Mastering A&P Chapter 10
Which primary-to-secondary neuron ratio would allow for the greatest receptive field sensitivity? A) 1:1 B) 1:2 C) 2:1 D) 3:1
A) 1:1
There are ________ primary taste (gustation) sensations. A) 5 B) 2 C) 400 D) 20 E) 4
A) 5
Which of the following are responsible for a receptor adapting to a stimulus? A) Na+ channel inactivation or K+ channel opening B) Na+ channel inactivation only C) opening of Na+ channels only D) K+ channel inactivation only E) opening of K+ channels only
A) Na+ channel inactivation or K+ channel opening
Which of the following statements regarding pathways for somatic perception projection is correct? A) Primary sensory neurons from the hands project to a specific region of the somatosensory cortex. B) The tertiary sensory neurons cross-over the body's midline. C) The longest of the secondary sensory neurons transmit fine touch and proprioceptive information. D) Primary sensory neurons that respond to cold sensation project to the same region of the somatosensory cortex. E) The synapse for the secondary to tertiary sensory neuron is within the medulla.
A) Primary sensory neurons from the hands project to a specific region of the somatosensory cortex.
Which cells release ATP when a ligand binds to its membrane receptor, and in which sense are these cells involved? A) Receptor cells; taste B) Hair cells; hearing C) Cones; vision D) Presynaptic cells; taste
A) Receptor cells; taste
Why do objects viewed underwater with a mask appear closer and larger than they really are? A) The mask provides additional refraction of light before it reaches the retina. B) Light traveling through the water scatters more than it does when moving through the air. C) Water is denser than the lens of the eye. D) Light moves more slowly through the water. E) The cornea does not function in water, and the light is not refracted as much.
A) The mask provides additional refraction of light before it reaches the retina.
Which of the following describes a depolarization? A) The membrane becomes less polarized. B) The membrane potential becomes more negative. C) The membrane potential becomes more polarized. D) The membrane, which was formerly not polarized, now is polarized.
A) The membrane becomes less polarized.
Which of the following does NOT describe graded potentials? A) They are always depolarizing. B) They are local changes. C) They are changes to the membrane potential. D) They vary with the intensity of the stimulus.
A) They are always depolarizing.
Greater visual acuity results from convergence of fewer number ofphotoreceptors onto retinal ganglion cells. A) True B) False
A) True
With the photoreceptor already stimulated with a moderate light intensity, a decreasein light intensity is required to open more sodium channels. A) True B) False
A) True
The function of the pigment melanin in the retina is to A) absorb light rays that are not absorbed by photoreceptors. B) absorb light rays that cause visual signals to go to the brain. C) determine eye color, depending on the amount of pigment present. D) help amplify signals in dim light.
A) absorb light rays that are not absorbed by photoreceptors.
The modality of a stimulus can be determined within the central nervous system by A) adequate stimulus for the sensory receptor cell. B) frequency coding. C) lateral inhibition. D) population coding.
A) adequate stimulus for the sensory receptor cell.
Which of the following would be an adequate stimulus for a mechanoreceptor? A) cell stretch B) pH C) photon of light D) cold temperature E) oxygen
A) cell stretch
The ability to distinguish different pitches (frequencies) of sound results from which of the following? A) changing sensitivity to pitch along the length of the basilar membrane B) the fact that individual hair cells have different sensitivities C) changing position of the middle ear bones, depending on sound frequency D) changing sensitivity to pitch along different parts of the tympanic membrane
A) changing sensitivity to pitch along the length of the basilar membrane
From an evolutionary perspective, the oldest sense is ________. A) chemoreception B) mechanoreception C) photoreception D) nociception
A) chemoreception
Sensory receptors that respond when body temperature is below normal are called A) cold receptors. B) photoreceptors. C) warm receptors. D) All receptors respond to temperatures above and below body temperature (no unique name).
A) cold receptors.
The pitch of a sound wave is related to its A) frequency. B) duration. C) decibels. D) amplitude.
A) frequency.
Photoreceptors secrete the neurotransmitter A) glutamate. B) acetylcholine. C) dopamine. D) norepinephrine.
A) glutamate.
The initial response to sweet and umami involves the binding to a receptor, which activates the protein ________ whereas salty and sour stimulate ________. A) gustduction, ion channels B) to open ion channels, G-protein coupled receptors C) tyrosine kinase, ion channels D) integrin, tyrosine kinase
A) gustduction, ion channels
The receptors of equilibrium and hearing are the A) hair cells. B) supporting cells. C) ampullae. D) saccules. E) utricles.
A) hair cells.
A decrease in the release of neurotransmitter from the photoreceptor would indicate a(n) A) increase in light intensity. B) decrease in light intensity. C) lack of light reaching the retina. D) change in focus of the lens onto a distant object.
A) increase in light intensity.
A neuron that has responded to a stimulus causes decreased activity in neighboring neurons in which process? A) lateral inhibition B) desensitization C) stimulus down-regulation D) habituation
A) lateral inhibition
Which of the following structures focuses light for clear vision? A) lens B) retina C) iris D) pupil
A) lens
Which receptors are the hair cells of the ear? A) mechanoreceptors B) audioreceptors C) chemoreceptors D) thermoreceptors
A) mechanoreceptors
The extension of the forebrain that receives odor input from the nose is the ________. A) olfactory bulb B) olfactory epithelium C) olfactory receptor D) vomeronasal organ
A) olfactory bulb
The central opening in the eye through which the light passes on to the retina is the A) pupil. B) fovea. C) cornea. D) lens. E) conjunctiva.
A) pupil.
The photosensitive pigment synthesized from vitamin A is A) retinal. B) opsin. C) rhodopsin. D) transducin. E) cGMP.
A) retinal.
Which structure(s) contain(s) receptors that detect rotation of the head? A) semicircular canals B) maculae C) saccule D) utricle
A) semicircular canals
Which of the following is NOT a somatosensory modality? A) vision B) proprioception C) nociception D) touch E) temperature
A) vision
Put these structures of the visual system in the order that they transmit visual information from the retina. 1. optic disk 2. visual cortex of the occipital lobe 3. optic chiasm 4. lateral geniculate body of the thalamus A) 1, 3, 2, 4 B) 1, 3, 4, 2 C) 3, 1, 2, 4 D) 1, 2, 3, 4 E) 3, 1, 4, 2
B) 1, 3, 4, 2
The following steps occur in rods when they are excited by a photon of light. Place them in the correct sequence. 1. Membrane sodium channels close. 2. cGMP is broken down. 3. The membrane hyperpolarizes and the rate of neurotransmitter release declines. 4. Transducin is activated. 5. Opsin is activated. A) 3, 5, 2, 1, 4 B) 5, 4, 2, 1, 3 C) 1, 5, 2, 4, 3 D) 4, 5, 2, 1, 3 E) 1, 3, 4, 5, 2
B) 5, 4, 2, 1, 3
Primary sensory neurons transmitting information on sweet and umami are activated by release of ________ whereas salty and sour are activated by release of ________. A) acetylcholine, calcium B) ATP, serotonin C) calcium, acetylcholine D) serotonin, ATP
B) ATP, serotonin
Which of the following would occur if you were to surgically remove the pigmented epithelium of the retina? A) A person would no longer be able to see in the dark. B) Entering light would be scattered across the retina and it would be difficult to obtain a sharp image. C) A person would no longer be able to process colors. D) Entering light would be scattered across the retina and a very sharp image would be obtained.
B) Entering light would be scattered across the retina and it would be difficult to obtain a sharp image.
________ hearing loss occurs because of damage to the structure of the inner ear. A) Conductive B) Sensorineural C) Central D) Mechanical
B) Sensorineural
Where do all tertiary somatic sensory neurons terminate? A) Hypothalamus B) Somatosensory cortex C) Thalamus D) Cerebellum
B) Somatosensory cortex
Vision is especially acute in the fovea and surrounding macula. This is due to a high density of cone cells and which other reason? A) There is an optimal mix of rods and cones. B) There are no blood vessels or neurons covering the cones. C) This is the only area of the retina with rods. D) The optic nerve exits the retina at the fovea providing an area especially sensitive to light.
B) There are no blood vessels or neurons covering the cones.
Why would a drug that enhances the kidney's ability to excrete water be given to someone that suffers from Ménière's disease? A) It will increase the concentration of crystals in the otolith. B) This treatment will decrease the amount of endolymph made. C) This treatment will increase the endolymph's salt content. D) This treatment will decrease blood pressure.
B) This treatment will decrease the amount of endolymph made.
What mechanism causes hair cell depolarization as stereocilia bend in response to sound waves? A) Rhodopsin absorbs energy to cause an increase in cGMP that opens cyclic nucleotide-gated channels. B) Tip links open ion channels, which causes membrane depolarization. C) Otoliths shift to open ion channels and depolarize hair cells. D) Receptor cells release ATP. Neighboring cells take up the ATP to generate action potentials.
B) Tip links open ion channels, which causes membrane depolarization.
A receptor potential is A) the resting membrane potential of a receptor cell. B) a graded potential. C) an action potential. D) always converted to an action potential in sensory receptor cells.
B) a graded potential.
Umami is A) another name for salty taste. B) a taste receptor cell activated by glutamate and nucleotides. C) the name of the ion channel activated by glutamate. D) a flavor enhancer that is part of olfaction.
B) a taste receptor cell activated by glutamate and nucleotides.
Phasic receptors A) are attune to parameters that the body must continuously assess. B) are quick to adapt to a particular stimulus intensity. C) slowly decrease the frequency of action potentials generated to a constant stimulus. D) once threshold is reached by a stimulus will always generate action potentials.
B) are quick to adapt to a particular stimulus intensity.
After an injury, Paul has difficulty recognizing and interpreting certain sounds. These symptoms imply damage to the A) middle ear. B) auditory cortex. C) cochlea. D) external ear.
B) auditory cortex.
If the sodium pump in the membranes of the photoreceptors were completely blocked, the result would be A) bright white light as all cones would be activated. B) darkness (blindness). C) grey images as only rods would function. D) an increase in visual acuity. E) the cells would not be able to produce glutamate.
B) darkness (blindness).
Which of the following structures is/are found in the retina? Check all that apply. A) blood vessels B) ganglion cells C) unipolar cells D) photoreceptors E) amacrine cells F) elastic fibers G) pigment epithelium H) bipolar cells I) horizontal cells
B) ganglion cells D) photoreceptors E) amacrine cells G) pigment epithelium H) bipolar cells I) horizontal cells
A decrease in ones perception of a stimulus whose intensity has not changed due to higher neural inhibition is A) adaptation. B) habituation. C) convergence. D) divergence.
B) habituation.
The highest frequency sound is detected by A) the frequency at which the stereocilia vibrate. B) hair cells located near the oval window end of the basilar membrane. C) unique hair cells located anywhere along the basilar membrane. D) hair cells located near the helicotrema end of the basilar membrane. E) hair cells located near the middle of the basilar membrane.
B) hair cells located near the oval window end of the basilar membrane.
The brain's association of activation of a receptor with the perception of a particular sensation is called A) modulating B) labeled line coding C )frequency D) locating
B) labeled line coding
In addition to temperature, cold receptors respond to A) capsaicin. B) menthol. C) water. D) alcohol.
B) menthol.
For a person suffering from ________, the focal point of the object is focused in front of the retina leading to blurring of distant objects. A) hyperopia B) myopia C) presbyopia D) astigmatism
B) myopia
Which of the following would be an adequate stimulus for a chemoreceptor? A) cell stretch B) oxygen C) photon of light D) cold temperature E) vibration
B) oxygen
A graded change in membrane potential within a sensory receptor cell is always called a(n) A) action potential. B) receptor potential. C) depolarization. D) hyperpolarization.
B) receptor potential.
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.
B) slowly decrease the frequency of action potentials generated to a constant stimulus.
The structure that overlies the organ of Corti and is attached to the tips of the hair cells is the A) endolymph. B) tectorial membrane. C) stapedius. D) perilymph. E) basilar membrane.
B) tectorial membrane.
Sensory neurons that maintain their firing as long as the stimulus is present are called ________ receptors. A) constant B) tonic C) continuous D) phasic
B) tonic
Which specific area of a neuron integrates signals? A) nucleus B) trigger zone C) axon D) dendrites
B) trigger zone
Human eyes are sensitive to light in the visible spectrum between the wavelengths of A) 1 to 400 nm. B) 500 to 1000 nm. C) 400 to 750 nm. D) 1000 to 1400 nm.
C) 400 to 750 nm.
Which accurately describes the stimulus threshold for cones? A) Cones have a low threshold, therefore they require a large amount of light to be activated. B) Cones have a high threshold, therefore they require a small amount of light to be activated. C) Cones have a high threshold, therefore they require a large amount of light to be activated. D) Cones have a low threshold, therefore they require a small amount of light to be activated.
C) Cones have a high threshold, therefore they require a large amount of light to be activated.
Which change in an olfactory sensory neuron occurs when an odorant binds to a receptor? A) Gs proteins are activated, which increase PKA activity leading to enzyme phosphorylation, the generation of an action potential. B) Gs protein increase ATP concentration leading to greater transport and release of neurotransmitter at the axon terminus. C) Golf proteins are activated, which increase cAMP and open cAMP-gated cation channels. D) Golf proteins cause hyperpolarization of the sensory olfactory neurons leading to increased signaling to the olfactory cortex.
C) Golf proteins are activated, which increase cAMP and open cAMP-gated cation channels.
What is the significance of the neuronal circuit setup of the retina? A) It allows for a pathway of feedback between the optic nerve and the photoreceptors. B) It allows for a single photoreceptor to stimulate hundreds of ganglion cells. C) It allows for a single multipolar neuron to process the signal from hundreds of different photoreceptors. D) It takes a small light signal and amplifies it before it reaches the brain.
C) It allows for a single multipolar neuron to process the signal from hundreds of different photoreceptors.
With Anant's symptoms of dizziness and low buzzing in his ear, is it certain that he has Ménière's disease? A) Yes; Ménière's disease is the only condition that will cause these symptoms. B) No; this is not a condition associated with Ménière's disease. C) No; it is possible that it could be positional vertigo.
C) No; it is possible that it could be positional vertigo.
________ receptors are sensory receptors that respond to changes in a stimulus by altering their firing which rapidly stops as the stimulus is maintained. A) Tonic B) Constant C) Phasic D) Integrating
C) Phasic
Which of the following correctly describes how a photoreceptor responds to light? A) The receptor depolarizes, producing a graded potential but not an action potential. B) The receptor depolarizes, producing an action potential. C) The receptor hyperpolarizes, decreasing the amount of neurotransmitter it releases. D) The receptor either depolarizes or hyperpolarizes, depending upon the predominant color in the light.
C) The receptor hyperpolarizes, decreasing the amount of neurotransmitter it releases.
Beta-endorphin is produced from the same prohormone as A) aldosterone. B) insulin. C) adrenocorticotropin (ACTH). D) glucagon. E) thyroxine.
C) adrenocorticotropin (ACTH).
The loudness or intensity of a sound wave is related to its A) frequency. B) duration. C) amplitude. D) pitch.
C) amplitude.
Which of the following structures contains sensory receptors for hearing? A) semicircular canals B) tympanic membrane C) cochlea D) eustachian tube (anatomically called the pharyngotympanic tube)
C) cochlea
The ciliary muscle helps to A) control the amount of light reaching the retina. B) move the eyeball. C) control the shape of the lens. D) control the production of aqueous humor.
C) control the shape of the lens.
Light entering an eye first passes through this cell layer of the retina: A) bipolar. B) photoreceptor. C) ganglion. D) horizontal.
C) ganglion.
When the intensity of the appropriate stimulus was increased, the amplitude of the response _______. A) decreased B) did not change C) increased D) was zero
C) increased
When Golf is activated, which of the following steps in the olfactory cells contribute to their depolarization? A) increases in the closure of cAMP gated cation channels only B) increases in cAMP concentrations only C) increases in adenylate cyclase activity and cAMP concentrations D) increases in adenylate cyclase activity, cAMP concentrations and closure of cAMP gated cation channels E) increases in adenylate cyclase only
C) increases in adenylate cyclase activity and cAMP concentrations
Which of the following types of receptors are involved in hearing? A) chemoreceptors B) thermoreceptors C) mechanoreceptors D) photoreceptors
C) mechanoreceptors
Which sensory pathway is the only one that does NOT synapse in the thalamus? A) vision B) gustation C) olfaction D) auditory
C) olfaction
Which of the following responded to a chemical stimulus? A) free nerve ending B) Pacinian corpuscle C) olfactory receptor D) both the Pacinian corpuscle and the olfactory receptor
C) olfactory receptor
Neuronal cells that are short-lived and therefore are frequently replaced are A) nociceptors. B) Pacinian corpuscles. C) olfactory receptors. D) gustatory receptors. E) retinal cells.
C) olfactory receptors.
Chemicals such as histamine, prostaglandins, serotonin, and substance P A) only inhibit nociceptors. B) sensitize, activate and inhibit nociceptors. C) only sensitize and activate nociceptors. D) only activate nociceptors. E) only sensitize nociceptors.
C) only sensitize and activate nociceptors.
The two-point discrimination test A) is used to test for hearing disorders. B) is used to determine clarity of vision. C) provides a measure of receptive field size for touch receptors. D) monitors the activity of taste buds. E) provides information about olfactory receptors.
C) provides a measure of receptive field size for touch receptors.
The receptor potential is generated at the _______. A) output region B) conducting region C) receiving region D) secretory region
C) receiving region
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) latency. B) tonic reception. C) referred pain. D) adaptation. E) analgesia.
C) referred pain.
Collateral pathways take vestibular receptor signals from the medulla to the A) thalamus only. B) cerebellum only. C) reticular formation and cerebellum. D) reticular formation only. E) thalamus and reticular formation.
C) reticular formation and cerebellum.
Sensory transduction is defined as _______. A) a change in the amplitude of a receptor potential B) the conversion of a light stimulus into pain C) the conversion of a stimulus to a change in membrane potential D) the disappearance of the perception of a stimulus
C) the conversion of a stimulus to a change in membrane potential
Accommodation describes the focusing of light on the retina by changing A) distance of the retina from the lens. B) the shape of the cornea. C) the shape of the lens. D) pupillary diameter.
C) the shape of the lens.
Sound waves are converted into mechanical movements (vibrations) by the A) cochlea. B) malleus. C) tympanic membrane. D) round window. E) oval window.
C) tympanic membrane.
Which of the following describes one of the symptoms associated with Ménière's disease and what sensory system of the body does it afflict? A) tinnitus; the sensations associated with taste B) nausea; general sensation at the level of the digestive system C) vertigo; balance and equilibrium by means of the ear D) dizziness; visual sensations
C) vertigo; balance and equilibrium by means of the ear
________ is released from type II cells to stimulate primary gustatory neurons. A) Acetylcholine B) Glutamine C) Gustducin D) ATP E) Serotonin
D) ATP
Identify the FALSE statement regarding sensory receptor cells. A) Threshold is the minimal stimulus intensity required to generate an action potential. B) A graded potential is referred to as a receptor potential. C )Sensory transduction converts stimulus energy into a receptor potential. D) Each type of sensory receptor responds only to the stimulus that defines the receptor. E) Many sensory receptor cells are NOT nerve cells.
D) Each type of sensory receptor responds only to the stimulus that defines the receptor.
Baroreceptors in the aortic arch and carotid bodies are mechanoreceptors that respond to the stretch that occurs in these arterial walls with changes in blood pressure. If pressure changes rapidly, the baroreceptors initiate a feedback mechanism that reduces blood pressure; however, if pressure changes slowly, as in developing hypertension, the receptors do not respond. Given this information, the baroreceptors are most likely which type of receptor? A) Adaptive receptors B) Discriminating receptors C) Tonic receptors D) Phasic receptors
D) Phasic receptors
The receptor potential _______. A) can be graded with stimulus intensity B) amplitude can vary with the stimulus intensity C) requires the appropriate stimulus D) amplitude can vary with the stimulus intensity, requires the appropriate stimulus and can be graded with a stimulus intensity
D) amplitude can vary with the stimulus intensity, requires the appropriate stimulus and can be graded with a stimulus intensity
Activation of Golf in the olfactory receptor cells causes ________ to open, which causes the frequency of action potentials to ________. A) cAMP gated cation channels, decrease B) cAMP gated anion channels, decrease C) cAMP gated anion channels, increase D) cAMP gated cation channels, increase
D) cAMP gated cation channels, increase
On a dark night, the rods have a high concentration of A) opsin. B) cAMP. C) kinase. D) cGMP.
D) cGMP.
As an object moves closer to the eye, the ciliary muscle ________ making the lens ________ in order to keep the object in focus. A) relaxes, thinner B) relaxes, thicker C) contracts, thinner D) contracts, thicker
D) contracts, thicker
A receptor potential is a type of ________ potential. A) action B) threshold C) resting D) graded
D) graded
Signal transduction in the type II taste cells relies on the G protein A) Ggus. B) transducin. C) Golf. D) gustducin.
D) gustducin.
Convergence describes A) how receptive fields can overlap with one another. B) the reason why receptive fields are so small. C) how one primary sensory receptor neurons synapses with a secondary neuron. D) how multiple primary sensory neurons synapse on a single secondary neuron.
D) how multiple primary sensory neurons synapse on a single secondary neuron.
For astronauts in space, the otoliths in the macula would respond to A) rotational acceleration only. B) linear acceleration and head position. C) head position only. D) linear acceleration only.
D) linear acceleration only.
Louder noises result in action potentials in the sensory neuron that are A) taller. B) less frequent. C) broader. D) more frequent. E) shorter.
D) more frequent.
Which of the following can be mediated by nociceptors? A) touch B) proprioception C) temperature D) pain and itch
D) pain and itch
A(n) ________ is a single energy packet of visible light. A) neutron B) electron C) proton D) photon
D) photon
The intensity of a stimulus can be determined within the central nervous system by A) population coding only. B) labeled line coding and/or frequency coding. C) labeled line coding only. D) population coding and/or frequency coding. E) frequency coding only.
D) population coding and/or frequency coding.
Endolymph is a unique fluid in the cochlear duct that contains more ________ and less ________ than the typical extracellular fluid. A) calcium, chlorine B) potassium, calcium C) sodium, chlorine D) potassium, sodium
D) potassium, sodium
The ion channels that transduce the vibration of the cochlea into receptor potentials are located on the A) helicotrema. B) cochlear duct. C) basilar membrane. D) stereocilia. E) tectorial membrane.
D) stereocilia.
With the exception of olfaction, all sensory pathways first travel to the ________, which acts as a relay and processing station. A) hypothalamus B) cerebrum C) medulla oblongata D) thalamus E) cerebellum
D) thalamus
Which of the following was able to detect pressure? A) Pacinian corpuscle B) olfactory receptor C) free nerve ending D) the Pacinian corpuscle and the free nerve ending
D) the Pacinian corpuscle and the free nerve ending
A blind spot in the retina occurs where A) the fovea is located. B) rod cells are clustered to form the macula. C) amacrine cells are located. D) the optic nerve leaves the eye. E) ganglion cells synapse with bipolar cells.
D) the optic nerve leaves the eye.
The bones within the middle ear connect the A) cochlea to the tympanic membrane. B) tympanic membrane to the round window. C) cochlea to the oval window. D) tympanic membrane to the oval window. E) oval window to the round window.
D) tympanic membrane to the oval window.
Which special sense would be most affected by a vitamin A deficiency? A) audition B) equilibrium C) gustation D) vision
D) vision
Put these structures of the visual system in the order that they transmit light to the retina. 1. lens 2. aqueous humor 3. cornea 4. vitreous humor A) 1, 4, 3, 2 B) 3, 4, 1, 2 C) 1, 2, 3, 4 D) 2, 3, 4, 1 E) 3, 2, 1, 4
E) 3, 2, 1, 4
A viral infection involving the vestibular nuclei may result in A) loss of sight. B) loss of hearing. C) local paralysis. D) high blood pressure. E) a sense of dizziness.
E) a sense of dizziness.
The primary purpose of the middle ear bony structures (maleus, incus and stapes) is to A) transmit otitis media to the cochlea. B) dampen the vibration as it conducts to the cochlea. C) equalize pressure in the middle ear. D) transduce the sound waves into vibration. E) amplify the vibration as it conducts to the cochlea.
E) amplify the vibration as it conducts to the cochlea.
An area of the retina that contains only cones and is the site of sharpest vision is the A) optic disc. B) inner segment. C) outer segment. D) tapetum lucidum. E) fovea.
E) fovea.
Nociceptors are responsible for the perception of A) pain and skin stretch. B) skin stretch only. C) pain only. D) itch only. E) pain and itch.
E) pain and itch.
A sudden flash of bright light would cause A) sympathetic activation to contract the pupillary constrictor muscles. B) sympathetic activation to contract the pupillary dilator muscles. C) parasympathetic activation to contract the pupillary dilator muscles. D) contraction of the ciliary muscle. E) parasympathetic activation to contract the pupillary constrictor muscles.
E) parasympathetic activation to contract the pupillary constrictor muscles.
Inhibiting adenyl cyclase in olfactory sensory neurons would A) expand the range of sensitivity of these receptors. B) convert the olfactory receptors from phasic to tonic receptors. C) increase the sensitivity of these receptors. D) have no effect on these receptors. E) reduce the sensitivity of these receptors.
E) reduce the sensitivity of these receptors.
When a rod located in the retina is stimulated by light, A) the release of neurotransmitter increases. B) the activity of transducin decreases. C) the inactive form of retinal associates with bleached opsin. D) the cell depolarizes. E) the intracellular concentration of cGMP decreases.
E) the intracellular concentration of cGMP decreases.