A and P 1 Chapter 11
Which of the following diseases is directly related to demyelination? A. muscular dystrophy B. cerebral palsy C. multiple sclerosis D. lupus
multiple sclerosis
Which of the following divisions of the nervous system is also known as the involuntary nervous system? A. the somatic nervous system B. the autonomic nervous system C. the spinal division of the nervous system D. the peripheral nervous system
the autonomic nervous system
From where can collaterals emerge on a myelinated nerve?
the nodes of Ranvier
"carrying away"
Efferent
Cells that line the cerebrospinal fluid filled cavities
Ependymal
Which of the following events occurs at an electrical synapse? A. Calcium channels open in the presynaptic region. B. Neurotransmitters bind to the postsynaptic receptors. C. A neurotransmitter is released by exocytosis. D. Ions flow directly from one neuron to the next. E. Neurotransmitters diffuse across the synaptic cleft.
Ions flow directly from one neuron to the next.
Defensive cells of CNS
Microglial
Which of the following is FALSE regarding motor (efferent) neurons? A. Motor (efferent) neurons are bipolar. B. Motor (efferent) neurons carry impulses away from the CNS to the effector organs. C. Impulses from motor (efferent) neurons cause activity in skeletal muscles and glands. D. The cell bodies of most motor (efferent) neurons are located in the CNS.
Motor (efferent) neurons are bipolar.
Which of the following is NOT a characteristic of neurons? A. In general, neurons cannot be replaced if destroyed. B. Neurons require continuous and abundant supplies of oxygen, and cannot survive for more than a few minutes without it. C. Neurons can function optimally for over 100 years. D. Neurons are relatively small, simple-structured cells.
Neurons are relatively small, simple-structured cells.
What is the difference between the clusters of cell bodies called nuclei and those known as ganglia?
Nuclei exist in the CNS, ganglia in the PNS.
Cells that have processes that form myelin sheaths arounf CNS nerve fibers
Oligodendrocytes
An exceptionally strong stimulus can trigger a response.
Relative refractory period
These 2 cell types form myelin and surround neurons in the PNS
Satellite and Schwann
Which of the following best describes the nervous system function of integration? A. The nervous system causes a response by activating effector organs, such as the muscles and glands. B. The nervous system uses its millions of sensory receptors to monitor changes occurring both inside and outside the body. C. The nervous system generates neurons in order to replace or repair damaged neurons; this permits optimal communication between the CNS and the body's effector organs. D. The nervous system processes and interprets sensory input and decides what should be done at each moment.
The nervous system processes and interprets sensory input and decides what should be done at each moment.
Which of the following explains the inability of a neuron to respond to a second stimulus of equal strength to the first stimulus to which it has already responded? A. Action potential generation is an all-or-none phenomenon. B. The neuron is myelinated. C. The neuron is in the absolute refractory period. D. Neurons are amitotic.
The neuron is in the absolute refractory period.
Which of the following statements concerning inhibitory synapses (IPSPs) is correct? A. Channels allow both sodium and potassium ions to diffuse simultaneously through the membrane. B.The permeability of the postsynaptic membrane to sodium, potassium, and chloride is not changed. C. The postsynaptic membrane becomes less permeable to potassium. D. The postsynaptic membrane becomes less permeable to sodium. E. The postsynaptic membrane becomes more permeable to potassium and chloride.
The postsynaptic membrane becomes more permeable to potassium and chloride.
What is the primary difference between the somatic nervous system and the autonomic nervous system?
The somatic nervous system allows us to consciously control our skeletal muscles, and the autonomic nervous system controls activity that humans cannot consciously control, such as the pumping of the heart and the movement of food through the digestive tract.
Which type of ion channel opens when a chemical binds to it? A. leakage channel B. voltage-gated channel C. mechanically gated channel D. chemically gated (ligand-gated) channel
chemically gated (ligand-gated) channel
In a __________ circuit, multiple presynaptic neurons innervate a single postsynaptic neuron.
converging
The interior of the cell becomes less negative due to an influx of sodium ions.
depolarization
Which of the following circuit types is exemplified by impulses that travel from a single neuron of the brain, activate one hundred or more motor neurons in the spinal cord, and excite thousands of skeletal muscle fibers? A. parallel after-discharge circuit B. reverberating circuit C. converging circuit D. diverging circuit
diverging circuit
Which of the following neurotransmitters act(s) as a natural opiate? A. endorphins B. epinephrine C. GABA D. dopamine E. serotonin
endorphins
Which cells line the central cavities of the brain and spinal cord and provide a fairly permeable barrier between the CSF and nervous tissue?
ependymal cells
Which of the following types of glial cells line the central cavities of the brain and spinal cord, where they help to circulate the cerebrospinal fluid? A. microglial cells B. astrocytes C. ependymal cells D. oligodendrocytes
ependymal cells
Collections of nerve cell bodies in the peripheral nervous system are called _______________________.
ganglia
collections of neuron cell bodies
ganglia
In a neuron, a membrane potential of -90 mV is considered __________.
hyperpolarized
The CNS can discriminate between strong and weak stimuli as strong stimuli __________.
increase the frequency of action potentials
Which of the following factors is associated with increased conduction velocity in an axon? A. increased number of dendrites B. small diameter C. large diameter D. presence of collaterals E. the absence of the myelin sheath
large diameter
Which of the following membrane ion channels in the neuron are always open? A. ligand-gated channels B. voltage-gated channels C. mechanically gated channels D. leakage channels
leakage channels
During depolarization, the inside of the neuron's membrane becomes ______________.
less negative
Enkephalins and endorphins are peptides that act like ___________.
morphine
Spatial summation occurs when __________.
multiple local potentials occur at different places on the same cell at the same time
Neurons can be classified structurally by the number of processes extending from their cell bodies. Which of the following is the most common neuron type in humans?
multipolar
mostly consists of pairs of cranial nerves, spinal nerves, and associated ganglia.
peripheral nervous system
The movement of which ion out of the cell through leakage channels establishes the negative membrane potential? A. chloride B. calcium C. sodium D. potassium
potassium
Relative to extracellular fluid, the interior of a neuron has a negative charge because __________.
potassium diffuses out of the cell
Define integration.
processing and interpreting sensory input and determining what should be done at each moment in the body
The sodium-potassium ion pump will __________. A. pump one potassium ion out of the cell for every ion of sodium it brings into the cell B. pump three potassium ions out of the cell for every two sodium ions it brings into the cell C. pump three sodium ions out of the cell for every two ions of potassium it brings into the cell D. pump one sodium ion out of the cell for every ion of potassium it brings into the cell
pump three sodium ions out of the cell for every two ions of potassium it brings into the cell
During which phase of an action potential are voltage-gated K+ channels open, while voltage-gated Na+ channels are closed?
repolarization
The specific period during which potassium ions diffuse out of the neuron due to a change in membrane permeability.
repolarization
Which part of the action potential occurs when the voltage-gated Na+ channels are inactivating and voltage-gated K+ channels open?
repolarization
Organelles slated for degradation or recycling are moved through the axon by ___________.
retrograde movement
The Nissl bodies in the neuron cell body are otherwise known as which cellular organelle(s)?
rough endoplasmic reticulum
Which of the following is NOT a structural classification of neurons? A. multipolar B. sensory C. bipolar D. unipolar
sensory
The sensory, or afferent, division of the peripheral nervous system transmits information from the __________ to the CNS.
skin
Which of the following characteristics is NOT associated with a myelinated nerve fiber? A. slow conduction of nerve impulses B. the presence of nodes of Ranvier C. formation by oligodendrocytes in the central nervous system D. rapid conduction of nerve impulses E. formation by Schwann cells in the peripheral nervous system
slow conduction of nerve impulses
In myelinated axons the voltage-regulated sodium channels are concentrated at _______________.
the nodes of Ranvier
Which criterion is used to structurally classify neurons?
the number of processes extending from their cell body
Which of the following is NOT a function of the myelin sheath? A. to recapture and recycle released neurotransmitters B. to protect nerve fibers C. to electrically insulate nerve fibers D. to increase the speed of transmission of nerve impulses
to recapture and recycle released neurotransmitters
Which of the following membrane ion channels open and close in response to changes in the membrane potential? A. voltage-gated channels B .mechanically gated channels C .chemically gated channels D. nongated channels
voltage-gated channels
Which of the following is characteristic of an action potential? A. travels a short distance B. occurs in the dendrites and cell body C. absent of positive feedback D. voltage-gated ion channels
voltage-gated ion channels
The most abundant CSN neuroglia.
Astrocytes
include astrocytes, microglial cells, ependymal cells, and oligodendrocytes
Neuroglia in the CNS
consists of a spherical nucleus with a conspicuous nucleolus surrounded by cytoplasm
Neuron cell body
carry impulses to and from the spinal cord
Spinal nerves
Which of the following are the main receptive or input regions found in neurons? A. dendrites B. ganglia C. neurofibrils D. axons
dendrites
Which of the following conditions would cause synaptic potentiation? A. influx of Ca++ B. influx of Na+ C. influx of Cl- D. K+ efflux
influx of Ca++
An action potential is a phenomenon that either happens completely or doesn't happen at all. True OR False
True
Dendrites and axons are both armlike processes that extend from neuron cell bodies. True OR False
True
The neuron cannot respond to a second stimulus, no matter how strong.
absolute refractory period
Which of the following is NOT a biogenic amine neurotransmitter? A. norepinephrine B. dopamine C. serotonin D. acetylcholine E. epinephrine
acetylcholine
_____________ is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle.
acetylcholine
Which of the following substances is NOT a neurotransmitter? A. epinephrine B. acetylcholinesterase C. histamine D. carbon dioxide
acetylcholinesterase
Which of the following electrical events occurs when a certain threshold is reached? A. EPSP B. IPSP C. action potential D. resting membrane potential
action potential
Which of the following neuroglia are most responsible for helping determine capillary permeability in the central nervous tissue? A. oligodendrocytes B. microglial cells C. Schwann cells D. ependymal cells E. astrocytes
astrocytes
Which of the following types of glial cells are the most abundant and versatile, and aid in making exchanges between capillaries and neurons? A. astrocytes B. ependymal cells C. oligodendrocytes D. microglial cells
astrocytes
Which of the following is a rare type of sensory neuron that is found in special sensory structures such as the retina of the eye? A. multipolar B. pseudounipolar C. unipolar D. bipolar
bipolar
The term central nervous system refers to the ___________________.
brain and spinal cord
The brain and spinal cord make up the
central nervous system.
Which of the following is NOT a functional classification of neurotransmitters? A. excitatory B. direct C. chemical D. indirect
chemical
Also called a nerve impulse transmitted by axons.
Action potential
Carrying to or toward a center.
Afferent
Which of the following statements best describes the resting membrane state in the neuron? A. Only the voltage-gated K+ are closed. B. Only the voltage-gated Na+ channels are closed. C. Only the voltage-gated Na+ channels are open. D. Only the voltage-gated K+ channels are open. E. All of the voltage-gated Na+ and K+ channels are closed.
All of the voltage-gated Na+ and K+ channels are closed.
Nerve fibers
Axon
What is the difference between nerves and tracts?
Bundles of neuron processes are called tracts in the CNS and nerves in the PNS.
is the integrating and control center of the nervous system. It interprets sensory input and dictates motor output based on reflexes, current conditions, and past experience.
CSN
Which of the following is FALSE regarding chemical synapses? A. They communicate unidirectionally. B. They transmit nerve impulses directly from one neuron to another. C. They possess pre- and postsynaptic membranes separated by a synaptic cleft. D. Each is composed of an axon terminal and a receptor region.
They transmit nerve impulses directly from one neuron to another.