CH-37-38 Neurons, Synapses, and Signaling – Campbell Biology in Focus : Exam Guide

This Document Contains Chapters 37 to 38 Chapter 37: Neurons, Synapses, and Signaling 37.1 Multiple-Choice Questions 1) A simple nervous system A) must include chemical senses, mechanoreception, and vision. B) includes a minimum of 12 effector neurons. C) has information flow in only one direction: toward an integrating center. D) has information flow in only one direction: away from an integrating center. E) includes sensory information, an integrating center, and effectors. Answer: E 2) Most of the neurons in the human brain are A) sensory neurons. B) motor neurons. C) interneurons. D) auditory neurons. E) peripheral neurons. Answer: C 3) The nucleus and most of the organelles in a neuron are located in the A) dendritic region. B) axon hillock. C) axon. D) cell body. E) axon terminals. Answer: D 4) The point of connection between two communicating neurons is called the A) axon hillock. B) dendrite. C) synapse. D) cell body. E) glia. Answer: C 5) In a simple synapse, neurotransmitter chemicals are released by A) the dendritic membrane. B) the presynaptic membrane. C) axon hillocks. D) cell bodies. E) ducts on the smooth endoplasmic reticulum. Answer: B 6) Although the membrane of a "resting" neuron is highly permeable to potassium ions, its membrane potential does not exactly match the equilibrium potential for potassium because the neuronal membrane is also A) fully permeable to sodium ions. B) slightly permeable to sodium ions. C) fully permeable to calcium ions. D) impermeable to sodium ions. E) highly permeable to chloride ions. Answer: B 7) The operation of the sodium-potassium "pump" moves A) sodium and potassium ions into the cell. B) sodium and potassium ions out of the cell. C) sodium ions into the cell and potassium ions out of the cell. D) sodium ions out of the cell and potassium ions into the cell. E) sodium and potassium ions into the mitochondria. Answer: D 8) A cation that is more abundant as a solute in the cytosol of a neuron than it is in the interstitial fluid outside the neuron is A) HCO3-. B) Cl-. C) Ca++. D) Na+. E) K+. Answer: E 9) The membrane potential that exactly offsets an ion's concentration gradient is called the A) graded potential. B) threshold potential. C) equilibrium potential. D) action potential. E) inhibitory postsynaptic potential. Answer: C 10) ATP hydrolysis directly powers the movement of A) K+ out of cells. B) Na+ out of cells. C) Na+ into cells. D) Ca++ into cells. E) Cl— into cells. Answer: B 11) Two fundamental concepts about the ion channels of a "resting" neuron are that the channels A) are always open, but the concentration gradients of ions frequently change. B) are always closed, but ions move closer to the channels during excitation. C) open and close depending on stimuli, and are specific as to which ion can traverse them. D) open and close depending on chemical messengers, and are nonspecific as to which ion can traverse them. E) open in response to stimuli, and then close simultaneously, in unison. Answer: C 12) Opening all of the sodium channels, with all other ion channels closed—which is an admittedly artificial setting—on an otherwise typical neuron should move its membrane potential to A) -90 mV. B) -70 mV. C) 0 mV. D) +30 mV. E) +62 mV. Answer: E 13) The "selectivity" of a particular ion channel refers to its A) permitting passage by positive but not negative ions. B) permitting passage by negative but not positive ions. C) ability to change its size depending on the ion needing transport. D) binding with only one type of neurotransmitter. E) permitting passage only to a specific ion. Answer: E 14) For a neuron with an initial membrane potential at -70 mV, an increase in the movement of potassium ions out of that neuron's cytoplasm would result in the A) depolarization of the neuron. B) hyperpolarization of the neuron. C) replacement of potassium ions with sodium ions. D) replacement of potassium ions with calcium ions. E) neuron switching on its sodium-potassium pump to restore the initial conditions. Answer: B 15) A graded hyperpolarization of a membrane can be induced by A) increasing its membrane's permeability to Na+. B) decreasing its membrane's permeability to H+. C) decreasing its membrane's permeability to Cl-. D) increasing its membrane's permeability to Ca++. E) increasing its membrane's permeability to K+. Answer: E 16) Self-propagation and refractory periods are typical of A) action potentials. B) graded hyperpolarizations. C) excitatory postsynaptic potentials. D) threshold potentials. E) resting potentials. Answer: A 17) The "threshold" potential of a membrane is the A) point of separation from a living to a dead neuron. B) lowest frequency of action potentials a neuron can produce. C) minimum hyperpolarization needed to prevent the occurrence of action potentials. D) minimum depolarization needed to operate the voltage-gated sodium and potassium channels. E) peak amount of depolarization seen in an action potential. Answer: D 18) Action potentials move along axons A) more slowly in axons of large diameter as compared to those of small diameter. B) by the direct action of acetylcholine on the axonal membrane. C) by activating the sodium-potassium "pump" at each point along the axonal membrane. D) more rapidly in myelinated than in nonmyelinated axons. E) by reversing the concentration gradients for sodium and potassium ions. Answer: D 19) A toxin that binds specifically to voltage-gated sodium channels in axons would be expected to A) prevent the hyperpolarization phase of the action potential. B) prevent the depolarization phase of the action potential. C) prevent graded potentials. D) increase the release of neurotransmitter molecules. E) have most of its effects on the dendritic region of a neuron. Answer: B 20) After the depolarization phase of an action potential, the resting potential is restored by A) the opening of sodium activation gates. B) the opening of voltage-gated potassium channels and the closing of sodium channels. C) a decrease in the membrane's permeability to potassium and chloride ions. D) a brief inhibition of the sodium-potassium pump. E) the opening of more voltage-gated sodium channels. Answer: B 21) The "undershoot" phase of after-hyperpolarization is due to A) slow opening of voltage-gated sodium channels. B) sustained opening of voltage-gated potassium channels. C) rapid opening of voltage-gated calcium channels. D) slow restorative actions of the sodium-potassium ATPase. E) ions that move away from their open ion channels. Answer: B 22) Immediately after an action potential passes along an axon, it is not possible to generate a second action potential; thus, we state that the membrane is briefly A) hyperexcitable. B) refractory. C) fully depolarized. D) above threshold. E) at the equilibrium potential. Answer: B 23) An action potential can start in the middle of an axon and proceed in both opposite directions when A) the neuron is an inhibitory neuron and operating normally. B) only the middle section of the axon has been artificially stimulated by an electrode. C) the dendritic region fires an action potential. D) it is in its typical refractory state. E) its membrane potential is above the threshold. Answer: B 24) The fastest possible conduction velocity of action potentials is observed in A) thin, nonmyelinated neurons. B) thin, myelinated neurons. C) thick, nonmyelinated neurons. D) thick, myelinated neurons. Answer: D 25) In the sequence of permeability changes for a complete action potential, the first of these events that occurs is the A) activation of the sodium-potassium "pump." B) inhibition of the sodium-potassium "pump." C) opening of voltage-gated sodium channels. D) closing of voltage-gated potassium channels. E) opening of voltage-gated potassium channels. Answer: C 26) Saltatory conduction is a term applied to A) conduction of impulses across electrical synapses. B) an action potential that skips the axon hillock in moving from the dendritic region to the axon terminal. C) the rapid movement of an action potential reverberating back and forth along a neuron. D) jumping from one neuron to an adjacent neuron. E) jumping from one node of Ranvier to the next in a myelinated neuron. Answer: E 27) Two fundamental principles that characterize gated ion channels in the neuronal membrane are that the channels A) are always open, but the concentration gradients of ions frequently change. B) are always closed, but ions move closer to the channels during excitation. C) open and close depending on stimuli and are specific as to which ion can traverse them. D) open and close depending on chemical messengers and are nonspecific as to which ion can traverse them. E) open in response to stimuli, and then close simultaneously, in unison. Answer: C 28) The somatic nervous system can alter the activities of its targets, the skeletal muscle fibers, because A) it is electrically coupled by gap junctions to the muscles. B) its signals bind to receptor proteins on the muscles. C) its signals reach the muscles via the blood. D) its light pulses activate contraction in the muscles. E) it is connected to the internal neural network of the muscles. Answer: B 29) In a simple synapse, neurotransmitter chemicals are received by A) the dendritic membrane. B) the presynaptic membrane. C) axon hillocks. D) cell bodies. E) ducts on the smooth endoplasmic reticulum. Answer: A 30) The surface on a neuron that discharges the contents of synaptic vesicles is the A) dendrite. B) axon hillock. C) node of Ranvier. D) postsynaptic membrane. E) presynaptic membrane. Answer: E 31) Neurotransmitters are released from axon terminals via A) osmosis. B) active transport. C) diffusion. D) transcytosis. E) exocytosis. Answer: E 32) Neural transmission across a mammalian synapse is accomplished by A) the movement of sodium and potassium ions from the presynaptic neuron into the postsynaptic neuron. B) impulses traveling as electrical currents across the synapse. C) impulses causing the release of a chemical signal and its diffusion across the synapse. D) impulses ricocheting back and forth across the synapse. E) the movement of calcium ions from the presynaptic into the postsynaptic neuron. Answer: C 33) The release of acetylcholine from the terminal of a motor neuron is most directly linked to the A) entry of potassium into the axon terminal. B) exit of potassium from the axon terminal. C) entry of sodium into the axon terminal. D) exit of sodium from the axon terminal. E) entry of calcium into the axon terminal. Answer: E 34) The observation that the acetylcholine released into the junction between a motor neuron and a skeletal muscle binds to a sodium channel and opens it is an example of a A) voltage-gated sodium channel. B) voltage-gated potassium channel. C) ligand-gated sodium channel. D) second-messenger-gated sodium channel. E) chemical that inhibits action potentials. Answer: C 35) An inhibitory postsynaptic potential (IPSP) occurs in a membrane made more permeable to A) potassium ions. B) sodium ions. C) calcium ions. D) ATP. E) all neurotransmitter molecules. Answer: A 36) The following steps refer to various stages in transmission at a chemical synapse. 1. Neurotransmitter binds with receptors associated with the postsynaptic membrane. 2. Calcium ions rush into the neuron's cytoplasm. 3. An action potential depolarizes the membrane of the axon terminal. 4. The ligand-gated ion channels open. 5. The synaptic vesicles release neurotransmitter into the synaptic cleft. Which sequence of events is correct? A) 1 → 2 → 3 → 4 → 5 B) 2 → 3 → 5 → 4 → 1 C) 3 → 2 → 5 → 1 → 4 D) 4 → 3 → 1 → 2 → 5 E) 5 → 1 → 2 → 4 → 3 Answer: C 37) The activity of acetylcholine in a synapse is terminated by its A) active transport across the presynaptic membrane. B) diffusion across the presynaptic membrane. C) active transport across the postsynaptic membrane. D) diffusion across the postsynaptic membrane. E) degradation by a hydrolytic enzyme on the postsynaptic membrane. Answer: E 38) Ionotropic receptors are found at synapses operated via A) ligand-gated ion channels. B) second-messenger-gated ion channels. C) electrical synapses. D) inhibitory, but not excitatory, synapses. E) excitatory, but not inhibitory, synapses. Answer: A 39) An example of ligand-gated ion channels is A) the spreading of action potentials in the heart. B) acetylcholine receptors at the neuromuscular junction. C) cAMP-dependent protein kinases. D) action potentials on the axon. E) graded hyperpolarization. Answer: B 40) Neurotransmitters categorized as inhibitory are expected to A) act independently of their receptor proteins. B) close potassium channels. C) open sodium channels. D) close chloride channels. E) hyperpolarize the membrane. Answer: E 41) When several EPSPs arrive at the axon hillock from different dendritic locations, depolarizing the postsynaptic cell to threshold for an action potential, this is an example of A) temporal summation. B) spatial summation. C) tetanus. D) the refractory state. E) an action potential with an abnormally high peak of depolarization. Answer: B 42) When several IPSPs arrive at the axon hillock rapidly in sequence from a single dendritic location, hyperpolarizing the postsynaptic cell more and more and thus preventing an action potential, this is an example of A) temporal summation. B) spatial summation. C) tetanus. D) the refractory state. E) an action potential with an abnormally high peak of depolarization. Answer: A 43) Assume that a single IPSP has a negative magnitude of —0.5 mV at the axon hillock, and that a single EPSP has a positive magnitude of +0.5 mV. For a neuron with an initial membrane potential of —70 mV, the net effect of the simultaneous arrival of six IPSPs and two EPSPs would be to move the membrane potential to A) -72 mV. B) -71 mV. C) -70 mV. D) -69 mV. E) -68 mV. Answer: A 44) Receptors for neurotransmitters are of primary functional importance in assuring one-way synaptic transmission because they are mostly found on the A) axonal membrane. B) axon hillock. C) dendritic membrane. D) mitochondrial membrane. E) presynaptic membrane. Answer: C 45) Functionally, which cellular location is the neuron's "decision-making site" as to whether or not an action potential will be initiated? A) axonal membranes B) axon hillocks C) dendritic membranes D) mitochondrial membranes E) presynaptic membranes Answer: B 46) Neurotransmitters affect postsynaptic cells by A) initiating signal transduction pathways in the cells. B) causing molecular changes in the cells. C) affecting ion-channel proteins. D) altering the permeability of the cells. E) All of these options are correct. Answer: E 47) The major inhibitory neurotransmitter of the human brain is A) acetylcholine. B) epinephrine. C) glutamate. D) nitric oxide. E) GABA. Answer: E 48) A neuropeptide that might function as a natural analgesic is A) acetylcholine. B) epinephrine. C) endorphin. D) nitric oxide. E) GABA. Answer: C 49) An amino acid that operates at inhibitory synapses in the brain is A) acetylcholine. B) epinephrine. C) endorphin. D) nitric oxide. E) GABA. Answer: E 50) The botulinum toxin reduces the synaptic release of A) acetylcholine. B) epinephrine. C) endorphin. D) nitric oxide. E) GABA. Answer: A 51) The heart rate decreases in response to the arrival of A) acetylcholine. B) epinephrine. C) endorphin. D) nitric oxide. E) GABA. Answer: A 52) A chemical that affects neuronal function but is not stored in presynaptic vesicles is A) acetylcholine. B) epinephrine. C) endorphin. D) nitric oxide. E) GABA. Answer: D 53) Motor neurons alter skeletal muscle activities by releasing neurotransmitter because A) they are electrically coupled by gap junctions to the muscles. B) their signals bind to receptor proteins on the muscles. C) their signals reach the muscles via the blood. D) their light pulses activate contraction in the muscles. E) they are connected to the internal neural network of the muscles. Answer: B 54) Most of the synapses in vertebrates conduct information in only one direction A) as a result of the nodes of Ranvier. B) as a result of voltage-gated sodium channels found only in the vertebrate system. C) because vertebrate nerve cells have dendrites. D) because only the postsynaptic cells can bind and respond to neurotransmitters. E) because the sodium-potassium pump moves ions in one direction. Answer: D 37.2 Art Questions For the following questions, refer to the graph of an action potential in Figure 37.1. Figure 37.1 1) The membrane potential is closest to the equilibrium potential for potassium at label A) A. B) B. C) C. D) D. E) E. Answer: D 2) The period in which voltage-gated potassium channels are open and hyperpolarization has yet to occur is at label A) A. B) B. C) C. D) D. E) E. Answer: C 3) The membrane’s permeability to sodium ions is at its maximum at label A) A. B) B. C) C. D) D. E) E. Answer: B 4) The minimum graded depolarization needed to operate the voltage-gated sodium and potassium channels is indicated by the label A) A. B) B. C) C. D) D. E) E. Answer: A 5) The cell is not hyperpolarized; however, repolarization is in progress, as the sodium channels are closing or closed, and many potassium channels have opened, at label A) A. B) B. C) C. D) D. E) E. Answer: C 6) The neuronal membrane is at its resting potential at label A) A. B) B. C) C. D) D. E) E. Answer: E 7) Action potentials are normally carried in only one direction: from the axon hillock toward the axon terminals. If you experimentally depolarize the middle of the axon to threshold, using an electronic probe, then A) no action potential will be initiated. B) an action potential will be initiated and proceed only in the normal direction toward the axon terminal. C) an action potential will be initiated and proceed only back toward the axon hillock. D) two action potentials will be initiated, one going toward the axon terminal and one going back toward the hillock. E) an action potential will be initiated, but it will die out before it reaches the axon terminal. Answer: D 37.3 Scenario Question 1) Assume that excessive consumption of ethanol increases the influx of negative chloride ions into "commonsense" neurons whose action potentials are needed for you to act appropriately and not harm yourself or others. Thus, any resulting poor decisions associated with ethanol ingestion are likely due to A) increased membrane depolarization of "commonsense" neurons. B) increased membrane hyperpolarization of "commonsense" neurons. C) more action potentials in your "commonsense" neurons. D) more EPSPs in your "commonsense" neurons. E) fewer IPSPs in your "commonsense" neurons. Answer: B 37.4 End-of-Chapter Questions 1) What happens when a resting neuron’s membrane depolarizes? A) There is a net diffusion of Na+ out of the cell. B) The equilibrium potential for K+ (EK) becomes more positive. C) The neuron’s membrane voltage becomes more positive. D) The neuron is less likely to generate an action potential. E) The cell’s inside is more negative than the outside. Answer: C 2) A common feature of action potentials is that they A) cause the membrane to hyperpolarize and then depolarize. B) can undergo temporal and spatial summation. C) are triggered by a depolarization that reaches threshold. D) move at the same speed along all axons. E) require the diffusion of Na+ and K+ through ligand-gated channels to propagate. Answer: C 3) Where are neurotransmitter receptors located? A) the nuclear membrane B) the nodes of Ranvier C) the postsynaptic membrane D) synaptic vesicle membranes E) the myelin sheath Answer: C 4) Why are action potentials usually conducted in one direction? A) The nodes of Ranvier conduct potentials in one direction. B) The brief refractory period prevents reopening of voltage gated Na+ channels. C) The axon hillock has a higher membrane potential than the terminals of the axon. D) Ions can flow along the axon in only one direction. E) Voltage-gated channels for both Na+ and K+ open in only one direction. Answer: B 5) Which of the following is a direct result of depolarizing the presynaptic membrane of an axon terminal? A) Voltage-gated calcium channels in the membrane open. B) Synaptic vesicles fuse with the membrane. C) The postsynaptic cell produces an action potential. D) Ligand-gated channels open, allowing neurotransmitters to enter the synaptic cleft. E) An EPSP or IPSP is generated in the postsynaptic cell. Answer: A 6) Suppose a particular neurotransmitter causes an IPSP in postsynaptic cell X and an EPSP in postsynaptic cell Y. A likely explanation is that A) the threshold value in the postsynaptic membrane is different for cell X and cell Y. B) cell Y forms chemical synapses, whereas cell X forms electrical synapses. C) the axon of cell X is myelinated, but that of cell Y is not. D) only cell Y produces an enzyme that terminates the activity of the neurotransmitter. E) cells X and Y express different receptor molecules for this particular neurotransmitter. Answer: E Chapter 38: Nervous and Sensory Systems 38.1 Multiple-Choice Questions 1) The central nervous system is lacking in animals that have A) a complete gut. B) bilateral symmetry. C) radial symmetry. D) a closed circulatory system. E) excitable membranes. Answer: C 2) Cephalization, the clustering of neurons and interneurons in the anterior part of the animal, is apparent in A) Hydra. B) cnidarians. C) Planaria. D) sea stars. E) invertebrate animals with radial symmetry. Answer: C 3) Choose the correct match of glial cell type and function. A) astrocytes—metabolize neurotransmitters and modulate synaptic effectiveness B) oligodendrocytes—produce the myelin sheaths of myelinated neurons in the peripheral nervous system C) microglia—produce the myelin sheaths of myelinated neurons in the central nervous system D) radial glia—the source of immune protection against pathogens. E) Schwann cells—provide nutritional support to nonmyelinated neurons Answer: A 4) The cerebrospinal fluid is A) a filtrate of the blood. B) a secretion of glial cells. C) a secretion of interneurons. D) cytosol secreted from ependymal cells. E) secreted by the hypothalamus. Answer: A 5) The blood-brain barrier A) is formed by tight junctions. B) is formed by oligodendrocytes. C) tightly regulates the intracellular environment of the CNS. D) uses chemical signals to communicate with the spinal cord. E) provides support to the brain tissue. Answer: A 6) Myelinated neurons are especially abundant in A) the gray matter of the brain and the white matter of the spinal cord. B) the white matter of the brain and the gray matter of the spinal cord. C) the gray matter of the brain and the gray matter of the spinal cord. D) the white matter in the brain and the white matter in the spinal cord. E) all areas of the brain and spinal cord. Answer: D 7) Cerebrospinal fluid can be described as all of the following except A) functioning in transport of nutrients and hormones through the brain. B) a product of the filtration of blood in the brain. C) formed from layers of connective tissue. D) functioning to cushion the brain. E) filling cavities in the brain called ventricles. Answer: C 8) The divisions of the nervous system that have antagonistic, or opposing, actions are the A) motor and sensory systems. B) sympathetic and parasympathetic systems. C) presynaptic and postsynaptic membranes. D) forebrain and hindbrain. E) central nervous system and peripheral nervous system. Answer: B 9) Preparation for the fight-or-flight response includes activation of the ________ nervous system. A) sympathetic B) somatic C) central D) visceral E) parasympathetic Answer: A 10) Exercise and emergency reactions include A) increased activity in all parts of the peripheral nervous system. B) increased activity in the sympathetic division and decreased activity in the parasympathetic division. C) decreased activity in the sympathetic division and increased activity in the parasympathetic division. D) increased activity in the enteric nervous system. E) reduced heart rate and blood pressure. Answer: B 11) The activation of the parasympathetic branch of the autonomic nervous system is associated with A) resting and digesting. B) release of epinephrine into the blood. C) increased metabolic rate. D) fight-or-flight responses. E) intensive aerobic exercise. Answer: A 12) In a cephalized invertebrate, the system that transmits "efferent" impulses from the anterior ganglion to distal segments is the A) central nervous system. B) peripheral nervous system. C) autonomic nervous system. D) parasympathetic nervous system. E) sympathetic nervous system. Answer: B 13) Afferent neuronal systems include the A) sensory systems. B) peripheral nervous system. C) autonomic nervous system. D) parasympathetic nervous system. E) sympathetic nervous system. Answer: A 14) Imagine you are resting comfortably on a sofa after dinner. This could be described as a state with A) increased activity in the sympathetic, parasympathetic, and enteric nervous systems. B) decreased activity in the sympathetic, parasympathetic, and enteric nervous systems. C) decreased activity in the sympathetic nervous system, and increased activity in the parasympathetic and enteric nervous systems. D) increased activity in the sympathetic nervous system, and decreased activity in the parasympathetic and enteric nervous systems. E) increased activity in the sympathetic nervous system, decreased activity in the parasympathetic nervous system, and increased activity in the enteric nervous system. Answer: C 15) The system that modulates excitation and inhibition of the smooth and cardiac muscles of the digestive, cardiovascular, and excretory systems is the A) central nervous system. B) motor system. C) autonomic nervous system. D) parasympathetic nervous system. E) sympathetic nervous system. Answer: C 16) The 11 pairs of appendages projecting from the rostral area of star-nosed moles are A) chemosensory structures. B) tactile structures. C) olfactory structures. D) highly sensitive photoreceptors. E) gustatory structures. Answer: B 17) Central coordination of vertebrate biological rhythms in physiology and behavior resides in the A) pituitary gland. B) hypothalamus. C) cerebrum. D) cerebellum. E) thalamus. Answer: B 18) The endogenous nature of biological rhythms is based on the observation that animals isolated from light and dark cues A) continue to have cycles of exactly 24 hours in duration. B) continue to have cycles of approximately 24 hours in duration–some more rapid, some slower. C) synchronize activity with whatever lighting cycle is imposed on them. D) cease having any rhythms. E) are independent of any genetic determinants. Answer: B 19) The bottlenose dolphin breathes air but can sleep in the ocean because it A) ceases breathing while sleeping and remains underwater. B) sleeps for only 30 minutes at a time, the maximum interval for which it can cease breathing. C) fills its swim bladder with air to keep its blowhole above the surface of the water while it sleeps. D) moves to shallow water to sleep, so it does not need to swim to keep its blowhole above the surface of the water. E) alternates which half of its brain is asleep and which half is awake. Answer: E 20) The telencephalon region of the developing brain of a mammal A) develops as the neural tube differentiates. B) develops from the midbrain. C) is the brain region most like that of ancestral vertebrates. D) gives rise to the cerebrum. E) divides further into the metencephalon and myelencephalon. Answer: D 21) Increases and decreases of the heart rate result from changes in the activity of the A) corpus callosum. B) medulla oblongata. C) thalamus. D) pituitary. E) cerebellum. Answer: B 22) The unconscious control of respiration and circulation is associated with the A) thalamus. B) cerebellum. C) medulla oblongata. D) corpus callosum. E) cerebrum. Answer: C 23) Which of the following structures are correctly paired? A) forebrain and medulla oblongata B) forebrain and cerebellum C) midbrain and cerebrum D) hindbrain and cerebellum E) brainstem and anterior pituitary gland Answer: D 24) Hormones that are secreted by the posterior pituitary gland are made in the A) cerebrum. B) cerebellum. C) thalamus. D) hypothalamus. E) medulla oblongata. Answer: D 25) The coordination of groups of skeletal muscles is driven by activity in the A) cerebrum. B) cerebellum. C) thalamus. D) hypothalamus. E) medulla oblongata. Answer: B 26) The regulation of body temperature derives from the activity of the A) cerebrum. B) cerebellum. C) thalamus. D) hypothalamus. E) medulla oblongata. Answer: D 27) The regulatory centers for the respiratory and circulatory systems are found in the A) cerebrum. B) cerebellum. C) thalamus. D) hypothalamus. E) medulla oblongata. Answer: E 28) Food and water appetites are under the regulatory influence of the A) cerebrum. B) cerebellum. C) thalamus. D) hypothalamus. E) medulla oblongata. Answer: D 29) The suprachiasmatic nuclei are found in the A) thalamus. B) hypothalamus. C) epithalamus. D) amygdala. E) Broca's area. Answer: B 30) Calculation, contemplation, and cognition are human activities associated with increased activity in the A) pituitary gland. B) hypothalamus. C) cerebrum. D) cerebellum. E) spinal cord. Answer: C 31) An organism that lacks integration centers A) cannot receive stimuli. B) will not have a nervous system. C) will not be able to interpret stimuli. D) can be expected to lack myelinated neurons. Answer: C 32) The motor cortex is part of the A) cerebrum. B) cerebellum. C) spinal cord. D) midbrain. E) medulla oblongata. Answer: A 33) In mammals, advanced cognition is usually correlated with a large and very convoluted neocortex, but birds are capable of sophisticated cognition because they have A) a more advanced cerebellum. B) a cerebellum with several flat layers. C) a pallium with neurons clustered into nuclei. D) microvilli to increase the brain's surface area. Answer: C 34) Wernicke's and Broca's regions of the brain affect A) olfaction. B) vision. C) speech. D) memory. E) hearing. Answer: C 35) Which of the following shows a brain structure correctly paired with one of its primary functions? A) frontal lobe—decision making B) occipital lobe—control of skeletal muscles C) temporal lobe—visual processing D) cerebellum—language comprehension E) occipital lobe—speech production Answer: A 36) If you were writing an essay, the part of your brain that would be actively involved in this task is A) the temporal and frontal lobes. B) the parietal lobe. C) Broca's area. D) Wernicke's area. E) the occipital lobe. Answer: A 37) Our understanding of mental illness has been most advanced by discoveries involving the A) degree of convolutions in the brain's surface. B) evolution of the telencephalon. C) sequence of developmental specialization. D) chemicals involved in brain communications. E) nature of the blood-brain barrier. Answer: D 38) Wernicke's area A) is active when speech is heard and comprehended. B) is active during the generation of speech. C) coordinates the response to olfactory sensation. D) is active when you are reading silently. E) is found on the left side of the brain. Answer: A 39) Failure of an embryonic neuron to establish a synaptic connection to another cell A) converts that neuron to an ependymal cell. B) causes the neuron to migrate to another part of the brain. C) converts that neuron to a glial cell. D) leads to Alzheimer's disease. E) results in the apoptosis of that neuron. Answer: E 40) Short-term memory information processing usually causes changes in the A) brainstem. B) medulla. C) hypothalamus. D) hippocampus. E) cranial nerves. Answer: D 41) Forming new long-term memories is strikingly disrupted after damage to the A) thalamus. B) hypothalamus. C) hippocampus. D) somatosensory cortex. E) primary motor cortex. Answer: C 42) When Phineas Gage had a metal rod driven into his frontal lobe he experienced A) loss of the ability to reason. B) loss of all short-term memory. C) greatly altered emotional responses. D) loss of all long-term memory. E) loss of his sense of balance. Answer: C 43) An injury to the occipital lobe will likely impair the function of the A) primary visual cortex. B) thalamus. C) optic chiasma. D) sense of taste. E) sense of touch. Answer: A 44) A ligand for the umami receptor in the sense of taste is A) glucose. B) sodium ions. C) potassium ions. D) hydrogen ions. E) monosodium glutamate. Answer: E 45) The olfactory bulbs are located in the A) nasal cavity. B) anterior pituitary gland. C) posterior pituitary gland. D) brain. E) brainstem. Answer: D 46) The correct sequence of sensory processing is A) sensory adaptation → stimulus reception → sensory transduction → sensory perception. B) stimulus reception → sensory transduction → sensory perception → sensory adaptation. C) sensory perception → stimulus reception → sensory transduction → sensory adaptation. D) sensory perception → sensory transduction → stimulus reception → sensory adaptation. E) stimulus reception → sensory perception → sensory adaptation → sensory transduction. Answer: B 47) Artificial electrical stimulation of a human's capsaicin-sensitive neurons would likely produce the sensation of A) cold temperature. B) hot temperature. C) tactile stimulus. D) odor of pepper. E) deep pressure. Answer: B 48) Artificial electrical stimulation of a human's menthol-sensitive neurons would likely produce the sensation of A) cold temperature. B) hot temperature. C) tactile stimulus. D) odor of pepper. E) deep pressure. Answer: A 49) Tastes and smells are distinct kinds of environmental information in that A) neural projections from taste receptors reach different parts of the brain than the neural projections from olfactory receptors. B) the single area of the cerebral cortex that receives smell and taste signals can distinguish tastes and smells by the pattern of action potentials received. C) tastant molecules are airborne, whereas odorant molecules are dissolved in fluids. D) distinguishing tastant molecules requires learning, whereas smell discrimination is an innate process. E) odorants bind to receptor proteins, but none of the tastant stimuli will bind to receptors. Answer: A 50) Stimuli alter the activity of excitable sensory cells via A) integration. B) transmission. C) transduction. D) transcription. E) amplification. Answer: C 51) Choose the correct sequence of the following events leading to the sensory processing of a stimulus. 1. transmission 2. transduction 3. integration 4. amplification A) 1 → 2 → 3 → 4 B) 1 → 4 → 2 → 3 C) 2 → 4 → 1 → 3 D) 3 → 1 → 2 → 4 E) 3 → 1 → 4 → 2 Answer: C 52) Immediately after putting on a shirt, your skin might feel itchy. However, this perception soon fades due to A) sensory adaptation. B) accommodation. C) the increase of transduction. D) reduced motor unit recruitment. E) reduced receptor amplification. Answer: A 53) A given photon of light may trigger an action potential with thousands of times more energy because the signal strength is magnified by A) the receptor. B) a G protein. C) an enzyme-catalyzed reaction. D) sensory adaptation. E) triggering several receptors at once. Answer: C 54) The generation of action potentials in olfactory neurons initiated by odors drawn into the nasal cavity is an example of A) perception. B) sensory transduction. C) sensory adaptation. D) habituation. E) lateral inhibition. Answer: B 55) Umami perception would be stimulated by A) sugar water. B) chocolate milk. C) a savory and rich cheese. D) acidic orange juice. E) salt water. Answer: C 56) Proteins coded by a very large family of related genes are active in the sensory transduction of A) gustatory stimuli. B) olfactory stimuli. C) visual stimuli. D) auditory stimuli. E) stimuli related to the position of the head. Answer: B 57) Statocysts contain cells that are A) mechanoreceptors used to detect orientation relative to gravity. B) chemoreceptors used in selecting migration routes. C) photoreceptors used in setting biological rhythms. D) thermoreceptors used in prey detection. E) chemoreceptors used in acid-base balance. Answer: A 58) An earthworm without a statocyst would not be able to A) move. B) sense light. C) hear. D) orient with respect to gravity. E) respond to touch. Answer: D 59) The cellular membrane across which ion flow varies during auditory transduction is the A) tectorial membrane. B) tympanic membrane. C) round-window membrane. D) hair cell membrane. E) basilar membrane. Answer: D 60) Sound waves arriving at a listener first strike the A) tectorial membrane. B) tympanic membrane. C) round-window membrane. D) hair cell membrane. E) basilar membrane. Answer: B 61) The pathway leading to the perception of sound by mammals begins with the A) hair cells of the organ of Corti, which rests on the basilar membrane, coming in contact with the tectorial membrane. B) hair cells of the organ of Corti, which rests on the tympanic membrane, coming in contact with the tectorial membrane. C) hair cells of the organ of Corti, which rests on the tectorial membrane, coming in contact with the basilar membrane. D) hair cells of the organ of Corti coming in contact with the tectorial membrane as a result of fluid waves in the cochlea causing vibrations in the round window. E) hair cells on the tympanic membrane as a result of fluid waves in the cochlea causing vibrations in the round window. Answer: A 62) The cochlea is an organ of auditory transduction that contains A) fluid and cells that can undergo mechanosensory transduction. B) air and cells that produce wax. C) air and small bones that vibrate in response to sound waves. D) fluid with stacks of chemosensory cells. E) air and statocysts activated by movement. Answer: A 63) Dizziness is a perceived sensation that can occur when A) the hair cells in the cochlea move more than their normal limits. B) moving fluid in the semicircular canals encounters a stationary cupula. C) rods and cones provide information that does not correspond with information received by cochlear hair cells. D) the basilar membrane makes physical contact with the tectorial membrane. E) the utricle is horizontal but the saccule is vertical. Answer: B 64) The perceived pitch of a sound depends on A) which part of the tympanic membrane is being vibrated by sound waves. B) which part of the oval window produces waves in the cochlear fluid. C) which region of the basilar membrane was set in motion. D) whether or not the sound moves the incus, malleus, and stapes. E) the listener having had training in music. Answer: C 65) The sand grains or other dense materials resting on mechanoreceptors used by most invertebrates to sense gravity are called A) cochlea. B) statoliths. C) stapes. D) pinnae. E) antennae. Answer: B 66) It can be very difficult to select an angle for sneaking up to a grasshopper to catch it because grasshoppers have A) excellent hearing for detecting predators. B) compound eyes with multiple ommatidia. C) eyes with multiple fovea. D) a camera-like eye with multiple fovea. E) binocular vision. Answer: B 67) Sensory transduction of light/dark information in the vertebrate retina is accomplished by A) ganglion cells. B) amacrine cells. C) bipolar cells. D) horizontal cells. E) rods and cones. Answer: E 68) Rods exposed to light will A) depolarize due to the opening of sodium channels. B) hyperpolarize due to the closing of sodium channels. C) depolarize due to the opening of potassium channels. D) hyperpolarize due to the closing of potassium channels. E) fire one action potential for each photon received. Answer: B 69) A rod exposed to light will A) fire action potentials that will increase its release of glutamate. B) undergo a graded depolarization that will increase its release of glutamate. C) undergo a graded hyperpolarization that will increase its release of glutamate. D) undergo a graded depolarization that will decrease its release of glutamate. E) undergo a graded hyperpolarization that will decrease its release of glutamate. Answer: E 70) In the human retina A) cone cells can detect color, but rod cells cannot. B) cone cells are more sensitive than rod cells to light. C) cone cells, but not rod cells, have a visual pigment. D) rod cells are most highly concentrated in the center of the retina. E) rod cells require higher illumination for stimulation than do cone cells. Answer: A 38.2 Art Questions Refer to the illustration of the limbic system in Figure 38.1 to help answer the next few questions. Figure 38.1 1) In Figure 38.1, which letter points to the amygdala? A) A B) B C) C D) D E) E Answer: D 2) In Figure 38.1, which letter points to the thalamus? A) A B) B C) C D) D E) E Answer: A 3) In Figure 38.1, which letter points to the olfactory bulb? A) A B) B C) C D) D E) E Answer: C 4) In Figure 38.1, which letter points to the hippocampus? A) A B) B C) C D) D E) E Answer: E 5) In Figure 38.1, which letter points to the hypothalamus? A) A B) B C) C D) D E) E Answer: B Figure 38.2 6) The structure diagrammed in Figure 38.2 is the A) neuromast. B) statocyst. C) taste bud. D) ommatidium. E) olfactory bulb. Answer: B The next questions refer to the diagram of the ear in Figure 38.3. Figure 38.3 7) The structure involved in equalizing the pressure between the ear and the atmosphere is represented by number A) 7. B) 1. C) 8. D) 9. E) 10. Answer: C 8) The sense of head motion begins with sensory transduction by the structures at which numbers? A) 2, 3, and 4 B) 2, 5, and 7 C) 4 D) 5 E) 7 and 8 Answer: D 9) Vibrations of the tympanic membrane are transmitted to the oval window by the structures at which numbers? A) 1, 2, 3, and 4 B) 2, 3, and 4 C) 3 and 4 D) 4 E) 5 Answer: B 10) The organ of Corti is contained in the structure numbered A) 3. B) 4. C) 5. D) 6. E) 7. Answer: E 11) Hair cells are found in the structures represented by numbers A) 1 and 2. B) 3 and 4. C) 5 and 7. D) 6 and 8. E) 9 and 10. Answer: C 38.3 Scenario Question 1) Experiments with genetically altered mice showed that the mice would consume abnormally high amounts of bitter-tasting compounds in water after their A) hormone receptors for digestive hormones were reduced or eliminated, showing that bitter tastes are reinforced by digestive responses. B) salt-taste cells were altered to express receptors for bitter tastants, suggesting that animals have unregulated salt appetites. C) visual sense was reduced or eliminated, suggesting that mice learn visual cues about bitter tastes. D) olfactory sense was reduced or eliminated, suggesting that mice learn odor cues about bitter tastes. E) sweet-taste cells were altered to express receptors for bitter tastants, suggesting that the sensation of taste depends only on which taste cell is stimulated. Answer: E 38.4 End-of-Chapter Questions 1) Patients with damage to Wernicke’s area have difficulty A) coordinating limb movement. B) generating speech. C) recognizing faces. D) understanding language. E) experiencing emotion. Answer: D 2) The cerebral cortex does not play a major role in A) short-term memory. B) long-term memory. C) circadian rhythm. D) foot-tapping rhythm. E) breath holding. Answer: C 3) The middle ear converts A) air pressure waves to fluid pressure waves. B) fluid pressure waves to air pressure waves. C) air pressure waves to nerve impulses. D) fluid pressure waves to nerve impulses. E) pressure waves to hair cell movements. Answer: A 4) If the following events are arranged in the order in which they occur for an animal hiding in response to seeing a predator, which is the fourth event in the series? A) signaling by an afferent PNS neuron B) signaling by an efferent PNS neuron C) information processing in the CNS D) activation of a sensory receptor E) activation of a motor system Answer: B 5) Injury to just the hypothalamus would most likely disrupt A) short-term memory. B) coordination during locomotion. C) executive functions, such as decision making. D) sorting of sensory information. E) regulation of body temperature. Answer: E 6) Which sensory distinction is not encoded by a difference in which axon transfers the information to the brain? A) white and red B) red and green C) loud and faint D) salty and sweet E) spicy and cool Answer: C 7) Although some sharks close their eyes just before they bite, their bites are on target. Researchers have noted that sharks often misdirect their bites at metal objects and that they can find batteries buried under sand. This evidence suggests that sharks keep track of their prey during the split second before they bite in the same way that A) a rattlesnake finds a mouse in its burrow. B) an insect avoids being stepped on. C) a star-nosed mole locates its prey in tunnels. D) a platypus locates its prey in a muddy river. E) a flatworm avoids light places. Answer: D Test Bank for Campbell Biology in Focus Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Robert B. Jackson, Jane B. Reece 9780321813664, 9780321962751, 9780134710679