Sensory MCQ

Question 1

Which of the following statements is CORRECT? Primary sensory neurons are
A neurons that facilitate communication between the enteric nervous system and the
peripheral nervous system
B neurons belonging to the somatic division of the peripheral nervous system only
C afferent neurons which can detect sensory stimuli and relay the information to the brain
D neurons that integrate information over many other neurons and provide feedback to the
brain
E neurons that take signals from the brain to the periphery

Answer 1

C

Question 2

Lateral inhibition
A improves the strength of the signal
B limits the tonic adaptation to strong stimuli
C improves the temporal resolution of the signal
D limits the interference of overlapping receptive fields
E avoids crosstalk between different senses

Answer 2

D

Question 3

Hair cells are specialised receptor cells. Which of the following statements does NOT apply to
hair cells?
A Hair cells are polarised and respond to one direction of movement
B Hair cells transduce mechanical energy to electrical signal
C The stereocilia are linked together by tip links
D Hair cells are tuned to a specific frequency of stimulation
E Hair cells possess specialised stereocilia and kinocilia

Answer 3

D

Question 4

Which of the following statements about vision is INCORRECT?
A Muscles in the eye can flatten the lens to change its focal length
B Horizontal cells connect and integrate the input from multiple photoreceptors
C Cones are more sensitive to light than rods
D The cornea is transparent
E The ratio of responses between cones of different types is used to perceive colour

Answer 4

C

Question 5

Sound transduction is achieved
A via mechanically-gated cation channels, which open and close depending on the direction
of bending
B via mechanically-gated cation channels which open continuously while a sound is
detected
C in the organ of Corti, by direct stimulation of the cochlear nerve
D via chemically-gated cation channels, which are opened by sound particles
E via chemically-gated cation channels, which open when the stereocilia are bent

Answer 5

A

Question 6

Which of the following structures is NOT part of the vestibular anatomy?
A utricle
B saccule
C semicircular canal
D ampullae
E monolith

Answer 6

E

Question 7

When a physician tests the knee-jerk, which types of neurons and pathways are involved?
A mechanoreceptor neurons, interneurons and efferent neurons in a reflex arc
B mechanoreceptor neurons and interneurons of the general somatic pathway
C mechanoreceptor and nociceptor neurons, interneurons and efferent neurons in a reflex
arc
D nociceptor neurons and interneurons of the general somatic pathway
E nociceptor neurons, interneurons and efferent neurons in a reflex arc

Answer 7

A

Question 8

Which of the following receptors does NOT belong to the solute senses class?
A olfactory receptor
B photoreceptor
C chemoreceptor
D taste receptor
E pain receptor

Answer 8

E

Question 9

Lateral inhibition between adjacent receptors will
A ensure a precise timing of the stimulus
B improve the adaptation of the receptors
C improve the acuity of receptors
D avoid saturating the receptors
E ensure the univariance of the response

Answer 9

C

Question 10

Once a stimulus passes the threshold of activation of a receptor, its potential represents the
A frequency of the stimulus
B location of the stimulus
C duration of the stimulus
D intensity of the stimulus
E modality of the stimulus

Answer 10

D

Question 11

The direction of high frequency sound is estimated by the difference of
A intensity between our two ears
B intensity between beginning and end of the cochlea
C timing between beginning and end of the cochlea
D frequency between our two ears
E timing between our two ears

Answer 11

A

Question 12

Which of the following statments about maintaining our balance to the vestibular system is INCORRECT?
A Otoliths are made of calcium carbonate crystals
B The parieto-insular cortex disambiguates the acceleration stimulus
C Otoliths detect linear acceleration
D Semicircular canals detect rotational acceleration
E The vestibular system sensory receptors are mechanotransductive hair cells

Answer 12

B

Question 13

Which of the following is NOT a reason that the cornea is transparent?
A parallel organisation of the collagen
B ultraviolet lter
C immune privilege
D lack of coloured pigments
E lack of blood vessels

Answer 13

B

Question 14

The colours of an object are perceived by our brain due to
A a comparison of the response between different types of cones
B the cornea and lens refracting each wavelength on a different part of the retina
C specific pigments in different cones for each colour we can perceive
D a comparison of the response between rods and cones
E lateral inhibition between photoreceptors and amacrine cells

Answer 14

A

Question 15

When a sensory receptor is constantly stimulated, it
A inhibits all the downstream pathway to protect it
B burns out and stop responding
C only responds at the beginning of the stimulus
D adapts its response either rapidly or slowly
E slowly increases its response to accumulate the signal

Answer 15

D

Question 16

The human eye is a complex set of moving parts. How can the eye focus on an object?
A The cornea can change shape to change its refractive index
B The whole eye can change shape on demand to accommodate the focus needs
C Muscles can flatten the lens to change its focal length
D The fovea can be moved thanks to specific muscles
E The visual cortex can correct for the blurriness by comparing the image from both eyes

Answer 16

C

Question 17

Which retinal cell type connects and integrates the input from multiple photoreceptors?
A ganglion cells
B horizontal cells
C amacrine cells
D bipolar cells
E cones

Answer 17

B

Question 18

Photoreceptors are attuned to a range of wavelengths because of
A different photopigments in each photoreceptor
B the lens separating the wavelengths like a prism
C lateral inhibition between photoreceptors
D specific pigmented cells filtering the light before it reaches the photoreceptors
E feedback by ganglion cells

Answer 18

A

Question 19

Which of the following is NOT part of the signal transduction pathway of hair cells?
A bending of the cilia towards or away from the largest cilium
B Ca2+-dependent release of neurotransmitter from vesicles
C phosphorylation of Ca2+ channels regulating their open state
D action potentials generated by an afferent neuron
E mechanosensitive K+ channels opening or closing

Answer 19

C

Question 20

By which method is the frequency of sound encoded in the cochlea? [1.5 marks]
A rate coding, where the firing rate of hair cells increases with the frequency
B the frequency of sound is encoded downstream and not in the cochlea
C place coding, where the position of the responding hair cells depends on the frequency
D temporal coding, where the frequency of action potentials matches the frequency of the sound
E population coding, where the number of hair cells responding depends on the frequency

Answer 20

C

Question 21

What is an efference copy? The copy of
A motor commands sent to predict sensory feedback
B external information sensed by receptors
C actual sensory feedback from behaviour sent to the cortex
D sensory information sent to the cortex for analysis
E predicted sensory feedback from behaviour sent to the cortex

Answer 21

A

Question 22

Lateral inhibition
A limits the tonic adaptation to strong stimuli
B improves the temporal resolution of the signal
C limits the interference of overlapping receptive fields
D avoids crosstalk between different senses
E improves the strength of the signal

Answer 22

C

Question 23

When a physician tests the knee-jerk, which types of receptor neurons and pathways are
involved?
A mechanoreceptor neurons and interneurons of the general somatic pathway
B mechanoreceptor and nociceptor neurons, interneurons and efferent neurons in a reflex arc
C mechanoreceptor neurons, interneurons and efferent neurons in a reflex arc
D nociceptor neurons, interneurons and efferent neurons in a reflex arc
E nociceptor neurons and interneurons of the general somatic pathway

Answer 23

C

Question 24

In the dark, why is color vision lacking?
A Pupillary dilation causes less light to be focused on the fovea
B Reduced visual pigments are more sensitive to colour
C Neural adaptation limits information processing
D Cones are tonic receptors that adapt slowly
E Cones have a low sensitivity

Answer 24

E

Question 25

How do we perceive colours?
A We compare the ratio of responses between rods and cones
B Our lenses refract each colour differently, and we measure the angle of the light
C We compare the ratio of responses between cones of different types
D We have a cone specific for each colour we perceive
E Each colour hits the retina with a delay, so we use coincidence detectors

Answer 25

C

Question 26

Hair cells are specialised receptor cells. Which of the following statements does NOT apply to hair cells?
A They transduce mechanical energy to electrical signal
B They are tuned to a specific frequency of stimulation
C They possess a specialised stereocilia, the kinocilium
D The stereocilia are linked together by tip links
E They are polarised and respond to one direction of movement

Answer 26

B

Question 27

By which method is the frequency of sound encoded in the cochlea?
A Population coding, where the number of hair cells responding depends on the frequency
B Rate coding, where the firing rate of hair cells increases with the frequency
C Place coding, where the position of the responding hair cells depends on the frequency
D Temporal coding, where the frequency of action potentials matches the frequency of the sound
E The frequency of sound is not encoded in the cochlea, but downstream

Answer 27

C

Question 28

What is an efference copy?
A the copy of actual sensory feedback from behavior sent to the cortex
B the copy of predicted sensory feedback from behavior sent to the cortex
C the copy of sensory information sent to the cortex for analysis
D the copy of motor commands sent to predict sensory feedback
E the copy of external information sensed by receptors

Answer 28

D

Question 29

Sensory stimuli are detected by receptor cells. Two general types of such cells exist, and they are separate receptor cells and modified nerve endings. Which of the following statements does NOT describe a separate receptor cell?
A The strength of the sensory stimulus determines the magnitude of the receptor potential
B Local depolarisation leads to action potentials
C Separate receptor cells communicate with afferent fibre endings via neurotransmitters
D When separate receptor cells detect a sensory stimulus, cation channels open
E Influx of Na+ ions leads to opening of voltage-gated calcium channels

Answer 29

B

Question 30

Lateral inhibition is a phenomenon found across different sensory systems. Which of the
following statements about lateral inhibition is CORRECT?
A It causes a low signal to noise ratio, as neurons are inhibited
B Inhibitory interneurons stop the transmission of the signal to second order neurons
C It causes the suppression of all senses except the one that is the most relevant to the situation
D It is a phenomenon which causes the inhibition of all transmission of signals from lateral
sides of the body
E It is a phenomenon which causes contrast enhancement, and is the result of an excited neuron inhibiting its neighbours

Answer 30

E

Question 31

Which cells in the retina generate action potentials?
A rods
B bipolar cells
C cones
D horizontal cells
E ganglion cells

Answer 31

E

Question 32

Which of the following statements regarding vision is CORRECT?
A Cones are more sensitive to light than rods
B Action potentials in a cone are directly proportional to the number of photons absorbed
in the cone
C Horizontal cells integrate over ganglion cells and communicate with higher visual areas
in the brain
D The light travels through the ganglion cell and inner nuclear layers before it reaches the
photoreceptors
E Rods are mostly found in the fovea

Answer 32

D

Question 33

Which of the following statements about colour vision is CORRECT? Colour vision is
A achieved by the comparison of the output of rods and cones
B an exact representation of the physical properties of the environment
C dependent on cones sensitive to unltraviolet, blue and green light
D identical for different observers
E achieved by the comparison of the signals from L, M and S cones

Answer 33

E

Question 34

Hair cells are involved in hearing. Which of the following statements is INCORRECT?
A Outer hair cells enhance the signal, while inner hair cells transduce the signal
B Inner hair cells are responsible for hearing
C Inner hair cells have mechanically gated cation channels, while outer hair cells have
chemically gated channels
D There are three rows of outer hair cells
E The receptor potential alternates between depolarising and hyperpolarising with the
frequency of the sound

Answer 34

C

Question 35

The ear and vestibular system rely on the same receptor type. Which of the following statements is INCORRECT?
A In both senses, movement of fluid causes the relevant mechanical stimulus to activate hair
cells
B In the vestibular system (but not the inner ear), there are two types of hair cells. Outer
hair cells change their length to fine-tune the properties of the inner hair cells
C Tip links connect stereocilia so that all channels open when the stereocilia are bent
D In both senses, hair cells have mechanically gated potassium channels
E In the inner ear (but not the vestibular system), there are two types of hair cells. Outer
hair cells change their length to fine-tune the properties of the inner hair cells

Answer 35

E

Question 36

A sensory signal (whether chemical, auditory, visual etc.) can only be detected by the relevant sensory neuron if:
A there are no other signals present
B the signal to noise ratio is high
C the observer is awake
D the signal to noise ratio is low
E the afferent neuron is depolarised

Answer 36

D

Question 37

Which of the following statements about receptor adaptation is CORRECT?
A Tonic receptors adapt rapidly and phasic receptors adapt slowly
B Tonic receptors do not adapt at all and phasic receptors adapt slowly
C Phasic receptors adapt rapidly and tonic receptors never adapt
D Phasic receptors adapt rapidly and tonic receptors adapt slowly
E Both tonic and phasic receptors adapt slowly in most cases, but tonic receptors sometimes do not adapt at all

Answer 37

E

Question 38

Which is NOT part of the vestibular anatomy? [1.5 marks]
A ampullae
B saccule
C utricle
D vitriol
E semicircular canal

Answer 38

D

Question 39

We can maintain our balance thanks to the vestibular system. Which statement about the
vestibular system is FALSE? [1.5 marks]
A Semicircular canals detect rotational acceleration
B Otoliths detect linear acceleration
C The vestibular system sensory receptors are mechanotransductive hair cells
D The Parieto-insular cortex disambiguates the acceleration stimulus
E Otoliths are made of calcium carbonate crystals

Answer 39

D

Question 40

Which following statement is NOT part of hair cells’ signal transduction? [1.5 marks]
A Bending of the cilia towards or away from the largest cilium
B Phosphorylation of Ca2+ channels regulates their open state
C Mechanosensitive K+ channels opening or closing
D Ca2+ dependent release of neurotransmitter vesicles
E Action potentials are generated by an afferent neuron

Answer 40

B