Ch. 11 EXAM 4
24) Receives stimuli. A) Receptive region B) Trigger zone C) Conducting region
A
94) Neuroglia found in the CNS that bind axons and blood vessels to each other are called ________.
Astrocytes
15) The interior of the cell becomes less negative due to an influx of sodium ions. A) Action potential B) Absolute refractory period C) Depolarization D) Repolarization E) Relative refractory period
C
Match the following: 111) Principal inhibitory neurotransmitter of the spinal cord.
Glycine
Match the following: 96) "Feel-good" neurotransmitter.
Norepinephrine
Match the following: 105) Mediates pain.
Substance P
TRUE/FALSE 35) Reflexes are rapid, automatic responses to stimuli.
True
TRUE/FALSE 36) Efferent nerve fibers may be described as motor nerve fibers.
True
TRUE/FALSE 37) Cell bodies of sensory neurons may be located in ganglia lying outside the central nervous system.
True
TRUE/FALSE 38) Myelination of the nerve fibers in the central nervous system is the job of the oligodendrocyte.
True
TRUE/FALSE 40) Neurons in the CNS are organized into functional groups.
True
14) Ependymal cells ________. A) help to circulate the cerebrospinal fluid B) are a type of neuron C) are the most numerous of the neuroglia D) are a type of macrophage
A
15) The sheath of Schwann is also called the ________. A) neurilemma B) axolemma C) white matter D) myelin sheath
A
17) Also called a nerve impulse transmitted by axons. A) Action potential B) Absolute refractory period C) Depolarization D) Repolarization E) Relative refractory period
A
17) The substance released at axon terminals to propagate a nervous impulse is called a(n) ________. A) neurotransmitter B) biogenic amine C) ion D) cholinesterase
A
20) Stimulation of a postsynaptic neuron by many terminals at the same time. A) Spatial summation B) Threshold stimulus C) Temporal summation D) Subthreshold stimulus
A
28) Plasma membrane exhibits chemically gated ion channels. A) Receptive region B) Secretory region C) Secretory zone
A
31) Involved in control of rhythmic activities such as breathing. A) Reverberating circuit B) Parallel after-discharge circuit C) Converging circuit D) Diverging circuit
A
60) Bipolar neurons are commonly ________. A) found in the retina of the eye B) found in ganglia C) motor neurons D) called neuroglial cells
A
62) Which of the following describes the nervous system integrative function? A) analyzes sensory information, stores information, makes decisions B) responds to stimuli by gland secretion or muscle contraction C) senses changes in the environment
A
64) Which of the following is not characteristic of neurons? A) They are mitotic. B) They have extreme longevity. C) They have an exceptionally high metabolic rate. D) They conduct impulses.
A
67) An impulse from one nerve cell is communicated to another nerve cell via the ________. A)synapse B) cell body C) receptor D) effector
A
71) The term central nervous system refers to the ________. A) brain and spinal cord B) brain, spinal cord, and peripheral nerves C) spinal cord and spinal nerves D) peripheral and spinal nerves
A
75) Which of the following is not a chemical class of neurotransmitters? A) nucleic acid B) biogenic amine C) acetycholine D) ATP and other purines E) amino acid
A
76) Which of the following is false or incorrect? A) A nerve impulse occurs if the excitatory and inhibitory effects are equal. B) An inhibitory postsynaptic potential occurs if the inhibitory effect is greater than the excitatory, causing hyperpolarization of the membrane. C) An excitatory postsynaptic potential occurs if the excitatory effect is greater than the inhibitory effect but less than threshold.
A
90) If a motor neuron in the body were stimulated by an electrode placed about midpoint along the length of the axon ________. A) the impulse would spread bidirectionally B) muscle contraction would occur C) the impulse would move to the axon terminal only D) the impulse would move to the axon terminal only, and the muscle contraction would occur
A
In a reflex arc, which neuron has its cell body inside the spinal cord?
A
Which is by far the most common neuron type?
A
Which neuron would connect to a muscle?
A
14) The neuron cannot respond to a second stimulus, no matter how strong. A) Action potential B) Absolute refractory period C) Depolarization D) Repolarization E) Relative refractory period
B
22) Any stimulus below this intensity will result in no response in a neuron. A) Spatial summation B) Threshold stimulus C) Temporal summation D) Subthreshold stimulus
B
23) Area where nerve impulse is generated. A) Receptive region B) Trigger zone C) Conducting region
B
26) Plasma membrane exhibits voltage-gated Ca2+ channels. A) Receptive region B) Secretory region C) Secretory zone
B
30) May be involved in complex, exacting types of mental processing. A) Reverberating circuit B) Parallel after-discharge circuit C) Converging circuit D) Diverging circuit
B
59) What does the central nervous system use to determine the strength of a stimulus? A) origin of the stimulus B) frequency of action potentials C) size of action potentials D) type of stimulus receptor
B
61) Which of the following is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle? A) gamma aminobutyric acid B) acetylcholine C) cholinesterase D) norepinephrine
B
63) The period after an initial stimulus when a neuron is not sensitive to another stimulus is the ________. A) resting period B) absolute refractory period C) repolarization D) depolarization
B
80) Schwann cells are functionally similar to ________. A) astrocytes B) oligodendrocytes C) microglia D) ependymal cells
B
83) An inhibitory postsynaptic potential (IPSP) is associated with ________. A) lowering the threshold for an action potential to occur B) hyperpolarization C) a change in sodium ion permeability D) opening of voltage-regulated channels
B
85) When a sensory neuron is excited by some form of energy, the resulting graded potential is called a(n) ________. A) action potential B) generator potential C) postsynaptic potential D) excitatory potential
B
89) In what way does the interior surface of a cell membrane of a resting (nonconducting) neuron differ from the external environment? The interior is ________. A) negatively charged and contains more sodium B) negatively charged and contains less sodium C) positively charged and contains more sodium D) positively charged and contains less sodium
B
91) Which of the following neurotransmitters inhibits pain and is mimicked by morphine, heroin, and methadone? A) nitric oxide B) endorphin C) acetylcholine D) serotonin
B
Which neuron is never myelinated?
B
Which neuron is rare?
B
Which neuron would be found in the retina of the eye?
B
16) Neurons may be classified according to several characteristics. Which of the following is correct? A) Group A fibers are mostly somatic sensory and motor and are the smallest in diameter. B) A small cross-sectional area allows shorter conduction times. C) Group C fibers are not capable of saltatory conduction. D) Group B fibers are highly myelinated and have the highest conduction velocities.
C
19) Numerous nerve impulses arriving at a synapse at closely timed intervals exert a cumulative effect. A) Spatial summation B) Threshold stimulus C) Temporal summation D) Subthreshold stimulus
C
25) Plasma membrane exhibits voltage-gated Na+ and K+ channels. A) Receptive region B) Trigger zone C) Conducting region
C
27) Axon terminals release neurotransmitters. A) Receptive region B) Secretory region C) Secretory zone
C
33) Different types of sensory input can have the same ultimate effect. A) Reverberating circuit B) Parallel after-discharge circuit C) Converging circuit D) Diverging circuit
C
58) What are ciliated CNS neuroglia that play an active role in moving the cerebrospinal fluid called? A) Schwann cells B) oligodendrocytes C) ependymal cells D) astrocytes
C
66) Which ion channel opens in response to a change in membrane potential and participates in the generation and conduction of action potentials? A) leakage channel B) mechanically gated channel C) voltage-gated channel D) ligand-gated channel
C
69) Which of the following is not a function of the autonomic nervous system? A) innervation of smooth muscle of the digestive tract B) innervation of glands C) innervation of skeletal muscle D) innervation of cardiac muscle
C
72) The substance released at axon terminals to propagate a nervous impulse is called a(n) ________. A) cholinesterase B) ion C) neurotransmitter D) biogenic amine
C
73) A neuron that has as its primary function the job of connecting other neurons is called a(n) ________. A) afferent neuron B) glial cell C) association neuron D) efferent neuron
C
74) Saltatory conduction is made possible by ________. A) large nerve fibers B) erratic transmission of nerve impulses C) the myelin sheath D) diphasic impulses
C
77) Select the correct statement regarding synapses. A) Cells with gap junctions use chemical synapses. B) The release of neurotransmitter molecules gives cells the property of being electrically coupled. C) The synaptic cleft prevents an impulse from being transmitted directly from one neuron to another. D) Neurotransmitter receptors are located on the axons terminals of cells.
C
79) Neuroglia that control the chemical environment around neurons by buffering potassium and recapturing neurotransmitters are ________. A) microglia B) oligodendrocytes C) astrocytes D) Schwann cells
C
87) Which of the following is true about the movement of ions across excitable living membranes? A) Ions always move from an area of higher concentration to an area of lower concentration B) Ions always move actively across membranes through leakage channels. C) Sodium gates in the membrane can open in response to electrical potential changes. D) Ions always move passively across membranes.
C
Which neuron is a sensory neuron found in a reflex arc?
C
Which neuron is common only in dorsal root ganglia of the spinal cord and sensory ganglia of cranial nerves?
C
16) The specific period during which potassium ions diffuse out of the neuron due to a change in membrane permeability. A) Action potential B) Absolute refractory period C) Depolarization D) Repolarization E) Relative refractory period
D
21) An insufficient stimulus. A) Spatial summation B) Threshold stimulus C) Temporal summation D) Subthreshold stimulus
D
29) One incoming fiber triggers responses in ever-increasing numbers farther and farther along the circuit. A) Reverberating circuit B) Parallel after-discharge circuit C) Converging circuit D) Diverging circuit
D
3) Select the correct statement about serial processing. A) Memories are triggered by serial processing. B) Input travels along several different pathways. C) Smells are processed by serial pathways. D) Spinal reflexes are an example of serial processing.
D
32) Involved in activating fibers of a skeletal muscle such as the biceps muscle. A) Reverberating circuit B) Parallel after-discharge circuit C) Converging circuit D) Diverging circuit
D
5) Which of the following is true about the movement of ions across excitable living membranes? A) The bulk of the solutions inside a cell are negatively charged. B) Sodium gates in the membrane can open in response to electrical potential changes. C) Ions always move actively across membranes through leakage channels. D) Some ions are prevented from moving down their concentration gradients by ATP-driven pumps.
D
57) Which of the choices below describes the ANS? A) motor fibers that conduct nerve impulses from the CNS to skeletal muscles B) sensory and motor neurons that supply the digestive tract C) sensory neurons that convey information from somatic receptors in the head, body wall, and limbs and from receptors from the special senses of vision, hearing, taste, and smell to the CNS D) motor fibers that conduct nerve impulses from the CNS to smooth muscle, cardiac muscle, and glands
D
65) The part of a neuron that conducts impulses away from its cell body is called a(n) ________. A) dendrite B) neurolemma C) Schwann cell D) axon
D
68) What is the role of acetylcholinesterase? A) act as a transmitting agent B) amplify or enhance the effect of ACh C) stimulate the production of acetylcholine D) destroy ACh a brief period after its release by the axon endings
D
70) Collections of nerve cell bodies outside the central nervous system are called ________. A) tracts B) nuclei C) nerves D) ganglia
D
78) Which of the following correctly describes a graded potential? A) long distance signaling B) voltage stimulus to initiate C) voltage regulated repolarization D) amplitude of various sizes
D
81) Immediately after an action potential has peaked, which cellular gates open? A) calcium B) chloride C) sodium D) potassium
D
82) Nerve cell adhesion molecules (N-CAMs) ________. A) release nerve growth factor B) are crucial in the production of neurotransmitters C) are found on "pathfinder" neurons D) are crucial for the development of neural connections
D
84) Which of the following will occur when an excitatory postsynaptic potential (EPSP) is being generated on the dendritic membrane? A) Specific potassium gates will open. B) Sodium gates will open first, then close as potassium gates open. C) Specific sodium gates will open. D) A single type of channel will open, permitting simultaneous flow of sodium and potassium.
D
86) Which of the following is not true of graded potentials? A) They are short-lived. B) They can form on receptor endings. C) They can be called postsynaptic potentials. D) They increase amplitude as they move away from the stimulus point.
D
88) A second nerve impulse cannot be generated until ________. A) the Na ions have been pumped back into the cell B) all sodium gates are closed C) proteins have been resynthesized D) the membrane potential has been reestablished
D
92) Which of the following describes the excitatory postsynaptic potential? A) short distance hyperpolarization B) moves membrane potential away from threshold C) opens K+ or Cl- channels D) short distance depolarization
D
18) An exceptionally strong stimulus can trigger a response. A) Action potential B) Absolute refractory period C) Depolarization D) Repolarization E) Relative refractory period
E
56) Which of the following is not a function of astrocytes? A) anchor neurons to blood vessels B) support and brace neurons C) control the chemical environment around neurons D) guide the migration of young neurons, synapse formation, and helping to determine capillary permeability E) provide the defense for the CNS
E
97) The synapse more common in embryonic nervous tissue than in adults is the ________.
Electrical synapse
Match the following: 109) Natural opiates that inhibit pain; effect mimicked by morphine.
Endorphins
TRUE/FALSE 34) The all-or-none phenomenon as applied to nerve conduction states that the whole nerve cell must be stimulated for conduction to take place.
False
TRUE/FALSE 41) Strong stimuli cause the amplitude of action potentials generated to increase.
False
TRUE/FALSE 47) The nodes of Ranvier are found only on myelinated, peripheral neuron processes.
False
TRUE/FALSE 52) The autonomic nervous system is under voluntary control; whereas, the somatic nervous system is involuntary.
False
99) Potentials that are short-lived, local changes in membrane potential that can be either depolarized or hyperpolarized are called ________ potentials.
Graded
Match the following: 94) Increases acid secretion in the stomach; blocked by cimetidine.
Histamine
95) A chemical messenger that does not directly cause ESPSs or IPSPs but does affect the strength of synaptic transmission is a ________.
Neuromodulator
98) When information is delivered within the CNS simultaneously by different parts of the neural pathway, the process is called ________ processing.
Parallel
93) That part of the nervous system that is voluntary and conducts impulses from the CNS to the skeletal muscles is the ________ nervous system.
Somatic
100) When one or more presynaptic neurons fire in rapid order it produces a much greater depolarization of the postsynaptic membrane than would result from a single EPSP; this event is called ________ summation.
Temporal
TRUE/FALSE 39) During depolarization, the inside of the neuron's membrane becomes less negative.
True
TRUE/FALSE 42) The oligodendrocytes can myelinate several axons.
True
TRUE/FALSE 43) Enkephalins and endorphins are peptides that act like morphine.
True
TRUE/FALSE 44) In myelinated axons the voltage-regulated sodium channels are concentrated at the nodes of Ranvier.
True
TRUE/FALSE 45) A postsynaptic potential is a graded potential that is the result of a neurotransmitter released into the synapse between two neurons.
True
TRUE/FALSE 46) Large-diameter nerve fibers conduct impulses much faster than small-diameter fibers.
True
TRUE/FALSE 48) Unipolar neurons have axons structurally divided into peripheral and central processes.
True
TRUE/FALSE 49) A stimulus traveling toward a synapse appears to open calcium ion channels at the presynaptic end, which in turn promotes fusion of synaptic vesicles to the axonal membrane.
True
TRUE/FALSE 50) If bacteria invaded the CNS tissue, microglia would migrate to the area to engulf and destroy them.
True
TRUE/FALSE 51) The overlapping functions of the nervous system are sensory input, integration, and motor output.
True
TRUE/FALSE 53) Axon diameter and degree of myelination determine nerve impulse conduction velocity.
True
TRUE/FALSE 54) The action potential is caused by permeability changes in the plasma membrane.
True
TRUE/FALSE 55) Some neurotransmitters can be either excitatory or inhibitory depending upon the receptor.
True
