Univ. of Illinois, Urbana-Champaign Bio/Neuro 303 Chapter 9 - Study Questions *** LAST UPDATED 02 October 2002 *** 1. A sensory receptor cell can best be defined as a neuron that a. responds to something other than a synaptic transmitter substance. *b. is specialized for the transduction of energy, resulting in a change in membrane potential. c. receives no synapses from other neurons. d. responds only to one particular form of energy. 3. A proprioceptor is a sense organ that conveys information about a. interior body conditions, such as arterial blood pressure. *b. the relative movement of body parts. c. touch from the body surface. d. stimuli that originate from a distance (such as light). 5. A taste receptor is a(n) *a. chemoreceptor. b. electroreceptor. c. mechanoreceptor. d. photoreceptor. 6. A neuromast organ is a(n) a. chemoreceptor. b. electroreceptor. *c. mechanoreceptor. d. photoreceptor. 7. A muscle spindle sense organ is a a. chemoreceptor. b. electroreceptor. *c. mechanoreceptor. d. photoreceptor. 9. The retina of the human eye is not sensitive to ultraviolet light. This is an example of a. sense organ reafference. b. efferent control of a sense organ. c. the law of specific nerve energies. *d. a sense organ acting as a peripheral filter. 10. Sense organs do not faithfully report information about all the stimuli that impinge on them. Instead, they respond preferentially to a restricted range of one particular stimulus energy. Another way of saying this is that they a. are under efferent control. b. use across fiber patterning. *c. act as peripheral filters. d. show adaptation. 13. One kind of biological problem that sensory systems must solve is how to keep various sensory modalities separate. This is known as the problem of a. transduction. b. coding. *c. sensory specificity. d. serial processing. 16. The problem of how a stimulus produces a change in the membrane potential of a sensory cell is called the problem of a. coding. *b. transduction. c. adaptation. d. none of the above. 18. Transduction is the a. transport of vesicles in axons. *b. conversion of a stimulus into an electrical response of a sensory cell. c. physical deformation of a membrane by mechanical action. d. depolarization of a receptor cell by light. 19. A generator potential a. can be recorded in amacrine cells. b. can be recorded in intrafusal muscle. c. is the potential that generates spikes at synapses of sensory neurons. *d. is the potential produced by a stimulus impinging on a spiking sensory neuron. 22. Adaptation of a receptor cell refers to a(n) *a. decreasing response to a constant stimulus. b. increasing response as the stimulus declines. c. increasing response to repeated exposure to a stimulus. d. decreasing response to an increasing stimulus. 23. Adaptation in sensory neurons is *a. a gradual reduction in frequency of response with a constant stimulus. b. gradual reduction of sense organ sensitivity by action of the central nervous system. c. found only in mechanoreceptors. d. not observable in the generator potential. 26. A ______ receptor shows rapid adaptation. *a. phasic b. tonic c. linear d. spindle 27. A mechanoreceptor whose main function is to signal limb position at a joint is likely to be *a. tonic, because tonic receptors signal mainly static positions. b. phasic, because phasic receptors signal mainly static positions. c. tonic, because such receptors reflexly help maintain muscle tone. d. phasic, because such receptors reflexly help maintain proper phase during ongoing movements. 28. A mechanoreceptor whose main function is to signal rate of movement at a joint is likely to be a. tonic, because tonic receptors signal mainly dynamic movements. *b. phasic, because phasic receptors signal mainly dynamic movements. c. tonic, because such receptors reflexly help maintain muscle tone. d. phasic, because such receptors reflexly help maintain proper phase during ongoing movements. 29. A tonic mechanoreceptor a. usually has a very high threshold. b. is rarely under efferent control. *c. reports mainly about static positions. d. reports mainly about dynamic movements. 30. A phasic mechanoreceptor a. usually has a very high threshold. b. is rarely under efferent control. c. reports information mainly about static positions. *d. reports information mainly about dynamic movements. 31. In sensory systems, one mechanism for keeping a good sensitivity over a wide range of stimuli is called a. lateral inhibition. *b. range fractionation. c. efferent control. d. reafference. 35. In sensory systems, the mechanism for increasing contrast enhancement is called *a. lateral inhibition. b. range fractionation. c. efferent control. d. reafference. 37. A mechanism in sensory systems that acts to enhance contrast is a. adaptation. b. range fractionation. *c. lateral inhibition. d. topographical organization. 39. Somatotopic organization of the somatosensory cortex refers to the a. organization of different somatic senses into adjacent cortical columns. *b. point by point representation of the surface of the skin in the cortex. c. multimodal (e.g., touch, temperature, etc.) organization of the somatosensory cortex. d. projection of different sensory modalities (touch, temperature, etc.) to different regions of the somatosensory cortex. 41. Tonotopy could be used to describe a. muscle tonus being controlled by the CNS *b. the topographical organization of cells in the auditory cortex according to the frequency of sound stimuli that excites them. c. the fact that the tension of a muscle is regulated by spindle organs in parallel. d. none of the above. 43. The columnar organization of complex sensory systems is illustrated by the a. point to point representation of the surface of the body on the somatosensory center. b. hierarchical arrangement of simple, complex and hypercomplex cells in the visual cortex. c. dedication of specific columns in the spinal cord to specific senses. *d. cortical barrels in rat somatosensory cortex devoted to specific vibrissae. 45. Muller's law of specific nerve energies, restated in modern terms, claims that a. sensations are inherent in the stimuli that evoke them (e.g., only light can evoke visual sensations). *b. specific sensations arise from the type of sensory nerve stimulated, independent of the way it is stimulated. c. sensory nerves evoke sensations that are dependent on the stimuli that excite the nerves. d. each sense organ can respond only to one particular type of stimulus energy. 46. Using the same stimulus to excite different sense organs (e.g. pressure on the eyeball and on the skin) leads to different subjective sensations because a. different sense organs send different types of signals to the brain. b. different stimuli produce different patterns of impulses in different sense organs. *c. different sense organs send their stimuli to different decoding regions of the brain. d. none of the above.