CH 12 TEST BANKS

4) The ________ nervous system provides involuntary regulation of smooth muscle, cardiac muscle, and glandular activity. A) somatic B) peripheral C) autonomic D) afferent E) motor

C) autonomic

32) At a(n) ________ synapse, a neurotransmitter is released to stimulate the postsynaptic membrane. A) electrical B) cell C) chemical D) osmotic E) gap

C) chemical

30) The presence of ________ dramatically increases the speed at which an action potential moves along an axon. A) a capsule B) plasma protein C) neurilemma D) glial cells E) myelin

E) myelin

15) The site of intercellular communication between a neuron and another cell is the A) telodendria. B) synaptic terminals. C) collateral. D) hillock. E) synapse.

E) synapse.

88) Which of the following is true about threshold for an action potential? A) It is more positive than the resting potential. B) Voltage-gated potassium channels begin to close. C) Voltage-gated potassium channels begin to open. D) The membrane begins to hyperpolarize. E) Threshold for a typical neuron is approximately -30 mV.

A) It is more positive than the resting potential.

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

A) chemical

112) When cholinergic receptors are stimulated, A) sodium ions enter the postsynaptic neuron. B) sodium ions leave the postsynaptic neuron. C) chloride ions enter the postsynaptic neuron. D) chloride ions leave the postsynaptic neuron. E) norepinephrine deactivates acetylcholine.

A) sodium ions enter the postsynaptic neuron.

13) Axons terminate in a series of fine extensions known as A) telodendria. B) terminals. C) collaterals. D) dendrites. E) synapses.

A) telodendria

5) ________ carry motor information to peripheral effectors. A) Motor neurons B) Efferent neurons C) Multipolar neurons D) Afferent neurons E) Interneurons

B) Efferent neurons

25) A shift of the resting transmembrane potential toward 0 mV is called A) potential difference. B) depolarization. C) hyperpolarization. D) polarization. E) repolarization.

B) depolarization.

54) Damage to ependymal cells would most likely affect the A) formation of myelin sheaths. B) formation of cerebrospinal fluid. C) formation of ganglia. D) repair of axons. E) transport of neurotransmitters within axons.

B) formation of cerebrospinal fluid.

41) Which of the following is a type of glial cell found in the peripheral nervous system? A) astrocytes B) satellite cells C) oligodendrocytes D) microglia

B) satellite cells

51) Glial cells that surround the neurons in ganglia are A) astrocytes. B) satellite cells. C) oligodendrocytes. D) microglia. E) ependymal cells.

B) satellite cells.

113) If the axon terminal of a motor neuron suddenly became permeable to calcium ion, A) the neuron will fire an action potential. B) the motor end plate will be depolarized. C) the motor end plate will be hyperpolarized. D) neurotransmitter release will be blocked. E) the neuron will become unable to stimulate the muscle cell.

B) the motor end plate will be depolarized

97) Which point of the graph shows when potassium ion outflow exceeds sodium ion inflow? A) 1 B) 2 C) 3 D) 4

C) 3

70) Which of the following is not involved in creating the resting potential of a neuron? A) diffusion of potassium ions out of the cell B) diffusion of sodium ions into the cell C) membrane permeability for sodium ions greater than potassium ions D) membrane permeability for potassium ions greater than sodium ions E) The interior of the plasma membrane has an excess of negative charges.

C) membrane permeability for sodium ions greater than potassium ions

47) The myelin sheath that covers many CNS axons is formed by A) astrocytes. B) satellite cells. C) oligodendrocytes. D) microglia. E) ependymal cells.

C) oligodendrocytes.

59) At the normal resting potential of a typical neuron, its sodium-potassium exchange pump transports A) 1 intracellular sodium ion for 2 extracellular potassium ions. B) 2 intracellular sodium ions for 1 extracellular potassium ion. C) 3 intracellular sodium ions for 1 extracellular potassium ion. D) 3 intracellular sodium ions for 2 extracellular potassium ions. E) 3 extracellular sodium ions for 2 intracellular potassium ions.

D) 3 intracellular sodium ions for 2 extracellular potassium ions.

9) ________ carry sensory information to the CNS. A) Motor neurons B) Efferent neurons C) Multipolar neurons D) Afferent neurons E) Interneurons

D) Afferent neurons

77) If acetylcholine (ACh) causes inhibition of a postsynaptic neuron, to what type of membrane channel did the ACh bind? A) mechanically-regulated channel B) voltage-regulated sodium channel C) voltage-regulated calcium channel D) chemically-regulated potassium channel E) chemically-regulated sodium channel

D) chemically-regulated potassium channel

111) The effect that a neurotransmitter has on the postsynaptic membrane depends on the A) frequency of neurotransmitter release. B) nature of the neurotransmitter. C) characteristics of the receptors. D) quantity of neurotransmitters released. E) All of the answers are correct.

E) All of the answers are correct.

48) ________ line the brain ventricles and spinal canal. A) Astrocytes B) Satellite cells C) Oligodendrocytes D) Microglia E) Ependymal cells

E) Ependymal cells

86) How would a chemical that prevents the opening of voltage-regulated Na+ channels affect the function of a neuron? A) The neuron will only be able to hyperpolarize. B) The neuron will depolarize more rapidly. C) Action potentials will lack a repolarization phase. D) The neuron will automatically and repeatedly produce graded potentials. E) The neuron will only be capable of producing graded potentials.

E) The neuron will only be capable of producing graded potentials.

118) Which of the following is not a possible drug effect on synaptic function? A) interfere with neurotransmitter synthesis B) interfere with neurotransmitter reuptake C) prevent neurotransmitter inactivation D) block neurotransmitter binding to receptors E) change the type of receptor found in the postsynaptic membrane

E) change the type of receptor found in the postsynaptic membrane

3) The ________ division of the nervous system carries motor commands to muscles and glands. A) spinal B) peripheral C) autonomic D) afferent E) efferent

E) efferent

18) Neuron cell bodies in the PNS are clustered together in masses called A) fibers. B) tracts. C) nerves. D) nuclei. E) ganglia.

E) ganglia.

69) If the permeability of a resting axon to sodium ion increases, A) the membrane potential will repolarize. B) the membrane potential will hyperpolarize. C) inward movement of sodium ion will increase. D) outward movement of sodium ion will decrease. E) inward movement of sodium will increase and the membrane will depolarize.

E) inward movement of sodium will increase and the membrane will depolarize.

53) Extensive damage to oligodendrocytes in the CNS could result in A) loss of the structural framework of the brain. B) a breakdown of the blood-brain barrier. C) inability to produce scar tissue at the site of an injury. D) decreased production of cerebrospinal fluid. E) loss of sensation and motor control.

E) loss of sensation and motor control.