Chapter 7

A bundle of axons in the CNS is called a/an A. nerve. B. bundle. C. tract. D. neuron.

C

The brain produces lipid neurotransmitters called A. endocannabinoids. B. endorphins. C. enkephalins. D. nitric oxide.

A

The mesolimbic dopamine neurons arise in the midbrain and terminate in the A. nucleus accumbens. B. corpus striatum. C. basal nuclei. D. corpus callosum.

A

The most abundant neuropeptide in the brain is A. neuropeptide Y. B. neuropeptide Z. C. substance P. D. CCK.

A

The most numerous of all cells of CNS nervous tissue are the A. astrocytes. B. neurons. C. Schwann cells. D. microglia

A

The myelin sheaths of PNS neurons are produced by A. Schwann cells. B. oligodendrocytes. C. ependymal cells. D. leukocytes.

A

Gliotransmitters A. include calcium ions. B. can stimulate neurons. C. form the blood-brain barrier. D. break down ATP.

B

Ion channels that open in response to depolarization are called A. ion-gated channels. B. voltage-gated channels. C. stimulation-gated channels. D. potential-gated channels.

B

MAO inhibitors may cause hypertensive crisis by a person eating foods rich in A. phenylalanine. B. tyramine. C. glutamic acid. D. tryptophan.

B

Muscarinic ACh receptors act through ____________ activation of K+ channels. A. cGMP B. G-protein C. M-protein D. ATP

B

Neurotransmitter release would be inhibited by A. stimulating repolarization of the axon terminal. B. blocking Ca2+ influx in the axon terminal. C. blocking repolarization of the axon terminal. D. stimulating protein kinase activity.

B

Nitric oxide A. is a chemical messenger activating adenylate cyclase. B. stimulates the dilation of blood vessels. C. is produced from L-asparagine. D. All apply.

B

Repolarization is accomplished through a A. positive feedback loop. B. negative feedback loop. C. relative refractory loop. D. sodium equilibrium potential.

B

Sensory neurons A. are multipolar and carry impulses toward the CNS. B. are pseudounipolar and carry impulses toward the CNS. C. are bipolar and carry impulses away from the CNS. D. are multipolar and carry impulses away from the CNS.

B

What is the predominant affect of stimulation of nicotinic-gated channels? A. stimulation due to outflow of K+ ions B. inhibition due to outflow of K+ ions C. stimulation due to influx of Na+ ions D. inhibition due to influx of Cl- ions

C

What process is needed to return a membrane to its resting membrane potential with all ions in the correct locations? A. after-hyperpolarization B. all-or-none-law C. Na+/K+ pump D. refractory period

C

What structure is found around PNS axons that is NOT found around CNS axons? A. nodes of Ranvier B. myelin sheath C. neurilemma D. plasma membrane

C

What type of neural pathway involves one neuron forming synapses with several postsynaptic neurons? A. convergent B. oscillating C. divergent D. plastic

C

What type of receptors will bind ATP and adenosine? A. cotransmitter receptors B. pyrimenergic receptors. C. purinergic receptors. D. None apply.

C

Where is glycine released? A. in the PNS B. at skeletal muscleds C. in the CNS D. at the diaphragm

C

Which cells are needed for the formation of synapses in the CNS? A. ependymal B. microglia C. astrocytes D. dendrites

C

Which division of the nervous system innervates involuntary effectors? A. central nervous system B. somatic nervous system C. autonomic nervous system D. associative nervous system

C

Which ion's movements is responsible for repolarization? A. influx of K+ B. influx of Na+ C. outward diffusion of K+ D. outward diffusion of Na+

C

Which of the following is NOT a functional classification of neurons? A. motor neuron B. bipolar neuron C. multipolar neuron D. pseudounipolar neuron

C

Which of the following is NOT an action needed for glutamate to open ion channels? A. NMDA receptor must bind to glycine B. the membrane must be partially depolarized from the action of a different neurotransmitter C. Cl- must pass through the open channel D. Mg2+ is released from NMDA channel to open it

C

Which of the following is NOT classified as a catecholamine? A. norepinephrine B. epinephrine C. histamine D. dopamine

C

Which of the following is NOT true of EPSPs? A. they are graded responses B. they are capable of summation C. they have a refractory period D. they are initiated by neurotransmitters

C

Which of the following is NOT true of axonal transport? A. uses molecular motors B. can transport anterograde or retrograde C. has one fast and two slow components D. is a passive process

D

Postsynaptic inhibition is caused by A. acetylcholine B. GABA C. glycine D. GABA and glycine

D

The average resting membrane potential of an axon is A. -70mV. B. -85mV. C. 0 mV D. +30mV.

A

The brain and spinal cord comprise the A. central nervous system. B. peripheral nervous system. C. peripheral ganglia. D. spinal nerves.

A

Addictive drugs, as well as nicotine, activate dopamine release in the A. nucleus accumbens. B. corpus striatum. C. basal nuclei. D. corpus callosum.

A

An axon will depolarize only if the membrane potential reaches between -70mV and -55mV. This follows the A. All-or-none law. B. recruitment law. C. graduated law. D. threshold law.

A

Benzodiazepines act by increasing ________ activity. A. GABA B. glutamate C. ACh D. enkephalin

A

Botulism toxin prevents release of ACh, causing A. flaccid paralysis. B. hemiplegia. C. spastic paralysis. D. None apply.

A

Chemical synapses A. have a delayed impulse transmission. B. utilize gap junctions. C. occur when two nerve cells are in direct contact with each other. D. do not require the release of neurotransmitters.

A

Enhancing the excitability of a synapse so that transmission is favored along certain pathways is called A. long-term potentiation. B. synaptic plasticity. C. excitotoxicity. D. summation.

A

Muscarinic ACh receptors are found in all of the following locations EXCEPT A. skeletal muscle B. smooth muscle C. cardiac muscle D. glands

A

Regeneration of CNS axons may be prevented in part by inhibitory proteins in the membranes of the A. myelin sheath. B. neurons. C. astrocytes. D. satellite cells.

A

Relaxation of cerebral blood vessels would be stimulated by excessive ________ activity. A. nitric oxide B. acetylcholine C. norepinephrine D. glutamate

A

Temporal summation A. occurs when a single neuron releases neurotransmitter rapidly. B. occurs because of the convergence of many neurons on a single postsynaptic cell. C. only involves excitatory postsynaptic potentials. D. only involves inhibitory postsynaptic potentials.

A

What is NOT true of the relative refractory period? A. Na+ channels are inactivated B. many Na+ channels are returning to a closed state C. K+ is moving out of the axon through its open channels D. a strong stimulus could cause a depolarization

A

What is present at the axon hillock that allows the production of action potentials? A. voltage-gated channels B. ligand-gated channels C. muscarinic receptors D. chemical-gated channels

A

What is the action of the binding of muscarine to its receptors in the digestive system? A. alpha subunits bind to K+ channels, close them, leading to depolarization. B. alpha subunits bind to K+ channels, open them, leading to hyperpolarization. C. beta-gamma subunits bind to K+ channels, close them, leading to depolarization. D. beta-gamma subunits bind to K+ channels, open them, leading to hyperpolarization.

A

What medication acts by increasing the action of nitric oxide as a treatment for erectile dysfunction? A. Viagra B. marijuana C. Prozac D. naloxone

A

What neurotransmitter is used by neurons with cell bodies in the raphe nuclei along the midline of the brainstem? A. serotonin B. dopamine C. glycine D. GABA

A

What type of autonomic fibers release ACh at effectors? A. parasympathetic B. sympathetic C. somatic D. sensory

A

What type of proteins are present in gap junctions that form water-filled channels between neurons? A. connexins B. myelin C. terminal boutons D. cell adhesion molecules (CAMs)

A

Which of the following is NOT a structural classification of neurons? A. motor neuron B. bipolar neuron C. multipolar neuron D. pseudounipolar neuron

A

Which of the following is NOT true of dendrites? A. transmits action potentials toward the cell body B. are thin extensions of the cell body C. transmit graded electrochemical impulses toward the cell body D. contain receptive areas

A

Which of the following is NOT true of long-term potentiation (LTP)? A. Associated with the removal of AMPA glutamate receptors B. Repeated stimulation enhance excitability C. Associated with insertion of AMPA glutamate receptors D. It is a form of synaptic plasticity

A

Which poison inhibits glycine receptors? A. strychnine B. curare C. tetrodotoxin D. All of the choices are correct.

A

Which type of cell of the CNS is phagocytotic? A. microglia B. satellite cells C. ependymal cells D. oligodendrocytes

A

White matter is A. myelinated axons in the CNS. B. myelinated axons in the PNS. C. nonmyelinated cell bodies and dendrites in the CNS. D. nonmyelinated axons in the CNS.

A

______ synapses occur between axons of presynaptic cells and dendrites of postynaptic cells. A. Axodendritic B. Axosomatic C. Myoneural D. Axoaxonic

A

____________ is an acetylcholinesterase antagonist used to treat myasthenia gravis. A. Neostigmine B. Muscarine C. Naloxone D. Nitric oxide

A

Excitotoxicity is caused by A. insufficient synaptic release of glutamate. B. excessive synaptic release of glutamate. C. GABA inhibition. D. insufficient synaptic release of ACh.

B

Acetylcholine can induce hyperpolarization by A. binding to nicotinic receptors. B. binding to muscarinic receptors. C. binding to α-adrenergic receptors. D. binding to β-adrenergic receptors.

B

Acetylcholine usually induces an excitatory postsynaptic potential when binding to ________ receptors and an inhibitory postsynaptic potential when binding to some ____________ receptors. A. NMDA, nicotinic B. nicotinic, muscarinic C. muscarinic, NMDA D. muscarinic, nicotinic

B

Cholinergic fibers use ____ as the neurotransmitter. A. norepinephrine B. acetylcholine C. dopamine D. serotonin

B

Conduction of an action potential in a myelinated axon is called A. point to point conduction. B. saltatory conduction. C. refractory conduction. D. cable conduction.

B

Endocannabinoids are retrograde neurotransmitters, meaning they are A. released from presynaptic neurons and diffuse to the postsynaptic neuron. B. released from postsynaptic neurons and diffuse to the presynaptic neuron. C. released from presynaptic neurons and diffuse back to the presynaptic cell body. D. None apply.

B

Excitatory postsynaptic potentials are produced by A. glycine. B. glutamic acid. C. gamma-aminobutyric acid. D. benzodiazepines.

B

Spatial summation A. occurs when a single neuron releases neurotransmitter rapidly. B. occurs because of the convergence of many neurons on a single postsynaptic cell. C. only involves excitatory postsynaptic potentials. D. only involves inhibitory postsynaptic potentials.

B

Synaptic plasticity involves structural changes in neurons such as A. formation of axillary branches B. formation of dendritic spines C. formation of more axon terminals D. mitosis of neurons

B

The __________ dopamine system may be involved in emotional reward and drug addiction. A. nigrostriatal B. mesolimbic C. amygdala D. dentate

B

The gap of exposed axon in the myelin sheath is the A. neurilemma. B. node of Ranvier. C. sheath of Schwann. D. white matter.

B

The mechanism that allows many Na+ ions to move into the axon is A. negative feedback. B. positive feedback. C. equilibrium feedback. D. None of the choices are correct.

B

The minimum depolarization needed to open Na+ gates is called the A. repolarization. B. threshold. C. refractory period. D. All-or-none law.

B

The myelin sheaths of CNS neurons are produced by A. Schwann cells. B. oligodendrocytes. C. ependymal cells. D. leukocytes.

B

The normal effect of β-endorphin can be blocked by A. curare. B. naloxone. C. muscarine. D. nicotine

B

What amino acid are dopamine, norepinephrine, and epinephrine derived from? A. histidine B. tyrosine C. tryptophan D. serine

B

What do muscarine and nicotine have in common? A. They are both antagonists for their respective receptors. B. They are both agonists for their respective receptors. C. They both activate-protein coupled channels. D. They have nothing in common.

B

What process occurs when glutamate-releasing presynaptic neurons stimulate postsynaptic release of endocannabinoids that acts as retrograde neurotransmitters? A. long-term potentiation B. long-term depression C. depolarization-induced suppression of inhibition D. All apply.

B

Which of the following is NOT a type of glutamate receptor? A. NMDA receptor B. muscarinic receptor C. kainate receptor D. All of the choices are correct.

B

Action potentials would be conducted most rapidly by A. a 10 mm diameter myelinated axon. B. a 10 mm diameter unmyelinated axon. C. a 40 mm diameter myelinated axon. D. a 40 mm diameter unmyelinated axon.

C

As the intensity of a stimulus increases, more axons will become activated. This process is called A. threshold. B. refraction. C. recruitment. D. None apply.

C

At what region of the neuron are action potentials first produced? A. dendrites B. cell body C. initial segment of an axon D. axon hillock

C

Blocking ____________ channels would prevent neuron depolarization. A. K+ B. Cl- C. Na+ D. Mg2+

C

Both long-term potentiation and long-term depression requires release of ___ from the postsynaptic neuron membrane. A. Cl- B. K+ C. Ca2+ D. Mg2+

C

Cells supporting neuron cell bodies in ganglia are termed A. astrocytes. B. ependymal cells. C. satellite cells. D. Schwann cells.

C

Chemicals that stimulate action potentials in postsynaptic cells are called A. hormones. B. enzymes. C. neurotransmitters. D. neurotrophins

C

During an action potential A. Na+ efflux causes depolarization. B. K+ influx causes repolarization. C. Na+ influx causes depolarization. D. K+ influx causes after-hyperpolarization.

C

Fetal neuron growth requires the actions of a group of chemicals known as A. endorphins. B. synapsins. C. neurotrophins. D. glutamates.

C

In a myelinated axon, Na+ channels are A. along the whole length of the axon. B. every 5 mm. C. concentrated at the nodes of Ranvier. D. less numerous at the nodes of Ranvier.

C

Local anesthetics block conduction of action potentials in sensory neurons by A. inhibiting the release of acetylcholine. B. binding to potassium channels. C. binding to sodium channels. D. binding to calcium channels.

C

Mutation of the N-methyl-D-aspartate (NMDA) receptor would affect the ability of ____________ to regulate neural function. A. acetylcholine B. epinephrine C. glutamate D. nitric oxide

C

Neuroleptics, which are used to treat schizophrenia, are A. dopamine agonists. B. ACh antagonists. C. dopamine antagonists. D. glutamate agonists.

C

Neurotransmitters A. are released by endocytosis. B. all bind to the same receptor. C. usually regulate ion channels. D. are actively transported across the synaptic cleft.

C

Serotonin is synthesized from the amino acid A. alanine. B. glycine. C. tryptophan. D. serine.

C

The ability of a neuron to transmit charge through its cytoplasm is called cable properties and is very A. good. B. strong. C. poor. D. easy.

C

The blood-brain barrier results mostly from the action of __________, a type of glial cell. A. ependymal cells B. microglia C. astrocytes D. oligodendrocytes

C

The disease ______________ is characterized by destruction of CNS myelin sheaths and the formation of hardened scars. A. Parkinson's B. Alzheimer's C. multiple sclerosis. D. myasthenia gravis

C

The membrane of resting nerve cells is more permeable to ____________ ions than ____________ ions. A. sodium, potassium B. calcium, potassium C. potassium, sodium D. chloride, potassium

C

The varied strength of synaptic transmission is called A. spatial summation. B. temporal summation. C. synaptic plasticity. D. EPSP.

C

What coding system do neurons use to get a greater response? A. greater amplitude of stimuli B. greater Na+ concentration gradient C. increased frequency of stimuli D. more active Na+/K+ pump

C

Which of the following is NOT true of histamine? A. it is derived from the amino acid histidine B. acts as a hormone that stimulates gastric secretion C. acts as a neurotransmitter in the brain to cause drowsiness D. acts as a regulator in inflammation and allergies

C

Which of the following is NOT true of nicotinic-gated channels? A. The binding of ACh allows diffusion of Na+ into and K+ out of the neuron. B. Only EPSPs are generated. C. Only action potentials are generated. D. Summation can occur because of a graded response.

C

Which of the following is true of axons? A. contain receptive areas B. very thin and short C. originates at the axon hillock on the cell body D. transmits graded electrochemical impulses

C

Which type of cell lines the ventricles of the brain and help produce cerebrospinal fluid? A. microglia B. satellite cells C. ependymal cells D. oligodendrocytes

C

ATP and adenosine can act as neurtransmitters A. by being released from astrocytes. B. as cotransmitters. C. as paracrine regulators. D. All apply.

D

Acetylcholine A. is always an excitatory neurotransmitter. B. can bind to adrenergic receptors. C. is an inhibitory neurotransmitter released by motor neurons. D. can bind to nicotinic receptors.

D

Action potential transmission in the PNS is decreased if which cells are damaged? A. astrocytes B. microglia C. oligodendrocytes D. Schwann cells

D

Axonal regeneration is inhibited by A. brain-derived neurotrophic factor. B. nerve growth factor. C. neurotrophin-3. D. myelin-associated inhibitory protein.

D

Catecholamines activate postsynaptic cells by A. inhibition of adenylate cyclase. B. increased Ca2+ influx into the target cell. C. inhibition of calmodulin. D. increased production of cyclic AMP.

D

Curare is a competitive ACh antagonist at _____________ ACh receptors. A. muscarinic B. NMDA C. kainate D. nicotinic

D

Degeneration of spinal motor neurons in adults may be due to a lack of ____________ factor. A. brain-derived neurotrophic (BDNF) B. neurotrophin-3 C. nerve growth (NGF) D. glial-derived neurotrophic (GDNF)

D

Endogenous cannabinoids have effects similar to the active ingredient in A. cocaine. B. nicotine. C. amphetamines. D. marijuana.

D

Hyperpolarization in the postsynaptic cell is caused by A. excitatory postsynaptic potentials. B. inhibitory postsynaptic potentials. C. movement of K+ out of the cell. D. Inhibitory postsynaptic potentials and movement of K+ out of the cell are correct.

D

If the binding of muscarine to its receptor in the heart causes the beta-gamma complex of the Gprotein to bind to a K+ channel, A. the K+ channel will close, leading to depolarization. B. the K+ channel will open, leading to depolarization. C. the K+ channel will close, leading to hyperpolarization and inhibition. D. the K+ channel will open, leading to hyperpolarization and inhibition.

D

Inhibition of neuropeptide Y synthesis would A. induce euphoria. B. induce obesity. C. stimulate leptin secretion. D. inhibit eating.

D

Retrograde transport A. moves toward the cell body. B. moves membranes, vesicles, and viruses. C. uses molecular motor proteins of dynein. D. All apply.

D

Synaptic vesicles are docked to the plasma membrane of the axon terminal by a protein complex called A. boutons. B. connexins. C. synaptotagmins. D. SNARE.

D

The binding of a neurotransmitter to its receptor protein causes ion channels to open in the postsynaptic membrane. What type of gates are these? A. chemically-regulated gates B. voltage-regulated gates C. ligand-regulated gates D. Chemically-regulated gates and ligand-regulated gates are correct.

D

The capacity of synapses for alteration at the molecular level is termed as A. synaptic modulation. B. synaptic alteration. C. synaptic capacitance. D. synaptic plasticity.

D

The most common neurotransmitter in the brain is A. glycine. B. acetylcholine. C. serotonin. D. GABA.

D

The period of time when Na+ channels are recovering from their inactive state and K+ channels are still open is the A. repolarization. B. absolute refractory period. C. relative refractory period. D. Repolarization and relative refractory period are correct.

D

What action produces an IPSP on the postsynaptic membrane? A. influx of Na+ ions B. opening of Ca2+ channels into the neuron C. outflow of K+ ions D. opening of Cl- channels into the neuron

D

What causes presynaptic inhibition? A. inactivation of Ca2+ channels B. a second neuron causes a reduction in neurotransmitter release from another neuron C. axoaxonic synapses D. All apply.

D

What is NOT true of conduction through dendrites and cell bodies of neurons? A. they are EPSPs B. they are spread by cable properties C. they can summate to reach threshold D. they are action potentials

D

What type of neuron is found entirely in the CNS? A. sensory neuron B. interneuron C. association neuron D. Interneuron and association neuron are correct.

D

What type of proteins are present at chemical synapses to ensure the close proximity of the presynaptic and postsynaptic membranes? A. connexins B. myelin C. terminal boutons D. cell adhesion molecules (CAMs)

D

Which gas(es) can function as a neurotransmitter? A. carbon dioxide B. nitric oxide C. carbon monoxide D. nitric oxide and carbon monoxide.

D

Which of the following are natural analgesics? A. endorphins B. enkephalins C. dynorphins D. All apply.

D

Which of the following effect(s) acetylcholine synaptic transmission? A. curare B. botulinum toxin C. strychnine D. curare and botulinum toxin.

D

Which of the following is NOT a function of astrocytes? A. can take up NT from a synapse B. can stimulate or inhibit neurons C. needed to form synapses in the CNS D. phagocytose foreign material in the CNS E. form the blood-brain barrier

D

Which of the following is NOT a function of neurotrophins? A. maintaining sympathetic ganglion B. sustaining neurons that use the NT dopamine C. embryonic development of neurons D. regeneration of injured motor neurons

D

Which of the following is NOT true of norepinephrine? A. released in both the CNS and PNS B. released by sympathetic neurons to smooth muscle, cardiac muscle, and glands C. amphetamines stimulate norepinephrine pathways D. causes depression in the CNS

D