Deck 50: Sensory and Motor Mechanisms

Question 1

Stimuli alter the activity of excitable sensory cells via

A)integration.
B)transmission.
C)transduction.
D)transcription.
E)amplification.

Answer 1

C

Question 2

Statocysts contain cells that are

A)mechanoreceptors which function in orientation to gravity.
B)chemoreceptors used in selecting migration routes.
C)photoreceptors used in setting biological rhythms.
D)thermoreceptors used in prey detection.
E)chemoreceptors used in acid-base balance.

Answer 2

A

Question 3

Action potentials differ from receptor potentials in that

A)receptor potentials are all or none events.
B)action potentials are graded.
C)receptor potentials are graded.
D)action potentials occur more frequently.
E)action potentials occur with greater magnitude.

Answer 3

C

Question 4

Dizziness is a perceived sensation that can occur when

A)the hair cells in the cochlea move more than their normal limits.
B)moving fluid in the semicircular canals encounters a stationary cupula.
C)rods and cones provide information that does not correspond with information received by cochlear hair cells.
D)the basilar membrane makes physical contact with the tectorial membrane.
E)the utricle is horizontal but the saccule is vertical.

Question 5

Sound waves arriving at a listener first strike the

A)tectorial membrane.
B)tympanic membrane.
C)round-window membrane.
D)hair cell membrane.
E)basilar membrane.

Question 6

The pathway leading to the perception of sound by mammals begins with the

A)hair cells of the organ of Corti, which rests on the basilar membrane, coming in contact with the tectorial membrane.
B)hair cells of the organ of Corti, which rests on the tympanic membrane, coming in contact with the tectorial membrane.
C)hair cells of the organ of Corti, which rests on the tectorial membrane, coming in contact with the basilar membrane.
D)hair cells of the organ of Corti coming in contact with the tectorial membrane as a result of fluid waves in the cochlea causing vibrations in the round window.
E)hair cells on the tympanic membrane that stimulate the tectorial membrane neurons, leading to the auditory section of the brain.

Question 7

Tastes and smells are distinct kinds of environmental information in that

A)neural projections from taste receptors reach different parts of the brain than the neural projections from olfactory receptors.
B)the single area of the cerebral cortex that receives smell and taste signals can distinguish tastes and smells by the pattern of action potentials received.
C)tastant molecules are airborne, whereas odorant molecules are dissolved in fluids.
D)distinguishing tastant molecules requires learning, whereas smell discrimination is an innate process.
E)odorants bind to receptor proteins, but none of the tastant stimuli bind to receptors.

Question 8

Immediately after putting on a shirt,your skin might feel itchy.However,this perception soon fades due to

A)sensory adaptation.
B)accommodation.
C)the increase of transduction.
D)reduced motor unit recruitment.
E)reduced receptor amplification.

Question 9

A given photon of light may trigger an action potential with thousands of times more energy because the signal strength is magnified by

A)the receptor.
B)a G protein.
C)an enzyme-catalyzed reaction.
D)sensory adaptation.
E)triggering several receptors at once.

Question 10

An earthworm without a statocyst would not be able to

A)move.
B)sense light.
C)hear.
D)orient with respect to gravity.
E)respond to touch.

Question 11

The cochlea is an organ of auditory transduction that contains

A)fluid and cells that can undergo mechanosensory transduction.
B)air and cells that produce wax.
C)air and small bones that vibrate in response to sound waves.
D)fluid with stacks of chemosensory cells.
E)air and statocysts activated by movement.

Question 12

Statoliths are similar to otoliths in that both

A)are grains of sand.
B)stimulate hair-like mechanoreceptors.
C)are located in statocysts.
D)are located in the cochlea.
E)are located in the lateral line system.

Question 13

The correct sequence of sensory processing is

A)sensory adaptation → stimulus reception → sensory transduction → sensory perception.
B)stimulus reception → sensory transduction → sensory perception → sensory adaptation.
C)sensory perception → stimulus reception → sensory transduction → sensory adaptation.
D)sensory perception → sensory transduction → stimulus reception → sensory adaptation.
E)stimulus reception → sensory perception → sensory adaptation → sensory transduction.

Question 14

The cellular membrane across which ion flow varies during auditory transduction is the

A)tectorial membrane.
B)tympanic membrane.
C)round-window membrane.
D)hair cell membrane.
E)basilar membrane.

Question 15

Choose the correct sequence of the following events leading to the sensory processing of a stimulus.
1)transmission
2)transduction
3)integration
4)amplification

A)1 → 2 → 3 → 4
B)1 → 4 → 2 → 3
C)2 → 4 → 1 → 3
D)3 → 1 → 2 → 4
E)3 → 1 → 4 → 2

Question 16

Artificial electrical stimulation of a human's capsaicin-sensitive neurons would likely produce the sensation of

A)cold temperature.
B)hot temperature.
C)tactile stimulus.
D)odour of pepper.
E)deep pressure.

Question 17

When ascending in an airplane,you feel your ears pop.This equalization of pressure is due to which auditory structure?

A)tectorial membrane
B)stapes
C)cochlea
D)utricle
E)Eustachian tube

Question 18

The muscle spindle is

A)an actin-myosin complex.
B)a troponin-tropomyosin complex.
C)axons wound around muscle fibres.
D)a group of dendrite-encircled muscle fibres.
E)a muscle cell that makes up a muscle group.

Question 19

The 11 pairs of appendages projecting from the rostral area of star-nosed moles are

A)chemosensory structures.
B)tactile structures.
C)olfactory structures.
D)highly sensitive photoreceptors.
E)gustatory structures.

Question 20

Artificial electrical stimulation of a human's menthol-sensitive neurons would likely produce the sensation of

A)cold temperature.
B)hot temperature.
C)tactile stimulus.
D)odour of pepper.
E)deep pressure.

Question 21

Which of the following matches is incorrect?

A)compound eye - bee
B)ocelli - Planarian
C)compound eye - Annelid
D)single lens - spider
E)single lens - house fly

Question 22

The lateral line system in fish transduces sensory information in a manner that,among these choices,is most similar to

A)human vision.
B)human olfaction.
C)human gustation.
D)human vestibular sense.
E)human thermoreception.

Question 23

Rods exposed to light will

A)depolarize due to the opening of sodium channels.
B)hyperpolarize due to the closing of sodium channels.
C)depolarize due to the opening of potassium channels.
D)hyperpolarize due to the closing of potassium channels.
E)fire one action potential for each photon received.

Question 24

The generation of action potentials in olfactory neurons initiated by odours drawn in the nasal cavity is an example of

A)perception.
B)sensory transduction.
C)sensory adaptation.
D)habituation.
E)lateral inhibition.

Question 25

Mechanoreceptors that react to low frequency waves are part of the

A)human sense of taste.
B)pain receptors in birds.
C)human sense of smell.
D)lateral line systems in fish.
E)eyes in arthropods.

Question 26

It can be very difficult to select an angle for sneaking up to a grasshopper to catch it because grasshoppers have

A)excellent hearing for detecting predators.
B)compound eyes with multiple ommatidia.
C)eyes with multiple fovea.
D)a camera-like eye with multiple fovea.
E)binocular vision.

Question 27

Corneal surgery is now routinely performed to change the shape of the cornea and improve vision.Why is this surgery beneficial?

A)improves the circulation of nutrients to the eye
B)improves the focusing of light onto the retina
C)decreases the amount of light entering the eye
D)increases the sensitivity of the photoreceptors
E)decreases the pressure in the eye

Question 28

In the human retina,

A)cone cells can detect colour, but rod cells cannot.
B)cone cells are more sensitive than rod cells to light.
C)cone cells, but not rod cells, have a visual pigment.
D)rod cells are most highly concentrated in the centre of the retina.
E)rod cells require higher illumination for stimulation than do cone cells.

Question 29

Lateral inhibition via amacrine cells in the mammalian retina

A)underlies habituation of vision.
B)enhances visual contrast.
C)prevents bleaching in bright light.
D)is required for colour vision to occur.
E)recycles neurotransmitter molecules.

Question 30

Sensory-transducing cells that fire both graded potentials and action potentials are found in

A)vision.
B)gustation.
C)olfaction.
D)audition.

Question 31

Tastes and smells are similar in that

A)both types of stimuli are present in thousands of different chemicals.
B)both types of stimuli must be dissolved in a body fluid before they can be detected.
C)both types of stimuli are proteins (that is, molecules of very large size and high molecular weight).
D)both types of stimuli evoke action potentials in the cells to which they bind.
E)any given stimulus for one system evokes a response from the other system.

Question 32

Receptor proteins for the neurotransmitter molecules released by rods and cones are found on

A)ganglion cells.
B)horizontal cells.
C)amacrine cells.
D)bipolar cells.
E)lateral cells.

Question 33

The blind spot in the human retina is the location that has the collected axons of

A)ganglion cells.
B)bipolar cells.
C)primary visual cortex.
D)optic chiasma.
E)lateral geniculate nuclei.

Question 34

What structures would neurobiologists look for if they are interested in determining if an animal can see in color?

A)opsins
B)electroreceptors
C)pupil
D)lens
E)optic nerve

Question 35

Sensory transduction of light/dark information in the vertebrate retina is accomplished by

A)ganglion cells.
B)amacrine cells.
C)bipolar cells.
D)horizontal cells.
E)rods and cones.

Question 36

The olfactory bulbs are located

A)in the nasal cavity.
B)in the anterior pituitary gland.
C)in the posterior pituitary gland.
D)in the brain.
E)in the brainstem.

Question 37

Compared to viewing a distant object,viewing an object held within 5 cm of the eye requires a lens that

A)has been flattened, as a result of contraction of the ciliary muscles.
B)has been made more spherical, as a result of contraction of the ciliary muscles.
C)has been flattened, as a result of relaxation of the ciliary muscles.
D)has been made more spherical, as a result of relaxation of the ciliary muscles.
E)does not change its shape.

Question 38

The perceived pitch of a sound depends on

A)which part of the tympanic membrane is being vibrated by sound waves.
B)which part of the oval window produces waves in the cochlear fluid.
C)which region of the basilar membrane was set in motion.
D)whether or not the sound moves the incus, malleus, and stapes.
E)the listener having had training in music.

Question 39

The sand grains or other dense materials resting on mechanoreceptors used by most invertebrates to sense gravity are called

A)cochlea.
B)statoliths.
C)stapes.
D)pinnae.
E)antennae.

Question 40

A rod exposed to light will

A)fire action potentials that will increase its release of glutamate.
B)undergo a graded depolarization that will increase its release of glutamate.
C)undergo a graded hyperpolarization that will increase its release of glutamate.
D)undergo a graded depolarization that will decrease its release of glutamate.
E)undergo a graded hyperpolarization that will decrease its release of glutamate.

Question 41

Proteins coded by a very large family of related genes are active in the sensory transduction of

A)gustatory stimuli.
B)olfactory stimuli.
C)visual stimuli.
D)auditory stimuli.
E)stimuli related to the position of the head.

Question 42

Myasthenia gravis is a form of muscle paralysis in which

A)motor neurons lose their myelination and the ability to rapidly fire action potentials.
B)acetylcholine receptors are destroyed by an overactive immune system.
C)ATP production becomes uncoupled from mitochondrial electron transport.
D)the spinal cord is infected with a virus that attacks muscle stretch receptors.
E)troponin molecules become unable to bind calcium ions.

Question 43

A ligand for the umami receptor in the sense of taste is

A)glucose.
B)sodium ions.
C)potassium ions.
D)hydrogen ions.
E)monosodium glutamate.

Question 44

The "motor unit" in vertebrate skeletal muscle refers to

A)one actin binding site and its myosin partner.
B)one sarcomere and all of its actin and myosin filaments.
C)one myofibril and all of its sarcomeres.
D)one motor neuron and all of the muscle fibres on which it has synapses.
E)an entire muscle.

Question 45

The muscles of a recently deceased human can remain in a contracted state,termed rigor mortis,for several hours,due to the lack of

A)phosphorylated myosin.
B)ATP needed to break actin-myosin bonds.
C)calcium ions needed to bind to troponin.
D)oxygen supplies needed for myoglobin.
E)sodium ions needed to fire action potentials.

Question 46

The contraction of skeletal muscles is based on

A)actin filaments coiling up to become shorter.
B)myosin filaments coiling up to become shorter.
C)actin and myosin filaments both coiling up to become shorter.
D)actin cross-bridges binding to myosin and then flexing.
E)myosin cross-bridges binding to actin and then flexing.

Question 47

A skeletal muscle deprived of adequate ATP supplies will

A)immediately relax.
B)release all actin-myosin bonds.
C)enter a state where actin and myosin are unable to separate.
D)fire many more action potentials than usual and enter a state of "rigour."
E)sequester all free calcium ions into the sarcoplasmic reticulum.

Question 48

Most of the ATP supplies for a skeletal muscle undergoing one hour of sustained exercise come from

A)creatine phosphate.
B)glycolysis.
C)substrate phosphorylation.
D)oxidative phosphorylation.
E)de novo synthesis.

Question 49

The calcium ions released into the cytosol during excitation of skeletal muscle bind to

A)troponin.
B)tropomyosin.
C)actin.
D)myosin.
E)transverse tubules.

Question 50

The ratio of expressed receptor types to taste cells is

A)~10:1
B)~100:1
C)~1000:1
D)1:1
E)1:~100

Question 51

A skeletal muscle with abnormally low levels of calcium ions would be impaired in

A)ATP hydrolysis.
B)the initiation of an action potential.
C)maintaining its resting membrane potential.
D)initiating contraction.
E)its ability to sustain glycolysis.

Question 52

Skeletal muscle contraction begins when calcium ions bind to

A)energized cross-bridges.
B)myosin.
C)actin.
D)tropomyosin.
E)troponin.

Question 53

Calcium ions initiate sliding of filaments in skeletal muscles by

A)breaking the actin-myosin cross-bridges.
B)binding to the troponin complex, which then relocates tropomyosin.
C)transmitting action potentials across the neuromuscular junction.
D)spreading action potentials through the T tubules.
E)reestablishing the resting membrane potential following an action potential.

Question 54

Compared to oxidative skeletal muscle fibres,those classified as glycolytic typically have

A)a higher concentration of myoglobin.
B)a higher density of mitochondria.
C)a darker visual appearance.
D)a smaller diameter.
E)less resistance to fatigue.

Question 55

Umami perception follows the oral presence of

A)sugar water.
B)a rich chocolate flavour.
C)a savory and complex cheese.
D)acidic orange juice.
E)salt water.

Question 56

Olfaction differs from gustation in that

A)gustation depends on cilia.
B)gustation depends on chemoreceptors.
C)the sensory cells of olfaction are neurons.
D)tastants are dissolved in mucus.
E)the sensory cells of gustation are neurons.

Question 57

During muscle contraction,
I)actin filaments cross the M line.
II)the Z lines move closer together.
III)myosin forms cross bridges with actin.
IV)actin and myosin coil around each other.

A)I, II, and IV
B)I, II, and III
C)I and II
D)II only
E)I only

Question 58

Most of the chemosensory neurons arising in the nasal cavity have axonal projections that terminate in the

A)gustatory complex.
B)anterior hypothalamus.
C)olfactory bulb.
D)occipital lobe.
E)posterior pituitary gland.

Question 59

Muscle cells are stimulated by neurotransmitters released from the synaptic terminals of

A)T tubules.
B)motor neuron axons.
C)sensory neuron axons.
D)motor neuron dendrites.
E)sensory neuron dendrites.

Question 60

In a relaxed skeletal muscle,actin is not chemically bound to

A)myosin.
B)troponin.
C)tropomyosin.
D)Z lines.
E)sarcoplasmic reticulum

Question 61

Use the following figure to answer the questions below.

Myosin filaments without actin overlap are in which section of the figure?

A)A
B)B
C)C
D)D
E)E

Question 62

Use the following figure to answer the questions below.

Overlapping actin and myosin filaments are found in which section of the figure?

A)A
B)B
C)C
D)D
E)E

Question 63

The structure diagrammed in the figure is the

A)neuromast.
B)statocyst.
C)taste bud.
D)ommatidium.
E)olfactory bulb.

Question 64

Use the following figure to answer the questions below.

The structure pictured in the figure is found in

A)skeletal muscles and smooth muscles.
B)cardiac muscles and skeletal muscles.
C)smooth muscles and cardiac muscles.
D)smooth muscles, skeletal muscles, and cardiac muscles.
E)smooth muscles.

Question 65

Among these choices,the most energetically efficient locomotion per unit mass is likely

A)running by a 50-gram rodent.
B)running by a 40-kg ungulate.
C)flying by a 100-g bird.
D)swimming by a 10-g minnow (bony fish).
E)swimming by a 100-kg tuna (bony fish).

Question 66

A ball-and-socket joint connects

A)the radius to the ulna.
B)the radius to the humerus.
C)the ulna to the humerus.
D)the humerus to the scapula.
E)the radius to the scapula.

Question 67

Which of the following is the correct sequence that describes the excitation and contraction of a skeletal muscle fibre?
1)Tropomyosin shifts and unblocks the cross-bridge binding sites.
2)Calcium is released and binds to the troponin complex.
3)Transverse tubules depolarize the sarcoplasmic reticulum.
4)The thin filaments are ratcheted across the thick filaments by the heads of the myosin molecules using energy from ATP.
5)An action potential in a motor neuron causes the axon to release acetylcholine,which depolarizes the muscle cell membrane.

A)1 → 2 → 3 → 4 → 5
B)2 → 1 → 3 → 5 → 4
C)2 → 3 → 4 → 1 → 5
D)5 → 3 → 1 → 2 → 4
E)5 → 3 → 2 → 1 → 4

Question 68

The following questions refer to this diagram of the ear.

The structure involved in equalizing the pressure between the ear and the atmosphere is represented by number

A)7
B)1
C)8
D)9
E)10

Question 69

The following questions refer to this diagram of the ear.

Hair cells are found in structures represented by numbers

A)1 and 2
B)3 and 4
C)5 and 7
D)6 and 8
E)9 and 10

Question 70

The following questions refer to this diagram of the ear.

The organ of Corti is represented by which number?

A)3
B)4
C)5
D)6
E)7

Question 71

Chitin is a major component of

A)the skeleton of mammals.
B)the hydrostatic skeletons of earthworms.
C)the exoskeleton of insects.
D)the body hairs of mammals.
E)the skeleton in birds.

Question 72

The hydrostatic skeleton of the earthworm allows it to move around in its environment by

A)walking on its limbs.
B)crawling with its feet.
C)swimming with its setae.
D)using peristaltic contractions of its circular and longitudinal muscles.
E)alternating contractions and relaxations of its flagellae.

Question 73

Action potentials in the heart move from one contractile cell to the next via

A)chemical synapses using acetylcholine.
B)chemical synapses using norepinephrine.
C)electrical synapses using gap junctions.
D)myelinated motor neurons.
E)non-myelinated motor neurons.

Question 74

Skeletal,cardiac,and smooth muscle all have

A)A bands and I bands.
B)transverse tubules.
C)gap junctions.
D)motor units.
E)thick and thin filaments.

Question 75

An endoskeleton is the primary body support for the

A)annelids, including earthworms.
B)insects, including beetles.
C)cartilaginous fishes, including sharks.
D)bivalves, including clams.
E)crustaceans, including lobsters.

Question 76

Sustained muscle contraction without relaxation between successive stimuli is called

A)tonus.
B)tetanus.
C)an all-or-none response.
D)fatigue.
E)a spasm.

Question 77

The following questions refer to this diagram of the ear.

The sense of head motion begins with sensory transduction by the structures at which numbers?

A)2, 3, and 4
B)2, 5, and 7
C)4
D)5
E)7 and 8

Question 78

Calcium ions regulate contraction of smooth muscle cells by binding to

A)troponin.
B)tropomyosin.
C)actin.
D)myosin.
E)calmodulin.

Question 79

The lumen of the transverse tubules of skeletal muscles contains

A)extracellular fluid.
B)cytosol.
C)actin.
D)myosin.
E)sarcomeres.

Question 80

The following questions refer to this diagram of the ear.

Vibrations of the tympanic membrane to the oval window are transmitted by the structures at which numbers?

A)1, 2, 3, and 4
B)2, 3, and 4
C)3 and 4
D)4
E)5