Chapter 50 Questions

Question 1

Which of the following sensory receptors is incorrectly paired with its category?

a. hair cell—mechanoreceptor
b. snake pit organ—thermoreceptor
c. taste receptor—chemoreceptor
d. olfactory receptor—electromagnetic receptor

Answer 1

d. olfactory receptor—electromagnetic receptor

Question 2

The middle ear converts

a. air pressure waves to fluid pressure waves.
b. air pressure waves to nerve impulses.
c. fluid pressure waves to nerve impulses.
d. pressure waves to hair cell movements.

Answer 2

a. air pressure waves to fluid pressure waves.

Question 3

During the contraction of a vertebrate skeletal muscle fiber, calcium ions

a. break cross-bridges as a cofactor in hydrolysis of ATP.
b. bind with troponin, changing its shape so that the myosin-binding sites on actin are exposed.
c. transmit action potentials from the motor neuron to the muscle fiber.
d. spread action potentials through the T tubules.

Answer 3

b. bind with troponin, changing its shape so that the myosin-binding sites on actin are exposed.

Question 4

Which sensory distinction is not encoded by a difference in neuron identity?

a. white and red
b. red and green
c. loud and faint
d. salty and sweet

Answer 4

c. loud and faint

Question 5

The transduction of sound waves into action potentials occurs

a. in the tectorial membrane as it is stimulated by hair cells.
b. when hair cells are bent against the tectorial membrane, causing them to depolarize and release neurotransmitter that stimulates sensory neurons.
c. as the basilar membrane vibrates at different frequencies in response to the varying volume of sounds.
d. within the middle ear as the vibrations are amplified by the malleus, incus, and stapes.

Answer 5

b. when hair cells are bent against the tectorial membrane, causing them to depolarize and release neurotransmitter that stimulates sensory neurons.

Question 6

Although some sharks close their eyes just before they bite, their bites are on target. Researchers have noted that sharks often misdirect their bites at metal objects and that they can find batteries buried under sand. This evidence suggests that sharks keep track of their prey during the split second before they bite in the same way that

a. a rattlesnake finds a mouse in its burrow.
b. an insect avoids being stepped on.
c. a star-nosed mole locates its prey in tunnels.
d. a platypus locates its prey in a muddy river.

Answer 6

d. a platypus locates its prey in a muddy river.

Question 7

In cell signaling pathways, signal transduction often involves

a. nucleotides as well as enzymes and other proteins.
b. information moving in a single step from the cell surface to the nucleus.
c. G protein coupled receptors in the nucleus.
d. a 1:1 ratio of input to output.

Answer 7

a. nucleotides as well as enzymes and other proteins.

Question 8

Which region of the brain receives sensory information after processing and then issues motor output?

a. temporal lobe
b. parietal lobe
c. occipital lobe
d. frontal lobe

Answer 8

d. frontal lobe

Question 9

Actin forms microfilaments that contain

a. many identical subunits assembled into a double helix.
b. side-by-side polypeptides stretching the length of the filament.
c. chemical bonds fixing each subunit in place.
d. spring-like polypeptides that lengthen and shorten.

Answer 9

a. many identical subunits assembled into a double helix.

Question 10

A thermosensory neuron in the skin converts heat energy to nerve impulses via a conversion called _____.

a. sensation
b. reception
c. integration
d. sensory transduction
e. perception

Answer 10

d. sensory transduction

Question 11

Sensory adaptation is apparent when _____.

a. sitting in a hot room causes you to sweat
b. a person is no longer aware of a heavy necklace that was put on earlier in the day
c. your initial dive into a cold swimming pool gives your skin “goose bumps”
d. water above a certain temperature stimulates pain receptors rather than temperature receptors
e. individuals who live in cold climates have fewer cold receptors in their skin

Answer 11

b. a person is no longer aware of a heavy necklace that was put on earlier in the day

Question 12

Sensory transduction in the auditory system is much like transduction of _____.

a. odorant molecules binding to receptor proteins on olfactory neurons
b. sweet-tasting molecules binding to receptor proteins on the tongue
c. visual stimuli by rods in the retina
d. mechanosensory stimuli
e. hormones binding to receptor proteins

Answer 12

d. mechanosensory stimuli

Question 13

The energy for sensory transduction by the lateral line system in fish comes from _____.

a. electrical signals in the water
b. odors of prey
c. thermal energy
d. water movements
e. high-frequency sound waves transmitted in water

Answer 13

d. water movements

Question 14

The visual information used by honeybees includes these elements that are not apparent to humans.

a. warmth and cations
b. electrical auras and infrared wavelengths
c. vibrating molecules and all ranges of the energy spectrum
d. single photons and infrared radiation
e. the ability to distinguish ultraviolet radiation and 300 flashes of light per second

Answer 14

e. the ability to distinguish ultraviolet radiation and 300 flashes of light per second

Question 15

When light first enters the human eye, the first structure that it must pass through is the _____.

a. pupil
b. cornea
c. aqueous humor
d. lens
e. vitreous humor

Answer 15

b. cornea

Question 16

Rods and cones are similar in that they both _____.

a. release glutamate as the primary neurotransmitter
b. use photopsins as the visual pigments in both rods and cones
c. depolarize when exposed to light
d. fire action potentials when exposed to light
e. respond to all wavelengths of light

Answer 16

a. release glutamate as the primary neurotransmitter

Question 17

The sense described as umami is one of _____.

a. savory and delicious sensation on the tongue
b. incoming nutrients at the level of the small intestine
c. flavors of oak barrels in wine
d. a burning sensation associated with chili peppers
e. olfactory essence of chocolate

Answer 17

a. savory and delicious sensation on the tongue

Question 18

Myosin heads have binding sites for _____.

a. tropomyosin and troponin
b. ATP and actin
c. tropomyosin and actin
d. actin and calcium
e. ATP and calcium

Answer 18

b. ATP and actin

Question 19

Among these choices, the most energy-efficient form of animal movement, per kg of body mass, is _____.

a. large flying birds
b. small birds flying
c. swimming by small fish
d. swimming by large fish
e. small running mammals

Answer 19

d. swimming by large fish

Question 20

Which of the following sensory receptors is incorrectly paired with its category?

a. hair cell: mechanoreceptor
b. snake pit organ: thermoreceptor
c. taste receptor: chemoreceptor
d. olfactory receptor: electromagnetic receptor

Answer 20

d. olfactory receptor: electromagnetic receptor

Question 21

The middle ear converts

a. pressure waves to hair cell movements.
b. fluid pressure waves to nerve impulses.
c. fluid pressure waves to air pressure waves.
d. air pressure waves to nerve impulses.
e. air pressure waves to fluid pressure waves.

Answer 21

e. air pressure waves to fluid pressure waves.

Question 22

During the contraction of a vertebrate skeletal muscle fiber, calcium ions

a. break cross-bridges as a cofactor in hydrolysis of ATP.
b. transmit action potentials from the motor neuron to the muscle fiber.
c. spread action potentials through the T tubules.
d. bind with troponin, changing its shape so that the myosin-binding sites on actin are exposed.

Answer 22

d. bind with troponin, changing its shape so that the myosin-binding sites on actin are exposed.

Question 23

Which sensory distinction is not encoded by a difference in neuron identity?

a. red and green
b. salty and sweet
c. loud and faint
d. white and red
e. spicy and cool

Answer 23

c. loud and faint

Question 24

The transduction of sound waves into action potentials occurs

a. within the middle ear as the vibrations are amplified by the malleus, incus, and stapes.
b. as the basilar membrane vibrates at different frequencies in response to the varying volume of sounds.
c. when hair cells are bent against the tectorial membrane, causing them to depolarize and release neurotransmitter that stimulates sensory neurons.
d. in the tectorial membrane as it is stimulated by hair cells.

Answer 24

c. when hair cells are bent against the tectorial membrane, causing them to depolarize and release neurotransmitter that stimulates sensory neurons.

Question 25

Although some sharks close their eyes just before they bite, their bites are on target. Researchers have noted that sharks often misdirect their bites at metal objects and that they can find batteries buried under sand. This evidence suggests that sharks keep track of their prey during the split second before they bite in the same way that

a. a rattlesnake finds a mouse in its burrow.
b. a platypus locates its prey in a muddy river.
c. an insect avoids being stepped on.
d. a star-nosed mole locates its prey in tunnels.

Answer 25

b. a platypus locates its prey in a muddy river.

Question 26

Sensory pathways have four basic functions: sensory reception, transduction, transmission, and perception. How do these functions differ between yourself and a star-nosed mole?
Select all that apply.
a. The mechanism by which the energy of a sensory stimulus is transduced into a receptor potential differs between humans and star-nosed moles.
b. The perception of sensory input by humans and star-nosed moles differs.
c. The number and type of sensory receptors in humans and star-nosed moles differ.

Answer 26

b. The perception of sensory input by humans and star-nosed moles differs.
c. The number and type of sensory receptors in humans and star-nosed moles differ.

Question 27

Identify the correct statement(s) about sensory receptors.
Select all that apply.
a. Foods taste spicy when they activate the same sensory receptors that high temperatures activate.
b. Mechanoreceptors detect sound.
c. Electromagnetic receptors detect pheromones.

Answer 27

a. Foods taste spicy when they activate the same sensory receptors that high temperatures activate.
b. Mechanoreceptors detect sound.

Question 28

In mammals, the eardrum transmits sound waves to three small bones, which transmit the waves to fluid waves within the cochlea. Where are the three small bones located?

a. Inner ear
b. Outer ear
c. Middle ear

Answer 28

c. Middle ear

Question 29

Identify the role(s) of ATP in muscle contraction.
Select all that apply.
a. Binds to the troponin complex to expose myosin-binding sites
b. Binds to myosin to break an actin-myosin cross-bridge
c. Provides the energy to convert myosin to a form that forms a cross-bridge with actin

Answer 29

b. Binds to myosin to break an actin-myosin cross-bridge

c. Provides the energy to convert myosin to a form that forms a cross-bridge with actin

Question 30

Plasma membranes of adjacent cardiac muscle cells interlock at specialized regions called intercalated disks. What is the significance of this feature of cardiac muscles?

a. The intercalated disks allow coordinated contraction of the whole heart.
b. The intercalated disks play the same role as striations of skeletal muscle.
c. The intercalated disks generate action potentials within the heart muscle without nervous system input.

Answer 30

a. The intercalated disks allow coordinated contraction of the whole heart.

Question 31

What is true of taste receptors?

a. There are four main types of taste receptor.
b. The different types of taste receptor are limited, each to its specialized region of the tongue.
c. A taste bud consists of at least one sensory receptor cell from each of the major types of taste receptors.
d. Taste buds consist of sensory cells that act as mechanoreceptors.
e. More than one of these is true.

Answer 31

c. A taste bud consists of at least one sensory receptor cell from each of the major types of taste receptors.

Question 32

What is the proper order of these structures, from most inclusive to least inclusive?

1. inner ear
2. tectorial membrane 3. organ of Corti
3. cochlea
   a. 4, 1, 3, 2
   b. 1, 4, 3, 2
   c. 4, 1, 2, 3
   d. 1, 4, 2, 3
   e. 4, 2, 1, 3

Answer 32

b. 1, 4, 3, 2

Question 33

Which sensory cells are common to the senses of hearing and equilibrium in humans?

a. otolithocytes
b. vestibular cells
c. ocelli
d. tectorial cells
e. hair cells

Answer 33

e. hair cells

Question 34

In vertebrate eyes, the conversion of light energy to chemical energy occurs most directly as the result of changes to

a. opsin.
b. transducin.
c. retinal.
d. phosphodiesterase.
e. cyclic GMP (cGMP).

Answer 34

c. retinal.

Question 35

An example of a ball-and-socket joint is found at the junction of the

a. femur with the pelvic girdle.
b. humerus with the radius and ulna.
c. femur with the tibia and fibula.
d. adjacent phalanges.

Answer 35

a. femur with the pelvic girdle.

Question 36

Which of the following is not a function of the lateral line system in fish?

a. monitoring water currents
b. sensing low-frequency sounds
c. detecting vibrations from nearby prey
d. sensing light in the water

Answer 36

d. sensing light in the water

Question 37

Which of the following is not a type of sensory receptor?

a. mechanoreceptor
b. chemoreceptor
c. electromagnetic receptor
d. thermoreceptor
e. none of the above

Answer 37

e. none of the above

Question 38

The function of the basilar membrane is to

a. transmit vibrations from the tympanic membrane to the oval window.
b. vibrate up and down in response to the fluid pressure waves in the vestibular canal.
c. vibrate in response to moving air reaching the outer ear.
d. create pressure waves in the perilymph (fluid inside the cochlea).

Answer 38

b. vibrate up and down in response to the fluid pressure waves in the vestibular canal.

Question 39

Which of the following statements about the compound eyes of insects, crustaceans, and some polychaete worms is incorrect?

a. They consist of several thousand light detectors called ommatidia.
b. They are effective at detecting movement.
c. They offer a very wide field of view.
d. They are essential for avoiding predators.
e. They contain retinas.

Answer 39

e. They contain retinas.

Question 40

Which of the following elements of the sliding-filament model of muscle contraction is incorrectly defined?

a. tropomyosin—a regulatory protein
b. troponin complex—a set of additional regulatory proteins
c. transverse tubules—infoldings of the plasma membrane
d. sarcoplasmic reticulum—a specialized endoplasmic reticulum
e. calcium ions—ions bound to the myosin protein that play a role in muscle contraction and relaxation

Answer 40

e. calcium ions—ions bound to the myosin protein that play a role in muscle contraction and relaxation

Question 41

What could explain the higher energy cost of flying compared with that of swimming?

a. Energy cost is less important to flying animals than to swimming animals. Because of this, there has not been much natural selection for lower energy cost in flying animals.
b. Flying animals use more energy to overcome gravity than do swimming animals.
c. Smaller animals have higher energy costs than larger ones, and flying animals are smaller than swimming animals.
d. Friction is more of a problem for flying animals than for swimming animals.

Answer 41

b. Flying animals use more energy to overcome gravity than do swimming animals.

Question 42

Contraction of myofibrils in skeletal muscle is initiated by

a. the uptake of calcium by the sarcoplasmic reticulum.
b. the release of calcium from the sarcoplasmic reticulum.
c. the uptake of calcium by the transverse (T) tubules.
d. the release of calcium from the transverse (T) tubules.
e. the release of calcium from the mitochondria.

Answer 42

b. the release of calcium from the sarcoplasmic reticulum.

Question 43

Which of the following is characteristic of slow-twitch muscle fibers?

a. large numbers of mitochondria
b. easily fatigued
c. low myoglobin content
d. fast contraction speed
e. largely anaerobic respiration

Answer 43

a. large numbers of mitochondria

Question 44

The precision of a motor unit is inversely proportional to its size, meaning that small motor units exercise greater precision than large ones; therefore,

a. eye muscles might have 1,000 fibers in each unit, while thigh muscles might only have 10.
b. thigh muscles and eye muscles might have the same number of muscles fibers.
c. thigh muscles might have 1,000 fibers in each unit, while eye muscles might only have 10.

Answer 44

c. thigh muscles might have 1,000 fibers in each unit, while eye muscles might only have 10.