Sensory & Motor Systems Mb, Biol 1620

Front 1

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

Back 1

Sensory transduction (The conversion of sensory energy to a change in membrane potential is sensory transduction.)

Front 2

Sensory adaptation is apparent when _____.

Back 2

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

(ensory adaptation is a decrease in responsiveness during continued stimulation.)

Front 3

The correct sequence of sensory processing is _____.

Back 3

stimulus reception → sensory transduction → sensory perception sensory adaptation

Front 4

Stimuli alter the activity of excitable sensory cells and generate action potentials via _____.

Back 4

transduction

Front 5

Which type of receptor would you expect to be most abundant in the antennae of a moth?

Back 5

chemoreceptors

Front 6

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

Back 6

mechanosensory stimuli

(Different frequencies of pressure waves in the cochlea cause certain places along the basilar membrane to vibrate, mechanically bending particular hair cells to initiate sensory transduction.)

Front 7

The middle ear converts _____.

Back 7

air pressure waves to fluid pressure waves

Front 8

During an auditory transduction, ion flow varies across the _____.

Back 8

hair cell membrane

Front 9

The _____ is the region of the eye where photoreceptors are most highly concentrated.

Back 9

fovea

(Photoreceptors are most highly concentrated in the region of the retina known as the fovea.)

Front 10

What name is given to the tough layer that forms the "white" of the eye?

Back 10

sclera

(The sclera is the tough outer layer that forms the white of the eye.)

Front 11

The _____ changes shape to focus light on the retina.

Back 11

lens

(By changing the shape of the lens the eye can bend light rays such that they focus on the retina.)

Front 12

What name is given to the opening that allows light into the interior of the eye?

Back 12

pupil

(The pupil is the opening in the iris that lets light into the interior of the eye.)

Front 13

A person able to hear only high-frequency sounds would probably have which of the following structural problems in the ear?

1.The basilar membrane is stiffened along its entire length.

2.The ear ossicles are abnormally thickened.

3.The tympanum is damaged because of chronic ear infections.

3.All of these problems could result in inability to detect low-frequency sound.

Back 13

1.The basilar membrane is stiffened along its entire length.

Front 14

The cochlea _____.
I) amplifies sound vibrations
II) collects sound pressure waves
III) detects the frequency of sounds

Back 14

only II and III

Front 15

Hair cells in the vertebrate ear are responsible for transducing sound pressure waves. Ion channels in the hair cell membrane open when _____.

Back 15

The membrane is distorted mechanically

Front 16

Rods and cones are similar in that they both _____.

Back 16

release glutamate as the primary neurotransmitter

(Both rods and cones use glutamate as the neurotransmitter.)

Front 17

Rods exposed to light will _____.

Back 17

hyperpolarize due to the closing of sodium channels

Front 18

The sense described as umami is one of _____.

Back 18

savory and delicious sensation on the tongue

(Umami is a Japanese term that describes "savory and delicious" tastes.)

Front 19

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

Back 19

olfactory bulb

Front 20

Two students studying physiology taste a known "bitter" substance, and both report sensing bitterness. They then sample another substance. Student A reports sensing both a bitter taste and a salty taste, but student B reports only a salty taste. What is the most logical explanation?

Back 20

Student A has a protein receptor capable of detecting a bitter molecule found in that substance, whereas student B lacks that particular protein receptor.

Front 21

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

muscle spindle – electromagnetic receptor

taste receptor – mechanoreceptor

hair cell – mechanoreceptor

rod – chemoreceptor

Back 21

hair cell – mechanoreceptor

Front 22

During the course of muscle contraction the potential energy stored in ATP is transferred to potential energy stored in _____.

Back 22

the myosin head

(The hydrolysis of ATP causes the myosin head to change position, storing energy that will be used to contract the muscle.)

Front 23

The release of _____ ions from the sarcoplasmic reticulum is required for skeletal muscle contraction.

Back 23

calcium

(Calcium ions interact with proteins on the thin filament, resulting in the exposure of the myosin-binding sites on the actin.)

Front 24

Myosin heads bind to _____, which they then pull and cause to slide toward the center of the sarcomere.

Back 24

thin filaments

(Myosin heads bind to thin filaments, release their bound ADP and phosphate, and bend, sliding the thin filaments toward the center of the sarcomere.)

Front 25

Of these events, the first to occur when a motor neuron stops sending an impulse to a muscle is _____.

Back 25

he pumping of calcium ions out of the cytoplasm and back into the sarcoplasmic reticulum

(This is the first of the events that ultimately result in the relaxation of a muscle.)

Front 26

The thick filaments of sarcomeres are composed of _____.

Back 26

myosin

Front 27

The thin filaments of sarcomeres are composed of _____.

Back 27

actin

Front 28

A single muscle cell is referred to as a _____.

Back 28

muscle fiber

Front 29

Which muscle type is involved in the function of the digestive tract and blood vessels?

A.Smooth.

B.Cardiac.

C.Skeletal.

D.Voluntary.

Back 29

A.Smooth.

Front 30

How does cardiac muscle differ from the other types of muscle?

Back 30

It contains branched cells.

Front 31

True or false? Myofibrils are the alternating light-dark units that produce the banded appearance of muscle fibers.

Back 31

False

Sarcomeres are the alternating light-dark units that produce the banded appearance of myofibrils, which are the strands that make up each muscle fiber.

Front 32

Which molecules form the thick filaments of sarcomeres?

Back 32

Myosin

Front 33

Which of the following interactions is the molecular basis of muscle contraction?

Back 33

Myosin and thin filaments.

(The interaction of myosin and thin filaments (actin) is the molecular basis of muscle contraction.)

Front 34

Which step constitutes the power stroke of muscle contraction?

Back 34

The phosphate ion is released, and the myosin head moves back to its original position.

(

The power stroke occurs when the myosin head pivots, causing the actin filament to slide past the myosin filaments.

)

Front 35

Which of the following statements about the stimulation of muscle cells is true?

Back 35

An action potential in a muscle cell ultimately results in the release of calcium ions into the cell.

(

An action potential causes T tubules to depolarize, which stimulates the sarcoplasmic reticulum to release calcium ions into the muscle cell.

)

Front 36

Myosin heads have binding sites for _____.

Back 36

ATP and actin

Front 37

The contraction of skeletal muscles is based on _____.

Back 37

myosin cross-bridges binding to actin and transitioning from a high-energy to a low-energy state

Front 38

A skeletal muscle deprived of adequate ATP supplies will _____.

Back 38

enter a state where actin and myosin are unable to separate

Front 39

The "motor unit" in vertebrate skeletal muscle refers to _____.

Back 39

one motor neuron and all of the muscle fibers on which it has synapses

Front 40

What would happen to people exposed to a chemical warfare agent that blocked acetylcholine from binding to muscle receptors?

Back 40

Muscle contractions would be prevented, causing paralysis.

Front 41

When an action potential from a motor neuron arrives at the neuromuscular junction (NMJ), a series of events occurs that leads to muscle contraction. Which of the following events will occur last (that is, after all of the others)?

Back 41

conformational change in troponin

Front 42

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

Back 42

using peristaltic contractions of its circular and longitudinal muscles

Front 43

Identify the correct statement(s) about sensory receptors.

1.Foods taste spicy when they activate the same sensory receptors that high temperatures activate.

2.Electromagnetic receptors detect pheromones.

3.Mechanoreceptors detect sound.

Back 43

1 & 3

Mechanoreceptors sense physical deformation caused by forms of mechanical energy such as pressure, touch, stretch, motion, and sound. Pheromones are detected by very sensitive chemoreceptors with great specificity. Electromagnetic receptors detect various forms of electromagnetic energy, such as visible light, electricity, and magnetism. The hot spicy taste of jalapeno pepper activates thermoreceptors that also respond to temperatures of 42°C and above. Menthol, a cool plant product, activates thermoreceptors that also respond to temperatures of 28°C and below. Read about mechanoreceptors, chemoreceptors, electromagnetic receptors, and thermoreceptors.

Front 44

Identify the role(s) of ATP in muscle contraction.

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

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

3.Binds to the troponin complex to expose myosin-binding sites

Back 44

1 & 2

Read about the sliding-filament model of muscle contraction and the roles that ATP plays in muscle contraction.