cord.
CNS
Part of the central nervous system; extends from the brain stem through the vertebrae.
Spinal Cord
The parts of the nervous system outside of the brain and spinal cord; composed of nerves and ganglia.
PNS
A rope-like organ that transfers information to the central nervous system.
Nerve
A mass of nerve cells in the peripheral nervous system that resembles a knot.
plural ganglia
Part of the peripheral nervous system that receives sensory information
Sensory receptor
Any organ that secretes fluids.
gland
An agent that causes a response or a physiological change.
plural stimuli
The ability of an organism to maintain relatively stable internal conditions while external conditions change.
homeostasis
The outer boundary of a cell that is selectively permeable.
plasma membrane
A signal sent by the nervous system when there is a change in electrical charge between two points.
electric signal
The strength of a stimulus is communicated through
Select one:
a. changes in the magnitude of the action potential.
b. the frequency of the action potentials.
c. the length of time action potentials are produced.
d. both the frequency and the length of time action potentials are produced.
d. both the frequency and the length of time action potentials are produced.
When a neurotransmitter binds to its receptor and increases the permeability of the postsynaptic membrane to sodium ions,
Select one:
a. the membrane will be hyperpolarized.
b. more chloride ions will also diffuse into the cell.
c. an excitatory postsynaptic potential (EPSP) will result.
d. the membrane will become impermeable to potassium ions.
e. the sodium ions diffuse out of the cell.
c. an excitatory postsynaptic potential (EPSP) will result.
Saltatory conduction of an action potential means that
Select one:
a. once one action potential is created, it moves down the axon.
b. the whole axon depolarizes at the same time.
c. one action potential stimulates the production of a new action potential at the adjacent site.
d. an action potential is conducted from one node of Ranvier to the next node.
d. an action potential is conducted from one node of Ranvier to the next node.
Which of the following is responsible for problem-solving skills?
Select one:
a. central nervous system
b. peripheral nervous system
c. somatic nervous system
d. autonomic nervous system
e. None of these choices is correct.
a. central nervous system
Each voltage-gated Na+ ion channel has two voltage sensitive gates: an activation gate and an inactivation gate. Which of the following would occur during depolarization?
Select one:
a. Activation gates are open; inactivation gates are closed.
b. Activation gates are closed; inactivation gates are open.
c. Both activation and inactivation gates are open.
d. Both activation and inactivation gates are closed.
e. None of these events occurs during depolarization.
c. Both activation and inactivation gates are open.
When a neuron releases a neuromodulator that _____ the release of neurotransmitters from another neuron, this is called presynaptic facilitation.
Select one:
a. facilitation
b. inhibition
c. summation
d. divergence
e. convergence
a. facilitation
Suppose both excitatory and inhibitory neurons synapse with a single postsynaptic neuron. What determines if an action potential is initiated in the postsynaptic neuron?
Select one:
a. the kind of neuron involved
b. the size of the neuron involved
c. whether the neuron is myelinated or non-myelinated
d. the number of EPSPs in relation to the number of IPSPs
e. This situation is not possible in humans.
d. the number of EPSPs in relation to the number of IPSPs
Which of the following is mismatched?
Select one:
a. microglia - provide support for the neuron cell body
b. astrocytes - blood-brain barrier
c. oligodendrocytes - form myelin sheaths
d. ependymal cells - produce cerebrospinal fluid
e. ependymal cells - choroid plexus
a. microglia - provide support for the neuron cell body
Axons contain
Select one:
a. the trigger zone.
b. foot processes.
c. Nissl bodies.
d. the soma.
e. the rough endoplasmic reticulum.
a. the trigger zone.
The junction of a neuron with another cell is a/an
Select one:
a. synapse.
b. ganglion.
c. receptor.
d. effector.
a. synapse.
A
voltage-gated calcium channel
B
Synaptic Vesicle
C
Presynaptic Terminal
D
Synaptic Cleft
E
Postsynaptic membrane
A
dendrites
B
Neuron cell body (soma)
C
axon
D
Schwann Cell
E
Node of ranvier
LouAnn is being treated for a neurological condition with a specific drug that target neurons deep within the brain. Which glial cell must be bypassed by this drug in order for it to be effective?
Select one:
a. astrocyte
b. microglial cell
c. oligodendrocyte
d. ependymal cell
e. macrophage
a. astrocyte
A neuron that conducts pain sensations to the central nervous system would be classified as a(n)
Select one:
a. motor neuron.
b. sensory or afferent neuron.
c. efferent neuron.
d. association neuron.
e. interneuron.
b. sensory or afferent neuron.
The central nervous system
Select one:
a. is the site for processing information.
b. initiates visual and auditory stimuli.
c. consists of 43 pairs of nerves.
d. is totally involuntary.
e. does not interact with the peripheral nervous system.
a. is the site for processing information.
Hydrocephaly is a condition whereby cerebrospinal fluid accumulates around the brain. What supportive cells continue CSF production despite it backing up in the subarachnoid space?
Select one:
a. astrocytes
b. microglial cells
c. oligodendrocytes
d. macrophages
e. ependymal cells
e. ependymal cells
Cell bodies of the peripheral nervous system are located in
Select one:
a. ganglia.
b. Schwann cells.
c. the motor division.
d. the sensory division.
e. nerves.
a. ganglia.
There are _____ pairs of cranial nerves and _____ pairs of spinal nerves.
Select one:
a. 10; 30
b. 31; 12
c. 12; 31
d. 30; 10
e. 12; 32
c. 12; 31
Digestion of food is regulated by the
Select one:
a. sensory division.
b. sympathetic division of the ANS.
c. parasympathetic division of the ANS.
d. somatic nervous system.
e. None of these choices are correct.
c. parasympathetic division of the ANS.
The enteric nervous system consists of plexuses within the walls of the
Select one:
a. brain.
b. spinal cord.
c. digestive tract.
d. urinary bladder.
c. digestive tract.
The part of the nervous system that controls smooth muscle, cardiac muscle, and glands is the
somatic nervous system.
autonomic nervous system.
skeletal division.
sensory division.
autonomic nervous system.
Motor neurons and interneurons are _____ neurons.
pseudo-unipolar
bipolar
multipolar
afferent
multipolar
Cells found in the choroid plexuses that secrete cerebrospinal fluid are
astrocytes.
microglia.
ependymal cells.
oligodendrocytes.
Schwann cells.
ependymal cells.
Glial cells that are phagocytic within the central nervous system are
oligodendrocytes.
microglia.
ependymal cells.
astrocytes.
Schwann cells.
microglia.
Action potentials are conducted more rapidly
in small-diameter axons than in large-diameter axons.
in unmyelinated axons than in myelinated axons.
along axons that have nodes of Ranvier.
All of these are correct.
along axons that have nodes of Ranvier.
Clusters of neuron cell bodies within the peripheral nervous system are
ganglia.
fascicles.
nuclei.
laminae.
ganglia.
Gray matter contains primarily
myelinated fibers.
neuron cell bodies.
Schwann cells.
oligodendrocytes.
neuron cell bodies.
Concerning concentration differences across the plasma membrane, there is
more K+ and Na+ outside the cell than inside.
more K+ and Na+ inside the cell than outside.
more K+ outside the cell than inside and more Na+ inside the cell than outside.
more K+ inside the cell than outside and more Na+ outside the cell than inside.
more K+ inside the cell than outside and more Na+ outside the cell than inside.
Compared with the inside of the resting plasma membrane, the outside surface of the membrane is
positively charged.
electrically neutral.
negatively charged.
continuously reversing, so that it is positive one second and negative the next.
negatively charged whenever the sodium-potassium pump is operating.
positively charged.
Leak ion channels
open in response to small voltage changes.
open when a chemical signal binds to its receptor.
are responsible for the ion permeability of the resting plasma membrane.
allow substances to move into the cell but not out.
All of these are correct.
are responsible for the ion permeability of the resting plasma membrane.
The resting membrane potential results when the tendency for _______ to diffuse out of the cell is balanced by its attraction to opposite charges inside the cell.
Na+
K+
Cl−
negatively charged protein
K+
If the permeability of the plasma membrane to K+ increases, the resting membrane potential difference ________ . This is called ________.
increases, hyperpolarization
increases, depolarization
decreases, hyperpolarization
decreases, depolarization
increases, hyperpolarization
Decreasing the extracellular concentration of K+ affects the resting membrane potential by causing
hyperpolarization.
depolarization.
no change.
hyperpolarization.
Which of these terms is correctly matched with its definition or description?
depolarization: membrane potential becomes more negative
hyperpolarization: membrane potential becomes more negative
hypopolarization: membrane potential becomes more negative
hyperpolarization: membrane potential becomes more negative
Which of these statements about ion movement through the plasma membrane is true?
Movement of Na+ out of the cell requires energy (ATP).
When Ca2+ binds to proteins in ion channels, the diffusion of Na+ into the cell is inhibited.
Specific ion channels regulate the diffusion of Na+ through the plasma membrane.
All of these are true.
All of these are true.
The major function of the sodium-potassium pump is to
-pump Na+ into and K+ out of the cell.
-generate the resting membrane potential.
-maintain the concentration gradients of Na+ and K+ across the plasma membrane.
-oppose any tendency of the cell to undergo hyperpolarization.
maintain the concentration gradients of Na+ and K+ across the plasma membrane.
Graded potentials
spread over the plasma membrane in decremental fashion.
are not propagated for long distances.
are confined to a small region of the plasma membrane.
can summate.
All of these are correct.
All of these are correct.
During the depolarization phase of an action potential, the permeability of the membrane
to K+ is greatly increased.
to Na+ is greatly increased.
to Ca2+ is greatly increased.
is unchanged.
to Na+ is greatly increased.
During repolarization of the plasma membrane,
Na+ diffuses into the cell.
Na+ diffuses out of the cell.
K+ diffuses into the cell.
K+ diffuses out of the cell.
K+ diffuses out of the cell.
The absolute refractory period
limits how many action potentials can be produced during a given period of time.
page 403 prevents an action potential from starting another action potential at the same point on the plasma membrane.
is the period of time when a strong stimulus can initiate a second action potential.
Both a and b are correct.
All of these are correct.
Both a and b are correct.
A subthreshold stimulus
produces an afterpotential.
produces a graded potential.
causes an all-or-none response.
produces more action potentials than a submaximal stimulus.
produces a graded potential.
Neurotransmitter substances are stored in vesicles located in specialized portions of the
neuron cell body.
axon.
dendrite.
postsynaptic membrane.
axon.
In a chemical synapse,
action potentials in the presynaptic terminal cause voltage-gated Ca2+ channels to open.
neurotransmitters can cause ligand-gated Na+ channels to open.
neurotransmitters can be broken down by enzymes.
neurotransmitters can be taken up by the presynaptic terminal.
All of these are correct.
All of these are correct.
An inhibitory presynaptic neuron can affect a postsynaptic neuron by
producing an IPSP in the postsynaptic neuron.
hyperpolarizing the plasma membrane of the postsynaptic neuron.
causing K+ to diffuse out of the postsynaptic neuron.
causing Cl− to diffuse into the postsynaptic neuron.
All of these are correct.
All of these are correct.
Summation
is caused by combining two or more graded potentials.
occurs at the trigger zone of the postsynaptic neuron.
results in an action potential if it reaches the threshold potential.
can occur when two action potentials arrive in close succession at a single presynaptic terminal.
All of these are correct.
All of these are correct.
