Exam 2 Quiz/Tophat Questions
Identify which statement(s) is/are FALSE about the medial superior olive? 1. Neurons in the medial superior olive (MSO) only fire action potentials when sound inputs arrive first to the nearest ear then the furthest ear 2. Neurons in the MSO only fire action potentials when sound inputs from right and left ear synapse on the neuron at the same time. 3. The MSO localizes sound in the environment based on the timing the sound is received 4. The MSO localizes sound in the environment based on sound intensity (level) of the two ears
1, 4
Listed below are the various components of the olfactory transduction process: 1. G-protein 2. Voltage-gated sodium channel 3. Calcium-activated chloride channel 4. cAMP-gated ion channel 5. Adenylyl cyclase III Which is the correct order in which these components are activated?
1, 5, 4, 3, 2
•Which of the following would cause depolarization of the photoreceptor? •A a phosphodiesterase inhibitor •B inhibition of cGMP •C Activation of G protein alpha subunits—caused by light •D Light—leads to hyperpolarization •E All of the above •F None of the above
A
•A neuron that contains glutamate in the presynaptic terminal will be a glutamatergic neuron. •A True •B False
B
As light intensity changes, the receptor potentials of cells within the retina also change. Which of the following pathways is true with decreased light intensity? A. Off Bipolar cells hyperpolarize as mGluR receptors are activated by glutamate and cause the conversion of cGMP to GMP. B. Channel rhodopsin has a conformational change from cis-retinal to trans-retinal, resulting in activation of the G protein transducin. C. Horizontal cells are directly stimulated to suppress action potentials from photoreceptor cells. D. Voltage-gated Ca++ channels in photoreceptors open and stimulate the release of glutamate into the synapse. E. Phosphodiesterase converts cGMP to GMP in the rods and causes cGMP-gated Na+/Ca++ channels to close.
D
When you stub your toe, you feel a sharp pain immediately but may also feel a throbbing, persistent pain for hours or days afterwards. Which of the following statements is/are true regarding how these pain signals are transduced? I. Transmission through Aδ fibers is responsible for the initial sharp pain II. Transmission by C fibers is responsible for the initial sharp pain III. TRP channels in free nerve endings are depolarized after activation by the mechanical stimulus IV. Myelination of C fibers allows for fast communication after receiving a stimulus
I, III
How does a lighter surround make a dark center seem even darker? I. Increased glutamate release from the surround photoreceptors. II. Decreased glutamate release from the surround photoreceptors III. Less GABA release from Horizontal cells onto the terminals of photoreceptors in the center pathway. IV. More GABA release from Horizontal cells onto the terminals of photoreceptors in the center pathway.
II, III
Which of the following statement(s) regarding mechanoreceptors is/are false? I. Merkel receptor receptive fields are small; therefore, they provide high spatial resolution. II. Meissner corpuscle receptive fields are large, but they are highly sensitive, therefore they have high spatial resolution. III. Although Pacinian corpuscle receptors are highly sensitive, they have huge receptive fields, therefore they have low spatial resolution. IV. Merkel and Ruffini receptors are expected to respond throughout the duration of a stimulus because they are slowly adapting receptors. V. Pacinian and Meissner receptors are expected to respond throughout the duration of a stimulus because they are rapidly adapting receptors.
II, V
Place the following events in the correct order . I. The basilar membrane vibration causes the tectorial membrane to move. II. Stretch activated tip links on the stereocilia cause an influx of K+ ions. III. Vibrations through the cochlea begin at the base and travel to the appropriate frequency on the tonotopic map for maximum vibration. IV. K+ ions depolarize hair cells, causing voltage-gated calcium channels to open and transmitter to be released. V. The movement of the tectorial membrane causes shearing force of the hair cells against the membrane.
III, I, V, II, IV
Which of the following cell types in the visual system express AMPA receptors? I. photoreceptors II. ON bipolar cells III. OFF bipolar cells IV. ganglion cells
III, IV
•Vertical plane sound localization (midbrain)
Inferior Colliculus
Interaural level difference
Lateral superior olive
interaural time difference
Medial superior olive
•primary visual cortex
Occipital lobe
•Primary somatosensory cortex
Parietal lobe
•Primary auditory cortex
Temporal lobe
All are true for otolith organs except: a. Na+ channels on vestibular hair cells open at rest due to tension on stretch channels b. kinocilium are oriented toward striola in utricle c. the utricle encodes linear movmenet such as quickly starting or stopping at traffic light d. movement against the kinocilium can both depolarize or hyperpolarize the hair cell
a
An OFF-ganglion cell is most depolarized when: A. It is dark in the center and light in the surround B. It is dark in the center and dark in the surround C. It is light in the center and light in the surround D. It is light in the center and dark in the surround
a
During a softball game Anna gets hit in the thigh by a bad pitch, and she immediately grabs her leg and starts rubbing it. She discovers that this helped to reduce the amount of pain that she experienced. Why is this the case? a. Skin mechanoreceptors have indirectly inhibited second order pain neurons in the spinal cord. b. C fibers from her skin are directly inhibited by touch and no longer transmit a pain signal to the brain. c. The C fibers on her skin are activated and directly inhibit second order neurons so no pain signal is transmitted. d. The inhibitory neurons that synapse onto second order pain neurons are firing less and reducing transmission of the pain signal to the brain. e. Anna is imagining things and her pain level is the same as when she was first hit by the ball.
a
Sam is determined that this is the year he will win the famous Pitt Chili Eating Contest. However, he is not known to play fair. Which of the following would be most effective at helping him withstand the heat from the Chile peppers, but not interfere with any other sensations? a) Blocking TRPV1 receptors on his tongue. b) Blocking voltage-gated sodium channels in his C fibers c) Blocking G-protein coupled receptors on his tongue d) Blocking mechanoreceptors in his Aδ fibers. e) None of the above would reduce his perception of the Chili peppers
a
The semicircular canals are largely insensitive to linear acceleration because... a. the forces produced by linear acceleration are the same on both sides of each cupula. b. the different hair cell orientations in the cupula cancel out any linear acceleration responses. c. forces generated by linear acceleration are never strong enough to bend hair cell bundles d. linear acceleration is not strong enough to exert a force on hair cells e. none of the above; semicircular canals are, in fact, highly sensitive to linear acceleration.
a
Which of the following is true for a sensory receptor potential but not true for a postsynaptic potential. a. it is always excitatory b. it can excitatory or inhibitory c. it is a graded potential, therefore proportional to the intensity of the stimulus d. if it is large enough to reach threshold it will trigger an action potential in the neuron e. all of the above are true only for sensory receptor potentials
a
all are true about semicircular canals except a. crista houses the hair cell bundle and the cupula houses the soma b. endolymph cannot flow through a denser cupula c. the hair cells of the semicircular canals can be depolarized or hyperpolarized d. hair cells of the canals cause vestibular afferents to die in response to acceleraiton and firing returns to resting levles during constant velocity
a
•Sound enters the cochlea through the _ and vibrates the ____. This vibration causes the __ to move, bending the stereocilia of the hair cell and initiating a(n) ____ potential in that cell. •A Oval window; basilar membrane; tectorial membrane; receptor •B Oval window; tectorial membrane; basilar membrane; action •C Round window; tectorial membrane; basilar membrane; receptor •D Round window; basilar membrane; tympanic membrane; receptor •E Oval window; basilar membrane; tympanic membrane; action
a
•Which of the following are common features of a receptor potential and a post synaptic potential? Choose all that apply. •Multiple answers:You can select more than one option •A Both types of potentials are graded •B They both occur primarily on dendrites •C They both result in an excitatory stimuli •D Both types of potentials can cause a neuron to fire an action potential •E All of the above are true (common features)
a, d
only releases neurotransmitter when there is an influx of K+
auditory
Harry has a medical condition where he has endolymph in his Tympanic Canal. Will his hearing be affected? a. Yes, his hair cells will stop firing acting potentials b. Yes, his hair cells will not repolarize c. Yes, his hair cell will not depolarize d. No, endolymph is normally found in the Tympanic Canal e. No, endolymph is found only in the vestibular system
b
In the lab, you identify a hair cell from a mouse that is releasing glutamate at rest, only releases graded potentials, hyperpolarizes when prodded, and is depolarized by potassium. What kind of hair cell have you isolated? a. Auditory hair cell b. Vestibular hair cell c. Olfactory receptor neuron d. A and b are both possible
b
Poor Sam has no magnocellular (M) ganglion cells. Which of the following difficulties does he most likely experience? A. Sam is color-blind B. Sam has difficulty identifying the speed and direction of moving objects C. Sam has difficulty identifying the shapes of objects D. Sam has difficulty identifying the size of objects E. None of the above
b
What statement(s) is/are true about bipolar cells? A. Increasing light intensity activates mGluRs on ON bipolar cells, resulting in their depolarization. B. Increasing light intensity decreases activation of mGluRs on ON bipolar cells, resulting in their depolarization. C. Increasing light intensity activates AMPA receptors on OFF bipolar cells, resulting in their depolarization. D. Increasing light intensity decreases activation of AMPA receptors on OFF bipolar cells, resulting in their depolarization. E. A and C are true F. B and D are true
b
_______ gives rise to tonotopy along the cochlea. a. The changing width and stiffness of the tectorial membrane b. The changing width and stiffness of the basilar membrane c. The speed at which sound waves propagate along the length of the cochlea d. The changing mechanical properties of the cochlear wall along the length of the cochlea e. The increasing density of the cochlear fluid along the length of the cochlea
b
•If the perilymph K+ concentration was increased slightly, what effect would it have on the hair cell? •A The hair cell would depolarize more slowly. •B The hair cell would repolarize more slowly. •C Neurotransmitter would not be released. •D There would be no effect
b
•If you block the activation of adenylyl cyclase, what will happen in an ORN? •A Voltage-gated sodium channels will open, and AP will fire •B A lack of cAMP would prevent activation of the Na+/Ca++ channel •C Potassium ions would leave the neuron, causing depolarization D There would be increased calcium levels, therefore increased activation of chloride channels
b
•Which of the following is true regarding the result(s) of endolymph movement on the cupula? •A With constant velocity spinning, there is slight movement toward the kinocilium, causing depolarization. •B With constant velocity spinning, there is no net movement, so endolymph and cupula return to rest. •C If rotational acceleration of endolymph causes the hair bundle to move toward the kinocilium, there is depolarization. •D If linear, orthogonal acceleration of endolymph causes the hair bundle to move toward the kinocilium, there is depolarization.
b, c
•Which of the following occur when the center is light and the surround is dark? Select all that apply. •A Center photoreceptor is depolarized •B Center photoreceptor is hyperpolarized •C Surround photoreceptor is depolarized •D Surround photoreceptor is hyperpolarized •E Horizontal cell is releasing GABA •F Horizontal cell is not releasing GABA
b, c, e
•Which sensory receptors fire action potentials? (select all that apply) •A Photoreceptors •B Mechanoreceptors •C Auditory hair cells •D Vestibular hair cells •E Taste receptors •F Olfactory receptor neurons •G Ganglion cells
b, f, g
The auditory hair-cell bodies are embedded in the ___________.
basilar membrane
Which of the following is true regarding the otolith organs? a. In the utricle the kinocilium are oriented away from the striola b. both the saccule and the utricle detect superior inferior movement c. during a head tilt the otolithic membrane exerts a "shearing" force on hair cells d. The striola is a straight line that cuts the utricle and saccule in half. e. All of the above are true
c
Which of the following statements accurately describes cortical mapping? a. The representation of the body in the somatosensory map is proportional to body surface area. b. Somatosensory representations are fixed and cannot change as a result of experience. c. The better the spatial accuracy, the larger the representation of that area in the somatosensory cortex d. All of the above e. a and b only
c
Which statement is true? A. The role of the lens is to narrow the light path and improve sharpness of objects B. Myopia is a result of light focusing behind the retina instead of focusing directly on the retina C. The role of retinal pigmented epithelium cells is to absorb light to prevent backscatter and remove and recycle photoreceptor discs D. Magnocellular (or M) ganglion cells have small receptive fields and are color insensitive E. In the Lateral Geniculate Nucleus, damage to the Parvocellular layers impairs perception of motion
c
•How is it possible that glutamate can have opposite effect on ON bipolar and OFF bipolar cells? •A glutamate is not released onto both kinds of cells at the same time •B a different form of glutamate is released onto the 2 cell types •C because the 2 cells types express different receptors •D glutamate is "activated" by light, therefore depolarizes ON cells •E Glutamate is released only onto ON cells
c
•Which of the following is true of vestibular hair cells, but NOT auditory hair cells •A They are depolarized by potassium influx •B They are repolarized by potassium efflux •C They release neurotransmitter at rest •D They fire action potentials when depolarized past their threshold potential
c
all are true about the otolith organs except: a. tonic response of vestibular afferent to head tilt lasts for the duration of the tilt b. can cause a depolarization or hyperpolarization of vestibular hair cells depending on orientation of kinocilium c. the otolithic membrane is less dense than the gelatinous level d. the preilymph has a high K+ relative to soma of hair cell
c, d
•What is true about organization of the visual system? •A Rods are responsible for color vision •B All vision information from the left eye goes to the right cortex •C All information from the left visual field goes to the right cortex •D All information from both eyes goes to both hemisphere's LGN—info from left goes to right brain vice versa; both eyes one visual field •E Photon binding increases glutamate release from photorecptors •F Photon binding decreases glutamate release from photoreceptors.
c, f
A sensory "receptor" potential is usually due to... a. resting or "leak" currents in the cell body. b. the activation of voltage-gated ion channels. c. the activation of ligand-gated ion channels. d. an external stimulus impinging upon sensory nerve endings. e. an internal stimulus modifying a synaptic signal between two interneurons.
d
Which of the following is/are true? a. The receptive field of a sensory neuron is the skin surface which when stimulated results in AP firing b. The extent of sensory neuron receptor ending branching determines the size of the receptive field c. Spatial accuracy is the ability to discern between two stimuli separated by distance d. All of the above e. B and C
d
Which statement is true about on and off coding? A. On cells hyperpolarize with increasing light intensity B. Off cells hyperpolarize with decreasing light intensity C. On bipolar cells fire more action potentials with increasing light intensity D. Off ganglion cells fire more action potentials with decreasing light intensity E. None of the above are true
d
all are true for vestibular ganglion neurons except a. they are bipolar cells b. the soma is in scarpa's ganglion c. they fire action potentials d. they send afferents to vestibular cortex
d
Which of the following is (are) a way that opioids can relieve pain? a. Binding to mu, delta and kappa receptors on a 1st order afferent neuron's terminal to reduce calcium influx b. Opening a potassium channel to produce an IPSP in the 2nd order pain neuron c. Increasing the duration of the action potential in the 1st order afferent neuron d. All of the above e. a and b only
e
You are falling asleep while watching TV, so your pillow ends up covering your right eye since you have laid down. If you can only see the TV with your left eye, what is true about your visual field? a. Only the right side of your visual cortex is receiving input from the TV b. Only the left side of your visual cortex is receiving input from the TV. c. Your left eye sends all of its visual input across the optic chiasm to the right side of the visual cortex. d. a and c are true e. all of the above are false
e
Sharp pain is known as the ________ pain involving _______, _________fibers. Longer, diffused pain is known as the _______ pain involving _____ , _________fibers.
first, myelinated, a delta, second, unmyelinated, C
Which sensory receptor(s) produce action potentials?
ganglion cells
produces graded potentials in response to a chemical
gustatory
•auditory part of thalamus, visual part of thalamus
medial geniculate nucleus
produces action potentials in response to chemical binding G-protein coupled receptor
olfaction
produces action potentials after opening of stretch receptors
somatosensory
In auditory and vestibular hair cells, potassium is responsible for both depolarization (due to influx) and repolarization (due to efflux)
true
releases neurotransmitter at rest and can increase/decrease release with K+ influx
vestibular
receptors hyperpolarize when bound by stimulus
visual