Deck 7: Sensory Systems

Question 1

Odorant receptors are

A)carbohydrates.
B)proteins.
C)nucleic acids.
D)lipids.

Answer 1

B

Question 2

When a sensory receptor is an afferent neuron,the membrane potential that is initiated by a stimulus is called a

A)generator potential.
B)receptor potential.
C)synaptic potential.
D)action potential.

Answer 2

A

Question 3

The epithelium of the vomeronasal organ is similar to the olfactory epithelium in which way?

A)Both express the same chemoreceptors.
B)physical location
C)Both activate the same signal transduction pathway.
D)none of the above

Answer 3

D

Question 4

Among vertebrates,taste buds share certain common features.Which of the following is FALSE?

A)They are onion shaped.
B)They have a pore that opens out to the surface of the body.
C)They have numerous microvilli on the apical surface.
D)They are single neurons.

Question 5

In arthropods,the primary olfactory organs are generally located on the

A)mandible.
B)tympanum.
C)ommatidia.
D)antennae.

Question 6

Bitter and sour tastes are generally associated with

A)carbohydrates.
B)proteins.
C)ions.
D)toxic substances.

Question 7

All sensory systems work in the same general way.They transduce an incoming stimulus into changes in membrane

A)potential.
B)capacitance.
C)refractory period.
D)fluidity.

Question 8

Which of the following statements is inaccurate with respect to the sensory system of katydids?

A)Katydids' ears are located in the bend on their front legs.
B)Katydids have excellent hearing.
C)Katydids' hearing is used to identify mating calls of members of their own species.
D)Katydids cannot detect any echolocation sounds made by different species,such as bats.

Question 9

Which of the following statements about taste is FALSE?

A)K⁺ conveys salty.
B)H⁺ conveys sour.
C)Sugars convey sweet.
D)Amino acids convey umami.

Question 10

Which of the following is NOT one of the steps of sensory processing?

A)transduction of the signal
B)transmission of the signal to the integrating center
C)perception of the stimulus at the integrating center
D)motor response to the signal

Question 11

For sensory receptor cells,the "threshold of detection" is the weakest stimulus that produces

A)a response.
B)a response 50 percent of the time.
C)a response 100 percent of the time.
D)a maximum response magnitude.

Question 12

In olfactory receptor cells,signal transduction cascades often follow this order:

A)receptor binding → G-protein activation → cAMP → cell depolarization
B)cell depolarization → increased intracellular Ca²⁺ → adenylate cyclase activation
C)receptor binding → opening ion channels → G protein activation → cell depolatization
D)cell depolarization → adenylate cyclase → G-protein activation → conformational change

Question 13

What defines a cell as an afferent neuron?

A)It has the capacity to respond to environmental stimuli.
B)It is located at the periphery.
C)It has an axon that carries information to integrating centers.
D)It has receptor proteins in its membrane.

Question 14

A sensory illusion called paradoxical cold happens when a point heat stimulus is applied to a cold patch of skin,and is perceived as cold,not hot.This illusion happens due to

A)labeled-line pathways.
B)population coding.
C)both heat and cold receptors on the same sensory neuron.
D)lateral inhibition.

Question 15

Advantages of populations of receptors,as opposed to individual receptors,include

A)improved sensory discrimination.
B)improved stimulus intensity.
C)improved signal firing rate.
D)all of the above

Question 16

In aquatic vertebrates,gustation always involves detecting sensations involved with

A)predators.
B)potential mates.
C)food.
D)all of the above

Question 17

Each olfactory neuron expresses __________ odorant receptor protein and each odorant receptor protein can recognize __________ odorant.

A)one;one
B)more than one;one
C)one;more than one
D)more than one;more than one

Question 18

Select the pair below that does not match.

A)chemoreceptors - detect chemicals
B)photoreceptors - detect light
C)mechanoreceptors - detect magnetic fields
D)thermoreceptors - detect temperature

Question 19

In the strategy named "range fractionation,"

A)individual receptor cells are sensitive to a small portion of the possible range of intensities,but multiple receptors cover different parts of the range.
B)individual receptor cells are sensitive to a large portion of the possible range of intensities.
C)there is a decrease in sensory discrimination.
D)populations of receptors hinder sensory discrimination.

Question 20

When a stimulus is continually applied but the action potential frequency declines,this is called

A)receptor attenuation.
B)receptor acclimation.
C)receptor accommodation.
D)receptor adaptation.

Question 21

In regards to hair cells involved in vertebrate hearing organs,we know that

A)stereocilia are connected to each other by small fibers.
B)mechanosensitive ion channels at the tips of stereocilia are all closed at rest.
C)the 9 + 2 arrangement of stereocilia allow for free bending to improve sound resolution.
D)their bending always causes an increase in firing in the primary afferent.

Question 22

Ruffini corpuscles are associated with __________ and detect __________.

A)the skin surface;light touch and pressure
B)hair follicles;changes in movement on the skin surface
C)connective tissue of skin;skin stretch
D)deep subcutaneous tissue,muscle,joints;deep pressure and touch

Question 23

Mechanoreceptors are important for

A)touch.
B)proprioception.
C)hearing.
D)all of the above

Question 24

Which of the following choices is FALSE? The chromophore

A)absorbs energy from photons.
B)is a derivative of vitamin D.
C)is covalently linked to a member of the opsin gene family.
D)plays a role in photoreceptor sensitivity to different colors.

Question 25

Which of the following structures from the vertebrate inner ear is NOT part of the vestibular apparatus?

A)ampulla
B)utricule
C)saccule
D)cochlea

Question 26

Merkel's disks are used by the visually impaired for reading Braille.One quality of the receptor that allows this is

A)a phasic firing.
B)small receptive field.
C)a special sensitivity to deep pressure on the skin.
D)a large dendritic tree.

Question 27

Which eye structure constricts or dilates to control the amount of light that enters the eye?

A)iris
B)pupil
C)retina
D)lens

Question 28

In the salamander,the sour taste receptor cells function by having an apically localized K⁺ channel that is blocked by protons.When protons are applied,what happens to the membrane potential and why?

A)Receptor depolarization because K⁺ permeability,which normally maintains a hyperpolarized resting state,is reduced.
B)Receptor hyperpolarization because H⁺ ions move into the cell and render it more positively charged.
C)Receptor hyperpolarization because the H⁺ ions outside the cell make the inside of the cell more negatively charged.
D)Nothing will happen until the G protein is activated.

Question 29

Which of the following choices is FALSE regarding rhabdomeric photoreception?

A)The absorption of light leads to cell hyperpolarization.
B)The opsins signal through a Gq protein.
C)A phospholipase C signal transduction cascade is activated.
D)Diacylglycerol affects the activity of a nonselective cation channel.

Question 30

If the orientation of your ears were changed so that your right ear still faced forward but your left ear faced backward,how would your ability to locate the direction of an auditory stimulus change?

A)improved ability to distinguish left from right
B)improved ability to distinguish above from below
C)improved ability to distinguish front from back
D)There would be no improved ability at all.

Question 31

Without a proprioceptive sense,you would NOT be able to

A)clap your hands behind your back.
B)feel grains of sand on your fingertips.
C)autonomically control blood pressure.
D)sense changes in temperature.

Question 32

The small bones in the mammalian middle ear are called:

A)malleus,incus,stapes.
B)stapes,ossicle,tectorus.
C)malleus,otolith,statocyst.
D)utricle,saccule,ampulla.

Question 33

A thin piece of dome-shaped cuticle was found near one of the joints in a cricket leg.When it was removed,the animal could no longer make coordinated movements,but it could still respond to the rapid approach of a predator.This structure is most likely a

A)trichoid sensilla.
B)campaniform sensilla.
C)joint capsule receptor.
D)muscle spindle.

Question 34

Which of the following lists is in the correct order? Sweet tastes are processed in the following way:

A)receptor binding,gustducin activated,adenylate cyclase activated,K⁺ channels close.
B)receptor binding,Na⁺ channels open,cell depolarizes.
C)gustducin activated,Ca²⁺ channels close,cell hyperpolarizes.
D)transducin activated,PLC activated,Ca²⁺ levels rise,neurotransmitter released.

Question 35

You are riding your bicycle over a very bumpy road,reading a street sign far ahead of you.Which sensory inputs are NOT required to accomplish this task?

A)proprioceptors
B)visual inputs
C)inner ear
D)All of the above are required.

Question 36

The hair cells of the mammalian cochlea are contained in the

A)vestibular duct.
B)tympanic membrane.
C)round window.
D)organ of Corti.

Question 37

Mechanoreceptors translate mechanical signals into electrical signals when pressure on the cell

A)activates a G protein signal transduction cascade.
B)disrupts stability of the lipid bilayer,causing ions to flow.
C)induces a conformational change in ion channels,allowing ions to flow.
D)induces a change in cell volume that disrupts ion balance.

Question 38

Which of the following choices is FALSE? Mammalian rods and cones differ in that rods

A)have fewer types of photopigment than cones.
B)have a slower response time than cones.
C)function better than cones in bright light.
D)integrate signals over a longer period than cones.

Question 39

Improving the resolving power of the compound eye would require

A)increasing the number of ommatidia.
B)increasing the size of each ommatidium.
C)decreasing the size of the pinhole opening on each ommatidia.
D)decreasing the thickness of the cornea.

Question 40

Which taste receptor does NOT use a G-protein-coupled receptor for activation?

A)bitter
B)sweet
C)salty
D)umami

Question 41

The top of a sensory cell's dynamic range can be limited by the firing frequency of the primary afferent neuron.The maximum frequency is set by the __________ period.

Question 42

Sensory cells that respond to more than one class of stimulus are called __________ receptors.

Question 43

Why is vision sharpest in the fovea?

A)It has more rods.
B)It has more cones.
C)There is less interference with overlying cells.
D)It contains the focal point.

Question 44

Some species of fish are able to produce electrical discharges.These fish

A)produce discharges continuously from their electric organ.
B)produce only weak discharges of approximately 1 volt.
C)have a specialized electric organ of highly derived nerve and muscle cells known as electrocytes.
D)are known as strongly electric fish.

Question 45

In terrestrial vertebrates,taste receptor cells are clustered into groups known as __________.

Question 46

In humans,tastes can be grouped into one of five classes,which are __________.(list all five)

Question 47

The focal point is the

A)point between the center of the lens and the retina.
B)point where light waves converge after passing through the lens.
C)small region in the center of the retina responsible for high-acuity vision.
D)narrow band of the electromagnetic spectrum that contains visible light.

Question 48

To help discriminate the location of a touch stimulus,neurons at the center of the receptive field can inhibit those at the edge,a process known as __________.

Question 49

Terrestrial vertebrates detect pheromones using an organ called the __________ organ.

Question 50

What is the main difference between "on" and "off" region receptive fields?

A)signal processing at the photoreceptor
B)the type of neurotransmitter released by the photoreceptor
C)the nature of the response of the bipolar cell to glutamate
D)the presence of horizontal cells

Question 51

In vertebrates,olfactory receptor cells are bipolar sensory neurons,but taste receptor cells are __________.

Question 52

__________ are a kind of receptor that respond to extremely strong stimuli,including those that may cause tissue damage.

Question 53

The __________ law describes the logarithmic relationship between stimulus magnitude and perceived stimulus intensity.

Question 54

There are two main types of mechanoreceptor proteins: epithelial sodium channels and __________.

Question 55

Touch and pressure receptors can be broadly grouped into three categories: tactile receptors,proprioceptors,and __________.

Question 56

In the vertebrate olfactory system,the olfactory receptor cells have one end in the olfactory epithelium,and the other end makes synapses with neurons in the __________ of the brain.

Question 57

To generate an optimal visual image,the focal point must fall on the

A)lens.
B)fovea.
C)retina.
D)cornea.

Question 58

In animals with binocular vision,it is true that

A)neurons from the retina of the right eye project to the left lateral geniculate nucleus.
B)neurons responding to the right visual fields project to the left lateral geniculate nucleus.
C)neurons of the nasal retina project to the left lateral geniculate nucleus.
D)neurons of the temporal retina project to the left lateral geniculate nucleus.

Question 59

In response to a stimulus,a signal transduction pathway is initiated,which ultimately leads to the opening or closing of __________.

Question 60

Stimulus intensity is normally coded by action potential_____________.

Question 61

Researchers are trying to determine the cause of circadian rhythm disruption in modern societies.They measured the hormone ________________ ,which is associated with sleep-wake cycles in humans.Levels of this hormone are high at night and lower during the day.

Question 62

List the four necessary steps that are required for sensory reception.Different receptors are used to detect different stimuli: Briefly describe three examples of stimulus modality.

Question 63

Briefly describe lateral inhibition.Why is it useful? Draw a figure if necessary.

Question 64

If all sensory signals are eventually transduced into the common action potential,then how do receptors encode stimulus modality? Give an example.

Question 65

Compound eyes are composed of many __________.

Question 66

Why is it so difficult to localize sound with only one ear? How does having two ears help to localize sound?

Question 67

Both the olfactory system and the gustatory system in vertebrates work by processing chemoreceptive signals.However,there are several differences between them.Describe/explain three differences.

Question 68

How does the mammalian eye focus an image? In your description,name the important physical structures in image formation,define the focal point,and explain what accommodation is and why it is important.

Question 69

In the mammalian inner ear,inner hair cells detect sounds,while outer hair cells __________.

Question 70

Fish,larval amphibians,and adult aquatic amphibians have cup-shaped organs called __________ that consist of mechanosensory hair cells to detect water movements such as those caused by potential predators.

Question 71

The organ of the inner ear of mammals that contains the hair cells is called the __________.

Question 72

Discuss how pheromones are used by (nonhuman)animals to communicate with members of their own species or with other species.Provide at least three examples to support your answer.

Question 73

In carp,the inner ear is connected to the swim bladder by a series of bones called __________.

Question 74

____________ are found in vertebrates and invertebrates,and are responsible for monitoring the position of the body.

Question 75

The compound called __________ can stimulate cold-sensitive neurons.

Question 76

It is late at night,and you are at the library doing some last-minute studying for your comparative physiology exam.You suddenly feel hungry,and you head to the vending machine to buy a snack.Explain the role of the following sensory structures/organs,and give an example of how/when they will be active during this task.
a.Merkel cell
b.Gustatory receptors (choose one)c.Macula of a utricle
d.Cone photoreceptor

Question 77

Generally,how do sensory neurons encode stimulus intensity? What is the dynamic range of a sensory neuron? How does range fractionation improve the dynamic range?

Question 78

The compound called __________ can stimulate warm-sensitive neurons.

Question 79

A tympanal organ functions as an insect __________.

Question 80

Invertebrates have organs called __________ that detect the orientation of their bodies with respect to gravity.