HCS 212 TEST BANK 13
As an axon regenerates in the PNS, ________ wrap around it along its original path.
Schwann cells or neurolemmocytes
A neuron might be temporarily unable to transmit an impulse to another if A) its supply of neurotransmitters is exhausted. B) the neurons are of different types. C) the levels of microglia are too low. D) there are too many astrocytes present. E) you are asleep.
a
At a vesicular synapse the neurons communicate by A) neurotransmitters. B) communicating junctions. C) terminal arborizations. D) nodes. E) internodes.
a
Axons extending from a peripheral ganglion to an effector are called A) postganglionic fibers. B) ganglionic fibers. C) preganglionic fibers. D) efferent fibers. E) afferent fibers.
a
The neural tissue of the body contains approximately ________ glial cells.
100 billion
The most common neurotransmitter is ________.
acetylcholine
Because a neuron loses its centrioles, A) it is rendered incapable of dividing. B) it cannot grow as quickly as neurons that retain their centrioles. C) it loses its normal ability to produce a myelin sheath. D) it is probably located in the PNS. E) All of the answers are correct.
a
To transmit a nerve impulse, acetylcholine diffuses across a space called the ________ to bind to receptors on the postsynaptic membrane.
synaptic cleft
A group of neuron cell bodies in the CNS that has a descrete boundary is called a A) soma. B) ganglion. C) nucleus. D) column. E) center.
c
A neuron pool is A) a group of identical nerve cells. B) a group of neurons linked by communicating junctions. C) a group of interconnected neurons with specific functions. D) the group of neurons available to regenerate a damaged nerve. E) a group of neurons linked by electrical synapses.
c
Demyelination A) is the addition of myelin to the axon. B) is the thickening of the myelin sheath. C) is the gradual reduction in myelin. D) only affects Schwann cells. E) only affects oligodendrocytes.
c
Muscles, glands, and special cells that respond to neural stimuli are called A) receptors. B) reflexes. C) effectors. D) axons. E) dendrites.
c
Organized masses of axons and neuron cell bodies in both the CNS and the PNS A) are usually demyelinated. B) are called neuroglia. C) have distinct anatomical boundaries. D) compose the neural cortex. E) None of the answers are correct.
c
The portion of a neuron that carries information in the form of a nerve impulse is called the A) soma. B) Nissl body. C) axon. D) dendrite. E) myelin.
c
A communicating junction acts to facilitate A) the passage of neurotransmitters between cells. B) growth of Schwann cells. C) a change in the permeability of the postsynaptic membrane. D) the passage of ions between the cells. E) All of the answers are correct.
d
Areas of the nervous system that are dense in myelinated axons are referred to as A) arachnoid mater. B) gray matter. C) dura mater. D) white matter. E) pia matter.
d
Cells responsible for information processing and transfer are A) astrocytes. B) neuroglia. C) Schwann cells. D) neurons. E) All of the answers are correct.
d
Generation of an action potential at an axon of a neuron may be caused by A) stimulation of any portion of the dendrites of the neuron. B) input from various presynaptic cells. C) a change in the number of Schwann cells surrounding the axon. D) stimulation of any portion of the dendrites of the neuron and/or input from various presynaptic cells. E) All of the answers are correct.
d
If the CNS was susceptible to a drug that should not affect it, this might indicate damage to which of the following cells? A) microglia B) Schwann cells C) satellite cells D) astrocytes E) ependymal cells
d
Involuntary cardiac muscle fibers on the heart are innervated by A) sensoriganglionic fibers. B) preganglionic fibers. C) somatic motor fibers. D) visceral motor fibers. E) All of the answers are correct.
d
Nonvesicular synapses are unique because they have A) two interacting neurons. B) neurotransmitter release. C) a postsynaptic membrane. D) a communicating junction. E) receptor proteins.
d
Over 50 different neurotransmitters have been identified, but the best known is A) norepinephrine. B) epinephrine. C) glutamate. D) acetylcholine. E) GABA.
d
Pathways that connect the CNS with effectors are A) motor pathways. B) descending pathways. C) efferent pathways. D) All of the answers are correct. E) None of the answers are correct.
d
Satellite cells surround the cell bodies of peripheral neurons, which can be found in (the) A) nuclei. B) peripheral centers. C) roots. D) ganglia. E) All of the answers are correct.
d
The central nervous system (CNS) includes the A) brain. B) spinal cord. C) nerves. D) brain and spinal cord. E) nerves and muscles.
d
To contact a Schwann cell, where would a microprobe have to be inserted in the nervous system? A) anywhere in the CNS B) near or at a neuron cell body C) alongside an unmyelinated axon in the CNS D) along any axon in the PNS, myelinated or not E) None of the answers are correct.
d
Which of the following selections lists only types of glial cells? A) astrocytes and parenchymal cells B) apocrine and exocrine cells C) merocrine, platelet, and ependymal cells D) microglia, oligodendrocytes, and Schwann cells E) None of the answers are correct.
d
Which of the following structures do not contribute to the coarse grainy appearance of the perikaryon of a neuron? A) mitochondria B) free and fixed ribosomes C) rough endoplasmic reticulum D) smooth endoplasmic reticulum E) All of the answers are correct.
d
Which type of cell can only be found in the central nervous system? A) neurons B) satellite cells C) Schwann cells D) oligodendrocytes E) None of the answers are correct.
d
The processes of a neuron that function to receive input from other neurons are called the ________.
dendrites
Cardiac muscle, smooth muscle, and glands are under the control of the A) somatic nervous system. B) parasympathetic division. C) sympathetic division. D) central nervous system. E) autonomic nervous system.
e
Functions of the nervous system include which of the following? A) controlling and adjusting the activities of the other systems B) receiving input from the senses C) stimulating muscles and glands to contract D) integrating and processing data E) All of the answers are correct.
e
The characteristic of the neuron plasmalemma that allows it to conduct impulses is called ________.
excitability
Glial cells outnumber neurons in the nervous system by a ratio of approximately ________ to one. (Note: Be sure to spell out your answer).
five
In the PNS the neuron cell bodies are found in clusters called ________.
ganglia
Neurons that form a link between other neurons in the CNS are called ________.
interneurons
The nervous system includes all of the ________ tissue in the body.
neural
Bundles of neurofilaments, called ________, which form part of the cytoskeleton of the perikaryon, extend into the dendrites and the axon.
neurofibrils
The type of synapse that allows the most direct communication between cells, and therefore the fastest communication, is the ________ synapse.
nonvesicular
A type of information processing wherein neuronal pools function in sequence, with one pool activating a second, the second activating a third, etc., is called ________.
serial processing
A neuromuscular synapse is a type of ________ synapse in which a neuron communicates with a muscle fiber instead of another neuron.
vesicular
Interneurons within the ________ are organized into a smaller number of neuronal pools.
CNS
Degeneration of an axon distal to the site of an injury is called ________.
Wallerian degeneration
If all of the glial cells of the nervous system were destroyed, which of the following would occur? A) Less than 20 percent of the cells of the nervous system would remain. B) Only the PNS would be adversely affected. C) The mass of the nervous system would be reduced by about 25 percent. D) The rate of neuronal replacement would decline significantly. E) The choroid plexus could not generate CSF.
a
If the point of an extremely small probe were passed into a satellite cell, it would be located in which region of the nervous system? A) near a cell body in a ganglion of the PNS B) near the axon of a neuron in the CNS C) near the lining of the ventricles of the brain D) at a neuromuscular synapse E) None of the answers are correct.
a
Injured neurons can recover their functional capabilities if A) the oxygen and nutrient supplies are restored. B) the cause of the damage is removed within a period of weeks. C) the cells can divide enough times to replace those that are lost. D) All of the answers are correct. E) None of the answers are correct.
a
The anatomical subdivisions of the nervous system are (the) A) central and peripheral nervous systems. B) dorsal and ventral nervous systems. C) appendicular and axial nervous systems. D) autonomic and somatic nervous systems. E) None of the answers are correct.
a
The effects of a neurotransmitter on the postsynaptic membrane include which of the following? A) Excitatory or inhibitory responses. B) Neurotransmitter molecules are absorbed by the postsynaptic cell. C) The neurotransmitter floats around in the synaptic cleft. D) Upon stimulation, the membrane releases more neurotransmitter molecules. E) None of the answers are correct.
a
The functional classifications of neurons includes ________, which carry information toward the CNS. A) sensory neurons B) interneurons C) motor neurons D) axoplasmic neurons E) All of the answers are correct.
a
Which of the following is gray matter? A) neural cortex B) columns C) tracts D) ganglia E) nerves
a
A nerve impulse triggers events at a synapse or junction that A) usually connect the cell bodies of two neurons directly. B) transfer information either to another neuron or to an effector cell. C) continue to respond only if it is myelinated. D) are always inhibitory unless followed by similar impulses. E) None of the answers are correct.
b
Action potentials result from A) closing of ion channels. B) abrupt changing of the transmembrane potential. C) opening of calcium gates. D) neurons transporting neurotransmitters. E) All of the answers are correct.
b
An inhibitory response A) makes an action potential more likely. B) makes an action potential less likely. C) directly causes an action potential. D) causes ACh release. E) None of the answers are correct.
b
Areas of a myelinated axon that are not covered by myelin are called A) internodes. B) nodes. C) gray matter. D) white matter. E) All of the answers are correct.
b
Areas of gray matter in the interior of the CNS form larger groups called A) spinal nerves. B) nuclei. C) cranial nerves. D) columns. E) reverberating neurons.
b
In the case of most neurons, the arrival of a nerve impulse at the terminal bouton immediately triggers A) a change in the permeability of the postsynaptic plasmalemma. B) release of ACh at the presynaptic membrane. C) generation of an action potential in the axon. D) long-lived effects at the synaptic membrane. E) an action potential.
b
In the process known as Wallerian degeneration, A) the axon proximal to the injury degenerates. B) macrophages remove the debris of damaged axons. C) Schwann cells completely degenerate. D) no trace is left of the path taken by a previous axon. E) All of the answers are correct.
b
Microglia are (the) A) most numerous neuroglial cell. B) smallest neuroglial cell. C) not a neuroglial cell. D) least numerous neuroglial cell. E) None of the answers are correct.
b
Movement of nutrients, wastes, and organelles between the cell body and axon terminals is called A) axonal transport. B) axoplasmic transport. C) osmosis. D) diffusion. E) neurofibular contraction.
b
Myelin is (a) A) cell body. B) mostly lipid. C) special cell that protects neurons. D) special area of the brain. E) None of the answers are correct.
b
Nerve impulse transmission between cells of the CNS without any delay can be attributed to A) the presence of a neuromuscular synapse between the cells. B) communicating junctions that permit the passage of ions between the cells. C) the activity of Schwann cells. D) the number of neurons in the chain. E) drinking an energy drink.
b
Neuroglia in the nervous system function to A) carry nerve impulses. B) support the neurons. C) process information in the nervous system. D) transfer nerve impulses from the brain to the spinal cord. E) All of the answers are correct.
b
Neurotransmitters are A) produced on command. B) stored in synaptic vesicles. C) never recycled. D) released only at nonvesicular synapses. E) produced by astrocytes.
b
Receptors may be classified as A) effectors and muscles. B) somatic and visceral. C) glands and muscles. D) voluntary and involuntary. E) subconscious and conscious.
b
The outermost covering of a myelinated axon is called (the) A) axolemma. B) neurolemma. C) sarcolemma. D) internode. E) None of the answers are correct.
b
The rate of conduction of a nerve impulse depends upon A) properties of the soma of the neuron. B) the presence or absence of a myelin sheath. C) the number of cell dendrites. D) the type of neurotransmitter present. E) All of the answers are correct.
b
The surface of the brain is called the A) higher center. B) neural cortex. C) neuronal nuclei. D) white matter. E) basal nuclei.
b
What is the correct sequence of events at a synapse? (1) neurotransmitter release/diffusion (2) generation of action potential in the postsynaptic cell axon (3) arrival of nerve impulse at synaptic knob in presynaptic cell (4) removal of neurotransmitter molecules from receptors (5) binding of neurotransmitter to receptors A) 2, 3, 1, 5, 4 B) 3, 1, 5, 2, 4 C) 3, 1, 5, 4, 2 D) 2, 3, 1, 4, 5 E) 1, 5, 4, 2, 3
b
When a neural pathway splits to involve many areas of the nervous system, the type of processing is known as A) parallel. B) diverging. C) converging. D) serial. E) reverberating.
b
Which of the following neuroglia produce cerebrospinal fluid? A) astrocytes B) ependymal cells C) microglia D) oligodendrocytes E) satellite cells
b
The process of reverberation involves A) a negative feedback loop through nerve circuits. B) a single repeat of a stimulus prior to extinction. C) extension of collateral axons back toward the source of an impulse and further stimulation of the presynaptic neurons. D) several neuronal pools processing information at one time. E) All of the answers are correct.
c
The structural classification of a neuron is based upon A) the size of the dendrites. B) the number of axons. C) the number of processes that project from the cell body. D) the type of chemical neurotransmitter it secretes. E) the overall size of the cell.
c
A biopsy of infected or injured tissue from the CNS will most likely show an elevated number of A) ependymal cells. B) oligodendrocytes. C) satellite cells. D) microglia. E) interneurons.
d
Cerebrospinal fluid is produced by ________.
ependymal cells
Functions of the peripheral nervous system include A) providing sensory information to the CNS only. B) making higher order decisions to interpret sensory inputs. C) carrying motor commands to the peripheral tissues and systems only. D) carrying information up and down the spinal cord. E) providing sensory information to the CNS and carrying motor commands to the peripheral tissues and systems.
e
Pathways leading from the receptors to the CNS are called A) afferent pathways. B) efferent pathways. C) sensory pathways. D) motor pathways. E) both afferent and sensory pathways.
e
Subdivisions of the peripheral nervous system (PNS) include A) the somatic nervous system. B) the autonomic nervous system. C) the special sensory receptors. D) the visceral sensory receptors. E) All of the answers are correct.
e
The activity of the nervous system is dependent upon A) large amounts of energy. B) cellular connections. C) a proper extracellular environment. D) a proper intracellular environment. E) All of the answers are correct.
e
The area that connects the cell body to the axon is called the A) neurofibril. B) Nissl body. C) axoplasm. D) initial segment. E) axon hillock.
e
Types of synapses include which of the following? A) axoaxonic B) axodendritic C) axosomatic D) neuroeffector synapses E) All of the answers are correct.
e
Which of the following are examples of neuroeffector synapses? A) neuromuscular synapse B) neuroglandular synapse C) neuroneural synapse D) neuroaxonic synapses E) both neuromuscular synapse and neuroglandular synapse
e
Which of the following are most closely involved with somatic sensory neurons? A) visceral sensory neurons B) bipolar neurons C) interoceptors D) proprioceptors E) exteroceptors
e
The ________ division of the PNS sends motor information to muscles and glands.
efferent
The nervous system and the ________ system share important structural and functional characteristics, such as relying upon some form of chemical communication with targeted tissues and organs.
endocrine
A group of cell bodies within the PNS is called a nucleus.
false
A neuron classified on the basis that it delivers information to the CNS is a motor neuron.
false
A neuron with one axon and one dendrite, with the soma between them is a pseudounipolar neuron.
false
A neuron with the dendrite continuous with the axon, and the cell body off to the side is a bipolar neuron.
false
A somatic motor neuron controls smooth and cardiac muscles.
false
Proprioceptors are sensory receptors that monitor the position of skeletal muscles and ________.
joints
The afferent division of the PNS begins at the ________ and ends at the CNS.
receptors
At a neuromuscular synapse, the action potential is generated in the plasmalemma, or ________, of a muscle fiber.
sarcolemma
The cell body of a neuron may contain synapses numbering in the ________.
thousands
Collections of axons in the CNS that have a common origin and destination are called ________.
tracts
A bundle of axons in the PNS is called a nerve.
true
A bundle of axons within the CNS that shares a common origin, destination, and function is called a tract.
true
A connection between the brain and other organs in the body is called a pathway.
true
A group of axons in a specific region of the spinal cord is called a column.
true
A neuron with several dendrites but a single axon, which may have many branches is a multipolar neuron.
true
A small neuron with processes that cannot be distinguished from axon to dendrite is called an anaxonic neuron.
true
A somatic motor neuron controls skeletal muscle.
true
Somatic sensory receptors receive information from the skin about touch, pain, and temperature.
true
Special sensory receptors receive information in the eyes, ears, nose, and mouth.
true
Visceral sensory receptors receive information from internal organs.
true