Physiology Chapters 8,9,10 – Flashcards

Projections that carry sensory information to the brain A. Grey matter B. White Matter C. Ascending tracts D. Descending tracts E. Propriospinal tracts

location of voltage-gated ion channels A. Dendrites B. Axon C. Cell body

Which of the following statements regarding pathways for somatic perception projection is correct? A. The tertiary sensory neurons cross-over the body's midline. B. The synapse for the secondary to tertiary sensory neuron is within the medulla. C. The longest of the secondary sensory neurons transmit fine touch and proprioceptive information. D. Primary sensory neurons from the hands project to a specific region of the somatosensory cortex. E. Primary sensory neurons that respond to cold sensation project to the same region of the somatosensory cortex.

The term axonal transport refers to A. the release of neurotransmitter molecules from the axon. B. the transport of microtubules to the axon for structural support. C. vesicle transport of proteins and organelles down the axon. D. the movement of the axon terminal to synapse with a new postsynaptic cell. E. None of the answers are correct.

Branches that sometimes occur along the length of an axon are called A. dendrites. B. axon terminals. C. collaterals. D. axon hillocks. E. synapses.

Composed of many small nuclei, an area that integrates as well as relays sensory information that passes through it A. Cerebellum B. Hypothalamus C. Thalamus D. Cerebrum

Contains corticospinal tracts, the pyramids, and control centers for breathing, swallowing, and blood pressure A. Medulla oblongata B. Pons C. Midbrain D. Reticular formation

The total amount of neurotransmitter released at the axon terminal is directly related to A. the amplitude of the action potential. B. the length of the axon. C. the total number of action potentials. D. the amplitude of the graded potential.

The brain's association of activation of a receptor with the perception of a particular sensation is called ________.

The two-point discrimination test A. is used to determine clarity of vision. B. provides information about olfactory receptors. C. provides a measure of receptive field size for touch receptors. D. is used to test for hearing disorders. E. monitors the activity of taste buds.

Which of the following would be an adequate stimulus for a chemoreceptor? A. oxygen B. cell stretch C. photon of light D. cold temperature E. vibration

The inhibitory neurotransmitters of the CNS, GABA and glycine, act by opening ________ channels. A. only Na+ B. only Cl- C. only K+ D. only Ca2+ Na+ and K+

Which is NOT housed in the medulla oblongata? A. centers for blood pressure control B. centers for control of vomiting C. centers for control of eye movement D. centers for control of breathing E. the pyramids, where tracts cross to the opposite side of the body

In the membrane of a resting nerve cell, when chemically gated Cl- channels open, A. Cl- ions enter the cell. B. Cl- ions leave the cell. C. the cell becomes depolarized. D. Cl- ions enter the cell and the cell becomes depolarized. E. Cl- ions leave the cell and the cell becomes depolarized

Cells that form supportive capsules around cell bodies A. ependymal cells B. astrocytes C. satellite cells D. Schwann cells E. oligodendrocytes F. microglia

Opening a Na+ channel in a non-neural sensory receptor cell would cause that cell to A. depolarize. B. hyperpolarize. C. generate an action potential. D. decrease neurotransmitter release.

Graded potentials can A. only act as signals over short distances. B. only act as signals over long distances. C. only cause or prevent an action potential. D. act as signals over short distances and cause or prevent an action potential. E. act as signals over long distances and cause or prevent an action potential.

Glial cells A. only provide structural and metabolic support. B. only guide neurons during growth and repair. C. only help maintain homeostasis of the brain's extracellular fluid. D. provide structural and metabolic support and help maintain homeostasis of the brain's extracellular fluid. E. All of the answers are correct.

Ion concentrations are first significantly affected after ________ action potential(s). A. one B. a few dozen C. a few hundred D. a few thousand E. a few million

A home satellite dish receives signals from a satellite, allowing your television to display TV shows. Which part of a neuron is analogous to the satellite dish? A. cell body B. dendrites C. axon D. varicosities E. collaterals

swellings containing sensory cell bodies A. dorsal horns B. columns C. ventral root D. dorsal root ganglion E. nuclei

The afferent and efferent axons together form the A. central nervous system. B. autonomic division system. C. somatic motor division of the nervous system. D. peripheral nervous system. E. visceral nervous system.

The following are the main steps in the generation of an action potential: 1. sodium channels are inactivated 2. more voltage-regulated potassium channels open and potassium moves out of the cell, initiating repolarization 3. sodium channels regain their normal properties 4. a graded depolarization brings an area of an excitable membrane to threshold 5. a temporary hyperpolarization occurs 6. sodium channel activation occurs 7. sodium ions enter the cell and further depolarization occurs The proper sequence of these events is A. 4, 6, 7, 3, 2, 5, 1. B. 4, 6, 7, 1, 2, 5, 3. C. 6, 7, 4, 1, 2, 3, 5. D. 2, 4, 6, 7, 1, 3, 5. E. 4, 2, 5, 6, 7, 3, 1.

Originate(s) at the trigger zone A. graded potential B. action potential C. both

Result(s) from influx of sodium A. graded potential B. action potential C. both

Which of these has a higher concentration in cerebrospinal fluid than in the blood? A. K+ B. H+ C. Ca2+ D. HCO3- E. Na+

Which of the following is the most common location where action potentials originate? A. Dendrites B. cell body C. axon hillock D. synaptic cleft E. synaptic bouton

Match the stimulus to the type of receptor that typically responds to it Stretch A. mechanoreceptor B. chemoreceptor

The brain area(s) that has/have a cortex is/are the A. cerebrum only. B. cerebellum only. C. medulla oblongata only. D. cerebrum and cerebellum. E. cerebrum and medulla oblongata.

The intensity of a stimulus can be determined within the central nervous system by A. population coding only. B. labeled line coding only. C. frequency coding only. D. population coding and/or frequency coding. E. labeled line coding and/or frequency coding.

require(s) a minimum stimulus to occur A. graded potential B. action potential C. both

Choose all of the items that are incorrectly matched. A. inactivation gate - closed at rest B. activation gate - open at rest C. inactivation gate - closed during repolarization D. activation gate - opens during depolarization E. All of the answers are incorrectly matched.

Match the specific receptor to its typical stimulus Texture A. free nerve ending B. Merkel receptor C. Messiner's corpuscle D. Ruffini corpuscle E. Pacinian corpuscle

composed of distinct regions of gray and white matter, a section of the brain that develops with sulci and gyri A. Cerebellum B. Hypothalamus C. Thalamus D. Cerebrum

Match the specific receptor to its typical stimulus Stretch A. free nerve ending B. Merkel receptor C. Messiner's corpuscle D. Ruffini corpuscle E. Pacinian corpuscle

oligodendrocytes A. Central nervous system B. Peripheral nervous system

A chemical synapse ALWAYS includes ________. 1. Axon terminal 2. Presynaptic cell 3. Synaptic cleft 4. Post synaptic cleft 5. Dendrite A. 1, 2, 3, 4, 5 B. 1, 2, 3, 4 C. 2, 3, 4 D. 2, 3, 4, 5 E. 1, 3, 4

Identify the FALSE statement. A. Under normal conditions, all action potentials in a given cell are identical. B. Between nodes of Ranvier, signal conduction is decremental. C. The amplitude of the action potential depends on the amplitude of the graded potential that precedes it. D. The voltage-gated sodium and potassium channels begin to open during the depolarization

When more action potentials arrive at the axon terminal, how is the postsynaptic cell affected? A. Neurotransmitter release increases, but does not change the graded potentials that follow. B. Neurotransmitter release does not change, thus the postsynaptic cell behaves the same way it always behaves. C. Neurotransmitter release increases, thereby increasing the frequency or magnitude of graded potentials in the postsynaptic cell. D. Neurotransmitter release does not change, but voltages applied to the postsynaptic cell increase.

In the first phase of triggering an action potential in a neuron, Na+ ions flow in and A. only trigger a negative feedback loop. B. only trigger a positive feedback loop. C. only activate the sodium/potassium pump. D. trigger a negative feedback loop and activate the sodium/potassium pump. E. trigger a positive feedback loop and activate the sodium/potassium pump.

The absolute refractory period of an action potential A. only ensures one-way travel down an axon. B. only allows a neuron to ignore a second signal sent that closely follows the first. C. only prevents summation of action potentials. D. ensures one-way travel down an axon and allows a neuron to ignore a second signal sent that closely follows the first. E. ensures one-way travel down an axon, allows a neuron to ignore a second signal sent that closely follows the first, and prevents summation of action potentials.

The rearrangement of connections at synapses, which occurs throughout life, is termed A. elasticity. B. intelligence. C. plasticity. D. senility. E. synchronicity.

small area that relays signals for auditory and visual reflexes as well as eye movement A. Medulla oblongata B. Pons C. Midbrain D. Reticular formation

The brain's interpretation of sensory stimuli is called A. proprioception. B. perception. C. cognition. D. lateralization. E. emotion.

Caffeine, nicotine, and alcohol all have effects on A. action potential conduction. B. long-term potentiation. C. synaptic activity. D. neurotransmitter degradation. E. neurotransmitter reuptake.

Experimental animals become tamer and more sexually active following damage to the A. amygdala. B. hippocampus. C. suprachiamatic nucleus. D. hypothalamus. E. corpus callosum

The inactivation gate A. quickly opens and closes after depolarization. B. is coupled to the movement of the activation gate, but is much slower. C. depends on a change of +100 mV from rest to be signaled to close. D. depends on a loss of Na+ permeability to be triggered. E. depends on a loss of K+ permeability to be triggered.

The structure that connects the two cerebral hemispheres is the A. basal nuclei. B. suprachiasmatic nucleus. C. corpus callosum. D. hippocampus. E. gray "H."

Repair of damaged neurons can be assisted by certain neurotrophic factors secreted by the A. cell body only. B. axon only. C. dendrites only. D. Schwann cells only. E. axon and dendrites

relay station for transfer of information between the cerebrum and cerebellum; coordinates breathing control with other areas A. Medulla oblongata B. Pons C. Midbrain D. Reticular formation

The collection of axons that carries information between the central nervous system and the peripheral effectors is called the A. axon hillock. B. varicosity. C. axon. D. dendrite. E. nerve.

Match the stimulus to the type of receptor that typically responds to it pH a. Chemoreceptor b. Mechanoreceptor

Network to coordinate arousal and sleep, but also involved in blood pressure regulation and pain modulation A. Medulla oblongata B. Pons C. Midbrain D. Reticular formation

The tip of an embryonic nerve cell's axon is called a A. kissing cone. B. stem tip. C. growth cone. D. growth tip. E. None of the answers are correct.

Which is/are the most common inhibitory neurotransmitter(s) of the CNS? A. GABA only B. glycine only C. glutamate only D. GABA and glycine E. All of the answers are correct.

Tetrodotoxin is a toxin that blocks voltage-gated sodium channels. What effect does this substance have on the function of neurons? A. Neurons depolarize more rapidly. B. Action potentials lack a repolarization phase. C. The absolute refractory period is shorter than normal. D. The neuron is not able to propagate action potentials. E. The toxin does not interfere with neuron function because the voltage-regulated sodium channels would still function.

Match the type of receptor with the appropriate description The most studied examples of this type are phasic receptors called Pacinian corpuscles. A. Chemoreceptors B. Touch receptors C. Thermoreceptors D. nociceptors

Action potentials are primarily associated with the membranes of A. dendrites only. B. cell bodies only. C. axons only. D. dendrites and axons. E. cell bodies and axons.

Inhibitory postsynaptic potentials (IPSPs ) A. result in local depolarizations. B. result in local hyperpolarizations. C. increase membrane permeability to sodium ions. D. prevent the escape of potassium ions. E. prevent the escape of calcium ions.

Match these terms with their descriptions myelinated axons with very few cell bodies A. grey matter B. white matter C. ascending tracts D. descending tracts E. propriospinal tracts

Match the part of the neuron to its description may be covered with myelin A. dendrites B. cell body C. axon

Match the term with its description cells that myelinate only one axon each; multiple cells per axon A. ependymal cells B. astrocytes C. satellite cells D. Schwann cells E. oligiodendrocytes F. Microglia

Match the glial cell to the nervous system division in which it is found satellite cells A. Central nervous system B. peripheral nervous system

The pattern of synaptic connectivity where a large number of presynaptic neurons provide input to a single postsynaptic neuron, is known as A. divergence. B. convergence. C. integration. D. saltatory conduction. E. potentiation.

The site of information integration in the nervous system is the A. chemical synapse. B. electrical synapse. C. trigger zone. D. dendritic membrane. E. axon terminal

Tonic receptors A. are quick to adapt to a particular stimulus intensity. B. slowly decrease the frequency of action potentials generated to a constant stimulus. C. are attune to changes in a parameter, not the extent of that change. D. will always decrease to the point where no action potentials are generated.

For the structures listed below, choose one of the following Cerebral Cortex A. structure composed of grey matter B structure composed of white matter

Convergence describes A. the reason why receptive fields are so small. B. how one primary sensory receptor neurons synapses with a secondary neuron. C. how multiple primary sensory neurons synapse on a single secondary neuron. D. how receptive fields can overlap with one another.

Match the term with its description Cells in the CNS that form myelin A. ependymal cells B. astrocytes C. satellite cells D. Schwann cells E. oligiodendrocytes F. Microglia

These glial cells act as scavengers. A. Schwann cells B. astrocytes C. microglia D. oligodendrocytes E. ependymal cells

Cell bodies of sensory neurons are located in A. propriospinal tracts. B. ventral root ganglia. C. ventral horns. D. dorsal horns. E. dorsal root ganglia.

Which of the following would be an adequate stimulus for a mechanoreceptor? A. oxygen B. cell stretch C. photon of light D. cold temperature E. pH

A receptor potential is A. an action potential. B. a graded potential. C. the resting membrane potential of a receptor cell. E. always converted to an action potential in sensory receptor cells.

Match the type of receptor with the appropriate description. These receptors slowly adapt, and would be activated when the skin is between A. Chemoreceptors B. Touch receptors C. Thermoreceptors D. nociceptors

These CNS glial cells may be a source of treatment for neural degenerative disorders. A. Schwann cells B. astrocytes C. microglia D. oligodendrocytes E. ependymal cells

The neurotransmitter thought to be involved in learning and memory is A. norepinephrine. B. glutamate. C. acetylcholine. D. GABA. E. glycine.

These glial cells may contribute to Lou Gehrig's disease. A. Schwann cells B. astrocytes C. microglia D. oligodendrocytes E. ependymal cells

You used to love to drink milk when you were a child. Lately, you notice that your stomach hurts and you experience bloating and discomfort when you drink it. It is no longer inviting when you see someone else drinking it. What kind of learning has occurred? A. associative B. anterograde C. habituation D. sensitization

Which statement regarding the hypothalamus is FALSE? A. Hypothalamic trophic factors control the release of anterior pituitary hormones. B. It receives input from multiple sources. C. It receives sensory fibers from the optic tract, ears, and spinal cord. D. The hypothalamus contains various centers for behavioral drives such as hunger and thirst.

Which of the following are responsible for a receptor adapting to a stimulus? A. K+ channel inactivation only B. Na+ channel inactivation only C. opening of Na+ channels only D. opening of K+ channels only E. Na+ channel inactivation or K+ channel opening

Match the part of the neuron to its description Where most graded potentials originate A. dendrites B. axon C. cell body

Match these terms with their descriptions. Projections of white matter that remain in the spinal cord A. grey matter B. white matter C. ascending tracts D. descending tracts E. propriospinal tracts

Beta-endorphin is produced from the same prohormone as A. adrenocorticotropin (ACTH). B. insulin. C. aldosterone. D. thyroxine. E. glucagon.

Match the part of the neuron to its description Occupy(ies) the least amount of cell volume A. dendrites B. axon C. cell body

Match the type of receptor with the appropriate description These receptors respond to stimuli that are harmful or potentially harmful to body tissues and lead to the perception of pain. A. Chemoreceptors B. Touch receptors C. Thermoreceptors D. nociceptors

Which of the following is NOT a somatosensory modality? A. proprioception B. touch C. vision D. nociception E. temperature

In general, the nervous system is composed of which two types of cells? 1. Motor 2. neurons 3. sensory 4. glial 5. assiociated A. 1 and 2 B. 1 and 3 C. 2 and 4 D. 3 and 4 E. 3 and 5

Match these brain areas with their locations. temporal lobe A. primary somatic sensory cortex B. visual cortex C. auditory cortex D. association areas

Match the part of the neuron to its description contribute(s) most to membrane surface area of cell A. dendrites B. axon C. cell body

A molecule that prevents substance P from binding to its receptor would A. stimulate a painful sensation. B. reduce the perception of pain. C. the perception of hot and cold stimuli. D. interfere with transduction from chemoreceptors. E. heighten the perception of touch.

Once the action potential reaches the axon terminal, what happens next? A. exocytosis of a neurocrine B. release of the neurotransmitter into the synaptic cleft C. release of a neurohormone into the blood D. Any of these could happen next.

Match the specific receptor to its typical stimulus. vibration A. free nerve ending B. Merkel receptor C. Meissner's corpuscle D. Ruffini corpuscle E. Pacinian corpuscle

The rising phase of the action potential is due to A. Na+ flow into the cell only. B. Na+ flow out of the cell only. C. K+ flow out of the cell only. D. K+ flow into the cell only. E. Na+ flow out of the cell and K+ flow into the cell.

During the relative refractory period, an initial threshold-level depolarization is usually not sufficient to trigger an action potential. Why? A. Only some Na+ channels have returned to their resting position. B. Only K+ channels are still open, so Na+ entry is offset by K+ loss. C. Only a few K+ channels have returned to their resting position. D. The statement is incorrect; a threshold-level depolarization always triggers an action potential. E. Some Na+ channels have returned to their resting position and K+ channels are still open, so Na+ entry is offset by K+ loss.

The internal clock of mammals appears to be located in the A. suprachiasmatic nucleus. B. pituitary gland. C. choroid plexus. D. pons. E. brain stem.

Enhancement of the postsynaptic cell's response to a repeated stimulus is called A. training. B. learning. C. reflexation. D. facilitation. E. consolidation.

For the structures listed below, choose one of the following limbic system A. a structure composed of grey matter B. a structure composed of white matter

Match these brain areas with their locations all lobes A. primary somatic sensory cortex B. visual cortex C. auditory cortex D. association areas

A graded change in membrane potential within a sensory receptor cell is always called a(n) A. depolarization. B. hyperpolarization. C. action potential. D. receptor potential.

Identify the FALSE statement regarding sensory receptor cells. A. Threshold is the minimal stimulus intensity required to generate an action potential. B. Sensory transduction converts stimulus energy into a receptor potential. C. Each type of sensory receptor responds only to the stimulus that defines the receptor. D. A graded potential is referred to as a receptor potential. E.Many sensory receptor cells are NOT nerve cells.

Language and verbal skills tend to be ________ side of the brain of right-handed people. A. concentrated on the left B. concentrated on the right C. equally distributed between the left and right D. randomly located with respect to the left or right

Sharp, localized (fast) pain is rapidly transmitted to the central nervous system along A. large, unmyelinated C fibers. B. small, myelinated A-delta fibers. C. small, unmyelinated C fibers. D. large, myelinated A-beta fibers.

Match the part of the neuron to its description receive(s) most of the incoming synapses A. dendrites B. axon C. cell body

Interneurons are found A. only in the brain. B. only in the spinal cord. C. only in the CNS. D. throughout the nervous system. E. only in spinal nerves.

Which of these roles is NOT related to the reticular formation? A. arousal and sleep B. muscle tone and stretch reflexes C. pain modulation D. blood pressure regulation E. regulation of the menstrual cycle

Phasic receptors A. quick to adapt to a particular stimulus intensity. B. slowly decrease the frequency of action potentials generated to a constant stimulus. C. attune to parameters that the body must continuously assess. D. once threshold is reached by a stimulus will always generate action potentials.

In order for a synapse to be an effective means of cellular communication, slow removal or inactivation of neurotransmitter molecules from the synapse is important. A. True B. False

The modality of a stimulus can be determined within the central nervous system by A. population coding. B. lateral inhibition. C. frequency coding. D. adequate stimulus for the sensory receptor cell.

Clusters of nerve cell bodies in the peripheral nervous system are called A. microglia. B. neuroglia. C. glia. D. ganglia. E. nodes.

Voltage-regulated channels are located A. within the cytosol only. B. in the membranes of dendrites only. C. in the membranes of axons only. D. on the neuron cell body only. E. in the membranes of dendrites, in the membranes of axons, and on the neuron cell body.

These are probably the oldest sensory receptors as evidenced by their existence in primitive animals that do not have formalized nervous systems. A. Chemoreceptors B. Touch receptors C. Thermoreceptors D. nociceptors

Match these functions with the correct brain area. contains corticospinal tracts, the pyramids, and control centers for breathing, swallowing, and blood pressure A. Medulla oblongata B. Pons C. Midbrain D. Reticular formation

In addition to temperature, cold receptors respond to A. menthol. B. capsaicin. C. alcohol. D. water.

For the structures listed below, choose one of the following Ventral horn A. structure composed of grey matter B. structure composed of white matter

The axon is connected to the cell body by the A. myelin sheath. B. axon terminal. C. collaterals. D. axon hillock. E. synapse.

Match these terms with their descriptions myelinated axons with very few cell bodies A. grey matter B. white matter C. ascending tracts D. descending tracts E. propriospinal tracts

The perception threshold describes the A. intensity of stimulus required to generate a receptor potential. B. intensity of stimulus required to generate an action potential. C. convergence of information from multiple primary sensory neuron onto a single secondary neuron. D. concept that neurons higher in the sensory pathway can dampen the intensity of a stimulus.

When the neuron is at rest, which statement is true? A. The activation gate is closed. B. The inactivation gate is open. C. No Na+ crosses the membrane is the only observation. D. The activation gate is closed and the inactivation gate is open. E. The activation gate is closed and no Na+ crosses the membrane.

Chronic pain is A. only pathological. B. only treated by analgesic drugs. C. only the result of short-term changes in the nervous system D. pathological and treated by analgesic drugs.

Match the part of the neuron to its description supported by satellite cells A. dendrites B. axon C. cell body

Information coming into the central nervous system is transmitted along ________ neurons. A. afferent B. sensory C. efferent D. afferent and sensory E. sensory and efferent

The portions of a neuron that extend off of the roughly spherical cell body are usually collectively called A. protrusions. B. processes. C. prostheses. D. projections.

For the structures listed below, choose one of the following: Basal ganglia A. structure composed of grey matter B. structure composed of white matter

All of the following must occur before a second action potential can begin, EXCEPT A. the Na+ and K+ ions that moved in/out of the cell must move back to their original compartments. B. the Na+ inactivation gate must open and the Na+ activation gate must close. C. the absolute refractory period must occur. D. the Na+ and K+ ions that moved in/out of the cell must move back to their original compartments; the Na+ inactivation gate must open; and the Na+ activation gate must close. E. None of the answers are correct.

The inability to remember newly acquired information is called A. discombobulation. B. anterograde amnesia. C. term amnesia. D. implicit amnesia. E. retrograde amnesia.

A decrease in ones perception of a stimulus whose intensity has not changed due to higher neural inhibition is A. habituation. B. convergence. C. divergence. D. adaptation.

Receives sensory input from the inner ear's receptors for equilibrium and balance A. cerebellum B. hypothalamus C. thalamus D. cerebrum

The basis of neural integration is A. addition of postsynaptic potentials overlapping in time and space. B. command signals from central pattern generators. C. spontaneous activity in pacemaker neurons. D. the area under the curve of postsynaptic potentials overlapping in time and space.

Match these terms with their descriptions. tracts of axons that transfer information to and from the brain A. dorsal horns B. columns C. ventral root D. dorsal root ganglia E. nuclei

Reasoning arises in the outer layer of neurons of which of the following? A. hippocampus B. amygdala C. basal nuclei D. cerebral cortex E. amygdala and hippocampus

A complete spinal cord transection injury results in paralysis, which is the inability to do which of the following? A. move voluntarily B. move at all C. feel D. move voluntarily and feel E. move at all and feel

The brain consumes about half of the ________ circulating in the body. A. oxygen B. glucose C. sodium D. potassium E. fatty acids

How would the absolute refractory period be affected if voltage-gated sodium channels remained inactivated? A. It would be longer than normal. B. It would be shorter than normal. C. It would be the same whether the channels remained inactivated or not. D. None of the answers are correct.

To increase the amount of neurotransmitter released onto a postsynaptic cell, the presynaptic cell would have to A. send action potentials with higher voltage (higher amplitude). B. send action potentials with longer durations. C. send action potentials with higher frequency. D. do nothing; no change is possible since the all-or-none law is in effect.

When sodium channels open during an action potential, the opening is caused by A. binding of sodium ions. B. binding of potassium ions. C. presence of calcium. D. presence of positive charge.

Neuronal cells that are short-lived and therefore are frequently replaced are A. gustatory receptors. B. nociceptors. C. Pacinian corpuscles. D. olfactory receptors. E. retinal cells.

The multiple thin, branched structures on a neuron whose main function is to receive incoming signals are the A. cell bodies. B. axons. C. dendrites. D. somata. E. None of the answers are correct.

Match these terms with their descriptions. motor fibers leave the spinal cord's gray matter via this A. dorsal horns B. columns C. ventral root D. dorsal root ganglia E. nuclei

Presynaptic facilitation occurs when A. extracellular concentration of sodium increases. B. extracellular concentration of potassium increases. C. calcium channels in the presynaptic membrane are inhibited. D. calcium channels in the presynaptic membrane remain open longer. E. temporal summation occurs.

An enhancement of the postsynaptic cell's response to a constant stimulus that lasts for a period of time from hours to weeks is called A. training. B. consolidation. C. long-term potentiation. D. synchronicity. E. synaptic plasticity.

Some neurotoxins work essentially the same way as some local anesthetics, which is to A. inactivate the enzyme that destroys the neurotransmitter only. B. bind to Na+ channels and inactivate them only. C. prevent depolarization by blocking Na+ entry into the cell only. D. inactivate the enzyme that destroys the neurotransmitter and bind to Na+ channels and inactivate them. E. bind to Na+ channels and inactivate them and prevent depolarization by blocking Na+ entry into the cell.

If a stimulating electrode is placed in the middle of a resting axon and an above-threshold voltage is applied to the electrode action potentials A. will not occur. B. will start at that point and proceed only toward the axon terminal. C. will start at that point and proceed only toward the cell body. D. will start at that point and travel in both directions in the axon.

Nociceptors are responsible for the perception of A. pain only. B. skin stretch only. C. itch only. D. pain and itch. E. pain and skin stretch.

An excitatory postsynaptic potential (EPSP) A. depolarizes a neuron, decreasing the likelihood of an action potential. B. hyperpolarizes a neuron, decreasing the likelihood of an action potential. C. depolarizes a neuron, increasing the likelihood of an action potential. D. hyperpolarizes a neuron, increasing the likelihood of an action potential.

Substances that have been isolated from the blood and have been shown to induce sleep have also been linked to the ________ system. A. urinary B. respiratory C. reproductive D. integumentary E. immune

Which ion(s) is/are higher in concentration inside the cell compared to outside? A. potassium B. sodium C. chloride D. calcium E. More than one of the answers is correct.

The all-or-none principle states that A. all stimuli will produce identical action potentials. B. all stimuli great enough to bring the membrane to threshold will produce action potentials of identical magnitude. C. the greater the magnitude of the stimuli, the greater the intensity of the action potential. D. only sensory stimuli can activate action potentials. E. only motor stimuli can activate action potentials.

General anesthetics keep surgical patients unconscious by reducing activity in the A. hippocampus. B. corpus callosum. C. lateral ventricles. D. reticular formation. E. medullary pyramids

If the resting axon's membrane becomes more permeable to potassium ions, A. the inside of the membrane will become more positively charged. B. the membrane will depolarize more rapidly. C. it will take a stimulus of larger magnitude to initiate an action potential. D. the hyperpolarization at the end of the action potential will not occur.

When two or more graded potentials arrive at the trigger zone, which of the following could happen? A. An excitatory and inhibitory signal can cancel each other out. B. Two excitatory stimuli may be additive, and summation could occur. C. Two inhibitory stimuli may be additive, resulting in lower excitability. D. An excitatory and inhibitory signal can cancel each other out and two excitatory stimuli may be additive, and summation could occur. E. An excitatory and inhibitory signal can cancel each other out; two excitatory stimuli may be additive, and summation could occur; and two inhibitory stimuli may be additive, resulting in lower excitability.

The mixed cranial nerve that projects to and from internal organs, muscles, and glands is the ________ nerve. A. trochlear B. spinal accessory C. trigeminal D. vagus E. glossopharyngeal

An important structure in both learning and memory is the A. cerebellum. B. pons. C. medulla. D. hippocampus. E. hypothalamus.

Sensory neurons that maintain their firing as long as the stimulus is present are called ________.

The tactile receptor whose nerve endings are surrounded by concentric connective tissue layers is the A. Ruffini corpuscle. B. Pacinian corpuscle. C. Meissner's corpuscle. D. Merkel disc. E. root hair plexus.

The falling phase of the action potential is due primarily to A. Na+ flow in the cell only. B. Na+ flow out of the cell only. C. K+ flow out of the cell only. D. K+ flow into the cell only. E. Na+ flow out of the cell and K+ flow into the cell.

The gate control theory of pain modulation states that pain transmission can be blocked by A. cold stimulation of the A-delta fibers. B. mechanical stimulation of A-beta fibers. C. stimulation of C-fibers. D. tonic activity of the inhibitory neurons in the dorsal horn.

Exocrine glands, smooth muscles, and cardiac muscles are controlled by the A. central nervous system. B. autonomic nervous system. C. somatic motor division. D. peripheral nervous system. E. enteric nervous system.

Cerebrospinal fluid is produced by the A. choroid plexus. B. arachnoid villi. C. frontal sinuses. D. pia mater. E. ventricles.

In order to signal a stronger stimulus, action potentials become A. higher in amplitude only. B. more frequent only. C. longer-lasting only. D. higher in amplitude and more frequent. E. higher in amplitude and longer-lasting.

In response to binding a neurotransmitter, a postsynaptic cell can A. only open chemically gated ion channels, causing graded potentials known as fast synaptic potentials. B. only close ion channels via G proteins and second messenger systems, producing slow responses. C. only regulate protein synthesis and affect the metabolic activities of the postsynaptic cell. D. open chemically gated ion channels, causing graded potentials known as fast synaptic potentials and regulate protein synthesis and affect the metabolic activities of the postsynaptic cell. E. open chemically gated ion channels, causing graded potentials known as fast synaptic potentials, close ion channels via G proteins and second messenger systems, producing slow responses, and regulate protein synthesis and affect the metabolic activities of the postsynaptic cell.

If the sodium-potassium pumps in the cell membrane of a neuron fail to function, over time A. the extracellular concentration of potassium ion will increase. B. the intracellular concentration of sodium ion will increase. C. the membrane resting potential will become more positive than normal. D. All of the answers are correct.

The term hyperkalemia specifically indicates too much potassium in which fluid compartment? A. blood B. intracellular C. interstitial D. extracellular E. All of the answers are correct.

The enteric nervous system is a network of neurons that function in controlling A. reproduction. B. digestion. C. excretion, particularly urination. D. the skeletal system. E. the endocrine system.

Identify the FALSE statement regarding sensory receptor cells. A. Threshold is the minimal stimulus intensity required to generate an action potential. B. Sensory transduction converts stimulus energy into a receptor potential. C. Each type of sensory receptor responds only to the stimulus that defines the receptor. D. A graded potential is referred to as a receptor potential. E. Many sensory receptor cells are NOT nerve cells.

The inhibitory neurotransmitters of the CNS, GABA and glycine, act by opening ________ channels. A. only Na+ B. only Cl- C. only K+ D. only Ca2+ E. Na+ and K+

Symptoms of the fight-or-flight reaction include all of these EXCEPT A. hunger. B. pounding heart. C. sweating palms. D. increased blood pressure. E. pupillary dilation.

Which of these does NOT contribute significantly to the protection of the brain? A. cranium B. subarachnoid space C. cerebrospinal fluid (CSF) D. dura mater E. cerebral space

The primary problem in hyperkalemia is A. that neurons are harder to excite because their resting potential is hyperpolarized. B. that neurons are hyperexcitable because their resting potential is closer to threshold. C. that neurons respond too quickly to smaller graded potentials. D. neurons are harder to excite because their resting potential is hyperpolarized and neurons respond too quickly to smaller graded potentials. E. neurons are hyperexcitable because their resting potential is closer to threshold and neurons respond too quickly to smaller graded potentials.

The resting membrane potential results from A. uneven distribution of ions across the cell membrane only. B. differences in membrane permeability to Na+ and K+ only. C. activity of the sodium/potassium pump only. D. uneven distribution of ions across the cell membrane and differences in membrane permeability to Na+ and K+. E. None of the answers are correct.

Microvilli are present on cells that, because of their function, benefit from an increased membrane surface area. Which structure(s) on a neuron provide a comparable benefit? A. cell body B. dendrites C. axon D. varicosities E. collaterals

Which type of synapse is most prevalent in the nervous system? A. chemical B. electrical C. mechanical D. processing E. radiative

Presynaptic facilitation makes a pathway A. less likely to be in use, just through hyperpolarization of selected neurons. B. more likely to be in use, just through depolarization of selected neurons. C. capable of alteration, just through training and conditioning. D. less likely to be in use, just through hyperpolarization of selected neurons and capable of alteration, just through training and conditioning. E. more likely to be in use, just through depolarization of selected neurons and capable of alteration, just through training and conditioning.

The larger the receptive field, the A. stronger the stimulus intensity required to activate a sensory receptor. B. more primary sensory neurons synapse on a secondary sensory neuron. C. fewer primary sensory neurons are involved. D. larger the area of the somatosensory cortex in the brain that perceives the sensation.

During childhood, growth and development of the brain PRIMARILY occurs by increasing A. neuron numbers only. B. neuron size only. C. number of dendrites and synapses only. D. neuron numbers and neuron size. E. neuron size and number of dendrites and synapses.

Which of the following does NOT influence the time necessary for a nerve impulse to be conveyed by a particular neuron? A. length of the axon B. presence or absence of a myelin sheath C. diameter of the axon D. presence or absence of nodes of Ranvier E. whether axon is sensory or motor

Inhibition of neural activity can result from A. presynaptic events only. B. postsynaptic events only. C. presynaptic events and postsynaptic events.

Which of the following is NOT a known drug effect on synaptic function? A. interfere with neurotransmitter synthesis B. alter the rate of neurotransmitter release C. prevent neurotransmitter inactivation D. prevent neurotransmitter binding to receptors E. change the type of neurotransmitter found in the synaptic vesicle

Sensory receptors that respond when body temperature is below normal are called A. warm receptors. B. photoreceptors. C. cold receptors. D. All receptors respond to temperatures above and below body temperature (no unique name).

Conduction occurs along an axon because A. outflow of K+ triggers the adjacent channels to open. B. inflow of Na+ triggers the adjacent channels to open. C. once Na+ enters the cell, the entire membrane depolarizes simultaneously. D. axonal transport "walks" voltage changes along the membrane.

The cell body of neurons is generally A. 90% of the cell volume. B. 50% of the cell volume. C. 10% of the cell volume. D. found in the same position on every neuron.

The hormone that is released to enhance the fight-or-flight reaction is A. thyroid hormone. B. prolactin. C. oxytocin. D. epinephrine. E. antidiuretic hormone.

Once the stimulus alters the receptor on the cell's membrane, what happens next? A. Ion channels open, allowing ions to enter or exit. B. The membrane permeability is altered. C. A second messenger is activated on the inside of the cell. D. Any of these actions could happen next.

Visceral pain is poorly localized and can be perceived to originate from a region of the body that is different from it's actual location; this is called A. analgesia. B. adaptation. C. referred pain. D. tonic reception. E. latency.

Which brain area is considered to be a key integrating center for homeostasis? A. hypothalamus B. thalamus C. pituitary gland D. brain stem E. medulla

Learning and memory are thought to be due to a synaptic phenomenon known as A. inhibition. B. excitation. C. modulation. D. facilitation. E. long-term potentiation.

When a second EPSP arrives at a single synapse before the effects of the first have disappeared, what occurs? A. spatial summation B. temporal summation C. inhibition of the impulse D. hyperpolarization E. decrease in speed of impulse transmission

With the exception of olfaction, all sensory pathways first travel to the ________, which acts as a relay and processing station. A. cerebrum B. thalamus C. cerebellum D. hypothalamus E. medulla oblongata

Some types of antihistamines make one sleepy, others do not. This difference is partly attributed to a difference in A. lipid solubility. B. the type of receptor involved. C. ATP-dependence of drug transport. D. whether or not the drug mimics the hormone melatonin

When multiple, possibly even conflicting signals reach a neuron, the neuron evaluates the signals and may respond or not. This property is called A. temporal summation. B. spatial summation. C. postsynaptic integration. D. graded potentials. E. EPSPs.

If a hyperpolarizing graded potential and a depolarizing graded potential of similar magnitudes arrive at the trigger zone at the same time, what is most likely to occur? A. An action potential is fired off more quickly than usual. B. Nothing. They will cancel each other out. C. The cell becomes hyperpolarized. D. The cell becomes easier to excite. E. The cell dies.

Which of the following will best increase the conduction rate of action potentials? A. Increase the diameter of the axon, decrease the resistance of the axon membrane to ion leakage. B. Increase the diameter of the axon, increase the resistance of the axon membrane to ion leakage. C. Decrease the diameter of the axon, decrease the resistance of the axon membrane to ion leakage. D. Decrease the diameter of the axon, increase the resistance of the axon membrane to ion leakage.

Neurotransmitter is stored and released from A. axon terminals only. B. axon varicosities only. C. dendritic spines only. D. cell bodies only. E. axon terminals and axon varicosities.

The collection of axons that carries information between the central nervous system and the peripheral effectors is called the A. axon hillock. B. varicosity. C. axon. D. dendrite. E. nerve.

The brain has a ________ (high or low?) demand for oxygen, and receives about ________% of the total blood volume in circulation. A. high; 35 B. low; 35 C. low; 15 D. high; 15 E. high; 50

The region where the axon terminal meets its target cell is called the A. collateral. B. hillock. C. synapse. D. nerve. E. dendrites.

Chemicals such as histamine, prostaglandins, serotonin, and substance P A. only sensitize nociceptors. B. only activate nociceptors. C. only inhibit nociceptors. D. only sensitize and activate nociceptors. E. sensitize, activate and inhibit nociceptors

The ion necessary to initiate the release of acetylcholine into the synaptic cleft is sodium. potassium. calcium. chloride. zinc.

A damaged neuron has a better chance of survival and repair if the ________ is/are undamaged. A. cell body B. axon C. dendrites D. Schwann cells E. axon and dendrites

The major determinant of the resting potential of all cells is A. Ca2+ concentration in the blood and interstitial fluid. B. Na+ concentration in the blood and interstitial fluid. C. K+ gradient between the blood and interstitial fluid. D. K+ concentration inside cells. E. Na+ concentration inside cells.

Tom's father suffers a stroke that leaves him partially paralyzed on his right side. What type of glial cell would you expect to find in increased numbers in the damaged area of the brain that is affected by the stroke? A. astrocytes B. Schwann cells C. oligodendrocytes D. microglia

When voltage-gated K+ channels of a resting neuron open, A. K+ enters the neuron. B. K+ leaves the neuron. C. the neuron depolarizes. D. K+ enters the neuron and the neuron depolarizes. E. K+ leaves the neuron and the neuron depolarizes.

Which functions in the control of movement? A. hippocampus only B. amygdala only C. basal nuclei only D. hippocampus and amygdala E. All of these function in the control of movement.

When comparing action potentials to graded potentials, an/two important distinguishing characteristic/s is/are A. graded potentials can undergo summation. B. action potentials can undergo summation. C. that the rate of action potentials is limited by the refractory period. D. graded potentials can undergo summation and the rate of action potentials is limited by the refractory period. E. action potentials can undergo summation and the rate of action potentials is limited by the refractory period.

Caffeine and related stimulants exert their effects by A. mimicking a specific neurotransmitter. B. inhibiting a specific neurotransmitter. C. mimicking a specific neuromodulator. D. inhibiting a specific neuromodulator.

Calcium is important in the synapse because it A. is necessary for acetylcholine synthesis. B. signals the exocytosis of the neurotransmitter. C. binds to receptors on the postsynaptic cell, opening ion channels, and triggering graded potentials. D. leaves the axon terminal, hyperpolarizing the cell.

The ion necessary to initiate the release of acetylcholine into the synaptic cleft is A. sodium. B. potassium. C. calcium. D. chloride. E. zinc.

Conduction speed is (or can be) enhanced by A. myelin. B. altering extracellular sodium concentration. C. increasing the temperature. D. altering extracellular potassium concentration. E. myelin and increasing the temperature.

Chemicals such as histamine, prostaglandins, serotonin, and substance P A. only sensitize nociceptors. B. only activate nociceptors. C. only inhibit nociceptors. D. only sensitize and activate nociceptors. E. sensitize, activate and inhibit nociceptors.