Deck 6: Sensory Physiology

Question 1

The process of transduction associated with membrane receptors is inextricably linked to

A) a stimulus interacting with peripheral membrane proteins.
B) ion channels present in the membrane.
C) the establishment of a transmembrane potential.
D) ions moving up their concentration gradient.
E) none of these.

Answer 1

ion channels present in the membrane.

Question 2

It is believed that the group of channels responsible for sensing osmotic stress evolved first. This group of channels are

A) mechanically gated.
B) ion gated.
C) voltage-gated.
D) ligand-gated.
E) receptor-activated.

Answer 2

mechanically gated.

Question 3

A receptor cell

A) is involved in converting stimulus energy into action potentials.
B) is specialized to respond to a particular sensory modality.
C) can often be found in a sense organ grouped with other cells responsive to the same adequate stimulus.
D) all of these.
E) none of these.

Answer 3

all of these.

Question 4

Which receptor for vibrations and pressure is found in birds?

A) Pacinian corpuscle
B) Herbst corpuscle
C) Avian corpuscle
D) tactile disc
E) none of these.

Question 5

One can categorize sensory receptors according to sensory modality. Which of the following is NOT a type of receptor?

A) photoreceptor
B) intelreceptor
C) mechanoreceptor
D) chemoreceptor
E) thermoreceptor

Question 6

Stimulus intensity is typically encoded in

A) action potential amplitude.
B) frequency of action potentials.
C) number of receptors activated.
D) Both action potential and amplitude and frequency.
E) Both action potential frequency and number of receptors stimulated.

Question 7

A tonic receptor

A) quickly adapts to a stimulus.
B) has an off response.
C) ignores continuous information.
D) all of these.
E) none of these.

Question 8

Which of the following statements about light detection is TRUE?

A) Light detection is synonymous with vision.
B) Light detection is always initiated in a rod or cone photoreceptor, though these need not be located in an eye.
C) Even in its most primitive form, light detection evolved in structures dedicated to this purpose.
D) Light detection evolved numerous times in a variety of structures.
E) None of these.

Question 9

Which of the following statements about eyespots is NOT true?

A) Eyespots contain photoreceptor cells.
B) Eyespots are found in planarians and cnidarians.
C) Eyespots contain pigments that assure only light coming from a particular direction is absorbed.
D) Eyespots form an image perceived by the animal's ganglion.
E) Eyespots have a large visual field to which they respond.

Question 10

Which of the following statements is NOT true?

A) The Amoeba is capable of responding to light.
B) The surface of rhabdomeric photoreceptors consists of parallel microvilli.
C) Due to the size of their visual field, pinhole eyes do not form images.
D) Recognition of predator-prey movement requires a visual system that permits the formation of an image.
E) Butterflies sense light with their genitalia.

Question 11

Pupillary constriction results from contraction of the ________ muscle of the iris as a consequence of ________ stimulation.

A) circular; sympathetic
B) circular ; parasympathetic
C) radial; sympathetic
D) radial; parasympathetic
E) suspensory; somatic motor

Question 12

Which of the following strategies do animals use to help protect the retina from damage due to ultraviolet radiation?

A) pigmented cornea
B) pigmented lens
C) pigmented oil droplets in the photoreceptor inner segments
D) all of these.
E) none of these.

Question 13

In mammals, contraction of the ciliary muscle of the eye leads to

A) decreased pupil size.
B) increased pupil size.
C) increased curvature of the lens.
D) decreased curvature of the lens.
E) squinting.

Question 14

Accommodation

A) is the processes focusing the visual image on the retina.
B) occurs in fish by moving the lens either forward or backward.
C) can be accomplished by changing the fluid volume in the optic chamber .
D) only two of these.
E) all three of these.

Question 15

Which of the following does NOT form one of the neural layers of the retina?

A) rod and cone photoreceptors
B) bipolar cells
C) retinal pigment epithelium
D) ganglion cells
E) All of these are components of the neural retina.

Question 16

The part of a visual photoreceptor in which the detection of light (signal transduction) is initiated is the

A) outer segment.
B) inner segment.
C) synaptic terminal.
D) nucleus.
E) Golgi stacks.

Question 17

The cyclic nucleotide whose modulation is most closely associated with phototransduction in vertebrates is

A) cGMP.
B) cCMP.
C) cAMP.
D) cTMP.
E) 5'-GMP.

Question 18

Transducin

A) activates adenylyl cyclase resulting in the formation of cAMP.
B) activated calcium-activated channels leading to depolarization of the receptor cell.
C) activates the messenger pathway leading to an increase in cGMP.
D) is found in the inner segment of photoreceptor cells.
E) is a G-protein.

Question 19

Which of the following features account(s) for the greater acuity that occurs in cones, relative to the rods?

A) Different cone opsins have different absorbance maxima for wavelengths of light.
B) There is little convergence in the cone system.
C) Cones are less sensitive (require a stronger stimulus) than rods.
D) All of these contribute to acuity.
E) None of these influence acuity.

Question 20

The term light adaptation refers to

A) the changes that occur in the visual pigment system when going from a dark into a light environment.
B) the evolutionary changes that enable a species to maintain a diurnal life style.
C) the changes that occur in visual pigment system when going from a light into a dark environment.
D) none of these.

Question 21

Which of the following pairs are NOT related in any way?

A) night blindness and retinene
B) dark adaptation and sunlight
C) long (L) cones and the color yellow
D) primates and trichromatic vision
E) cones and high visual sensitivity

Question 22

On-center ganglion cells _____________ their spike frequency when the center of their receptive field is stimulated by light.

A) increase
B) decrease
C) do not change

Question 23

Information from the medial retina of each eye crosses to the opposite side to join its corresponding lateral visual field at the level of the

A) optic chiasma.
B) optic nerve.
C) optic tract.
D) corpus callosum.
E) geniculate nucleus.

Question 24

The term optic radiations refers to

A) visual tracts that cross between the cerebral hemispheres.
B) fiber tracts carrying information in the visual pathways from the lateral geniculate nucleus of the thalamus to different zones in the cortex.
C) the evolution of diverse specialized organs for vision.
D) the radial muscles in the iris that enable dilation of the pupil.
E) the visual field associated with off-center ganglion cells.

Question 25

In which portion of the photoreceptor is the light detecting pigment found?

A) inner segment
B) outer segment
C) middle segment
D) synaptic segment
E) transducing segment

Question 26

Phototransduction in invertebrates differs from that in vertebrates in that in invertebrates

A) no G-proteins are involved.
B) no cation channels are involved.
C) no opsins are involved.
D) photoreceptors depolarize in response to stimulation.
E) first-order cells hyperpolarize in response to stimulation.

Question 27

Statocysts are sensory organs used to perceive

A) consciousness, or state of being.
B) an organism's orientation in space.
C) surface hardness.
D) none of the above.

Question 28

Which of the following pairs is NOT related?

A) Sour taste and blocking of K⁺ channels
B) Salty taste and ENaC channels
C) Umami taste and amino acids
D) Sweet taste and IP₃ induced release of calcium
E) none of these.

Question 29

The otolith organs are

A) the ampulla and the ventricle.
B) the uvula and the spicule.
C) the utricle and the saccule.
D) cupula and ampulla.

Question 30

In the mammalian vestibular apparatus, the ________ are used to detect ________ while the ________ are used to detect ________.

A) semicircular canals; angular acceleration; otolith organs; linear acceleration
B) semicircular canals; linear acceleration; otolith organs; angular acceleration
C) hair cells; linear acceleration; scale cells; angular acceleration
D) hair cells; angular acceleration; scale cells; linear acceleration

Question 31

The pitch of a sound is determined by the ________ of vibrations, and in that respect is most similar to the ________ of light.

A) amplitude; brightness
B) amplitude; wavelength
C) frequency; brightness
D) frequency; wavelength

Question 32

Which of the following statements is NOT true?

A) Taste and smell senses are highly variable in sensitivities among species.
B) The intraspecies roles of olfaction are largely mediated by pheromones.
C) Sensilla are specialized projections from the cuticle of insects and are involved in chemical sensing
D) In humans, the cortical gustatory area is located in the temporal lobe.
E) The modality for mammalian taste receptors is called a tastant.

Question 33

In the normal hearing pathway, sound waves have to pass from air to liquid as sound is transmitted from the external ear to the inner ear. This occurs as a result of

A) the increase in pressure on the oval window relative to the pressure on the tympanic membrane.
B) the increase in force applied to the oval window which is accomplished by the lever action of the inner ear ossicles.
C) the difference in surface areas of the tympanic membrane and the membrane of the oval window .
D) two of these.
E) all of these.

Question 34

The cochlea of each ear contains about 16,000 hair cells. Even though they are in the minority, it is the ____________ hair cells that are principally responsible for transducing sound waves into what we perceive as sound sensations.

A) outer
B) inner
C) utricular
D) saccular
E) ampullar

Question 35

Due in part to the physical properties of the basilar membrane, the cochlea is tuned so that

A) high amplitude sounds are perceived optimally at the base of the narrow end of the cochlea (toward the oval window).
B) low amplitude sounds are perceived optimally at the base of the narrow end of the cochlea (toward the oval window).
C) high frequency sounds are perceived optimally at the base of the narrow end of the cochlea (toward the oval window).
D) low frequency sounds are perceived optimally at the base of the narrow end of the cochlea (toward the oval window).

Question 36

The pitch of a sound is perceived in part due to frequency matching in the action potentials of the ________, and in part due to spatial (tonotopic) mapping of the ________.

A) hair cells; basilar membrane
B) hair cells; vestibular membrane
C) auditory neurons; basilar membrane
D) auditory neurons; vestibular membrane
E) auditory neurons; tympanic membrane

Question 37

Ion currents can be found in all vertebrates (eukaryotes) but not in prokaryotes.

Question 38

The detection of physical forces in the environment is most likely the most ancient of the senses.

Question 39

Evolutionary adaptations related to movement have had a significant impact on the size of the semicircular canals.

Question 40

Animal communication in oceans occurs best at low frequencies because salts in seawater
absorb high-frequency sounds.

Question 41

Most deep-sea dwelling organisms have evolved L (red) cones as a way to compensate
for the diminished penetration of blue wavelength light into the deep sea.

Question 42

Polarized light is used by some butterflies to find a mate.

Question 43

Light induced phototransduction in both compound eyes and vertebrate eyes involves
depolarization of the photoreceptors cells, rods and cones.

Question 44

Mammals have a cold-gated channel that is structurally similar to the heat-gated channel
used by pit vipers to locate their prey.

Question 45

Passive electroreception uses an electric organ located in the tail of certain fish.

Question 46

The vertebrate eye has a blind spot because it is formed through a series of invaginations
of the epidermis.

Question 47

Match each sentence with the most appropriate choice:

-Generator potential

A) Afferent neuron
B) Touch
C) Taste
D) Paramecium
E) Electric fields
F)Magnetic fields
G) Slowly adapting
H) Adequate stimulus
I) Receptor density
J) Compound eye

Question 48

Match each sentence with the most appropriate choice:

-Mechanoreceptor

A) Afferent neuron
B) Touch
C) Taste
D) Paramecium
E) Electric fields
F) Magnetic fields
G) Slowly adapting
H) Adequate stimulus
I) Receptor density
J) Compound eye

Question 49

Match each sentence with the most appropriate choice:

-Chemoreceptor

A) Afferent neuron
B) Touch
C) Taste
D) Paramecium
E) Electric fields
F) Magnetic fields
G) Slowly adapting
H) Adequate stimulus
I) Receptor density
J) Compound eye

Question 50

Match each sentence with the most appropriate choice:

-Thermally gated channels

A) Afferent neuron
B) Touch
C) Taste
D) Paramecium
E) Electric fields
F) Magnetic fields
G) Slowly adapting
H) Adequate stimulus
I) Receptor density
J) Compound eye

Question 51

Match each sentence with the most appropriate choice:

-Electroreceptors

A) Afferent neuron
B) Touch
C) Taste
D) Paramecium
E) Electric fields
F) Magnetic fields
G) Slowly adapting
H) Adequate stimulus
I) Receptor density
J) Compound eye

Question 52

Match each sentence with the most appropriate choice:

-Magnetoreceptor

A) Afferent neuron
B) Touch
C) Taste
D) Paramecium
E) Electric fields
F) Magnetic fields
G) Slowly adapting
H) Adequate stimulus
I) Receptor density
J) Compound eye

Question 53

Match each sentence with the most appropriate choice:

-Tonic

A) Afferent neuron
B) Touch
C) Taste
D) Paramecium
E) Electric fields
F) Magnetic fields
G) Slowly adapting
H) Adequate stimulus
I) Receptor density
J) Compound eye

Question 54

Match each sentence with the most appropriate choice:

-Sensory cell

A) Afferent neuron
B) Touch
C) Taste
D) Paramecium
E) Electric fields
F) Magnetic fields
G) Slowly adapting
H) Adequate stimulus
I) Receptor density
J) Compound eye

Question 55

Match each sentence with the most appropriate choice:

-Acuity

A) Afferent neuron
B) Touch
C) Taste
D) Paramecium
E) Electric fields
F) Magnetic fields
G) Slowly adapting
H) Adequate stimulus
I) Receptor density
J) Compound eye

Question 56

Match each sentence with the most appropriate choice:

-Ommatidia

A) Afferent neuron
B) Touch
C) Taste
D) Paramecium
E) Electric fields
F) Magnetic fields
G) Slowly adapting
H) Adequate stimulus
I) Receptor density
J) Compound eye

Question 57

Compare and contrast the development of the retina in cephalopods and humans.

Question 58

Considering how animals adapt through evolution to live in their environment, explain why whales lack blue cones. Would you expect this to reflect the condition of its common ancestor with terrestrial mammals, or would you consider this a derived trait?

Question 59

Describe and discuss how lateral inhibition would be involved in the localization of pain to an ingrown toenail on lateral side of your left big toe.

Question 60

Develop an argument that supports the following statement. Salt receptors provided an adaptive advantage to early humans?

Question 61

Experiencing pain through the fast pain pathway has the obvious benefit of eliciting a withdrawal reflex to prevent further damage from the painful stimulus. What benefit do you think might be derived from experiencing persistent dull pain through the slow pain pathway?