Physiology Exam #3

Release of acetylcholine at the neuromuscular junction typically results in... a. opening of chemically-gated sodium channels. b. opening of voltage-gated sodium channels. c. release of calcium ions (Ca2+) from the sarcoplasmic reticulum. d. All of the above are likely.

All of the above are likely

Alternating the contraction of different groups of muscle fibers helps a muscle sustain contraction and avoid fatigue. This strategy is called... a. Asynchronous recruitment b. synchronous recruitment c. complex recruitment d. simple recruitment

Asynchronous recruitment

Bob fell off a ladder trying to clean out his gutters. His wife rushed him to the emergency room. The doctor tested his knee-jerk reflex and found it was normal. These results suggest that? a. Bob has no damage to his spinal cord. b. bob is stupid c. Bob has damage to his spinal cord.

Bob has no damage to his spinal cord.

Which of the following is NOT required prior to skeletal muscle fiber contraction? a. Ca++ must enter the muscle fiber from the extracellular fluid b. cross-bridge formation and contraction requires the presence of calcium (Ca ++) inside the muscle cell. c. linear arranged within myofibrils, shorten as myosin heads pull on the actin filaments. d. Ca++ must leave the muscle fiber from the extracellular fluid

Ca++ must enter the muscle fiber from the extracellular fluid

Ca++ entering the cell from the extracellular fluid is required for contractile skeletal muscle cells to contract. T/F

False

Skeletal muscle contraction starts when the muscle fiber depolarizes due to the release of calcium into the cytoplasm. True False

False

Smooth muscle is under voluntary control. True False

False

The muscle twitch (i.e. the contraction-relaxation cycle) is much faster than an action potential. T/F

False

______ control allows the body to anticipate a stimulus and begin a movement, whereas ____ feedback will generally result in the cessation of that movement. a. feedforward; positive b. feed-backward; negative c. Feedforward; negative d. feed-backward; positive

Feedforward; negative

Increasing muscle mass thru exercise is primarily due to... a. increasing the thickness of existing muscle fibers. b. increasing the number of muscle fibers. c. adding more motor units.

Increasing the thickness of existing muscle fibers.

Match each part to its function: iris rhodopsin tectorial membrane cristae in ampullae otoliths in maculae sense rotational movement a. light receptor b. controls diameter of pupil c. sense lateral movement d. stimulates hair cells

Iris: controls diameter of pupil rhodopsin: light receptor tectorial membrane: stimulates hair cells cristae in ampullae: sense rotational movement otoliths in maculae: sense lateral movement

If a drug inhibits acetylcholinesterase activity in the neuromuscular junction, what effect does the drug have on the membrane potential of the muscle fiber? a. it wouldn't depolarize b. It would remain depolarized c. it would remain polar d. it has no effect

It would remain depolarized

If you floating in outer space experiencing zero gravity, the weightlessness would cause the otoliths in your macula to lose their reference point. Which of these sensations might you expect to have difficulty perceiving? a. Linear acceleration b. vertical acceleration c. curved acceleration d. horizontal acceleration

Linear acceleration

The primary sensory neurons in your retina are depolarized, the concentration of cyclicGMP in your rods is high, and cyclic-nucleotide gated channels are open. It is likely.. a. day time. b. night time.

Night time

Which of the below is NOT a characteristic of olfaction that we discussed in class? a. Olfaction is one of the 3 senses contributing to our sense of equilibrium b. Olfaction is responsible for stimuli c. The olfactory receptor cells are bipolar d. system consists of the nose and the nasal cavities, which in their upper parts support the olfactory

Olfaction is one of the 3 senses contributing to our sense of equilibrium

Which of these is NOT a characteristic of olfaction? a. Neurons from the olfactory bulb interact with the amygdala and hippocampus. b. Olfactory neurons die and are replaced by new neurons roughly every 2 months. c. Olfaction is one of the three senses contributing to our sense of equilibrium. d. The olfactory tracts do not directly relay to the CNS via the thalamus.

Olfaction is one of the three senses contributing to our sense of equilibrium.

You work at the Tabasco factory in Louisiana. You spend your workday blending barrels of fermented chili peppers with vinegar and bottling hot sauce. The smells do not bother you, because... a. Olfactory receptors are tonic, they adapt slowly to constant stimulus. b. Olfactory receptors are tonic, they quickly adapt to constant stimulus. c. Olfactory receptors are phasic, they quickly adapt to constant stimulus. d. Olfactory receptors are phasic, they adapt slowly to constant stimulus.

Olfactory receptors are phasic, they quickly adapt to constant stimulus.

Stretching a muscle spindle causes... a. extension of that muscle b. reflex compression of that muscle c.Reflex contraction of that muscle

Reflex contraction of that muscle

During crossbridge cycling, the binding of ATP to the myosin head... a. separates the myosin head from actin b. obsorbes the myosin head from actin c. Releases the myosin head from actin

Releases the myosin head from actin

In skeletal muscle cells, incoming electrical signals travel through the... a. sarcoplasmic reticulum b. T-tubules c. mitochondria

T-tubules

The inner ear houses two fluid filled structures. Which of these is critical to equilibrium? a. the cochlea b. the semicircular canals

The semicircular canals

Which is true about tonic receptors? a. They adapt slowly to constant stimulus b. they cannot adapt to stimulus c. they can adapt to stimulus d. they adapt rapidly to a single stimuli

They adapt slowly to constant stimulus

What is TRUE about the proteins troponin and tropomyosin in skeletal muscle contraction? a. they don't inhibit bindings necessary for contraction b. They inhibit the bindings necessary for contraction c. they inhibit the binding necessary for movement d. non of the above

They inhibit the bindings necessary for contraction

Why do you think the taste receptor cells in a taste bud are joined by tight junctions? a. to separate chemicals flowing out of the taste pore to the taste receptor cells b. to combine the chemicals flowing in the taste pore with the taste receptors c. To force dissolved chemicals flowing into a taste pore to interact with the taste receptor cells.

To force dissolved chemicals flowing into a taste pore to interact with the taste receptor cells.

Which about smooth muscle contraction is FALSE? a. Smooth muscle uses actin-myosin cross-bridges to create force. b. Contraction can occur without a change in membrane potential. c. Troponin plays the same role as in skeletal muscle. d. Ca2+ initiates the contraction.

Troponin plays the same role as in skeletal muscle.

An olympic sprinter will tend to have more thicker muscle fibers relying on glycolytic metabolism. True False

True

Motor neurons typically control multiple muscles cells. T/F

True

Reflex arcs are an exception to the rule that skeletal muscle is always under voluntary control. True False

True

taste receptor cells are NOT neurons. T/F

True

Compared to skeletal muscle, contraction of smooth muscle cells is... a. a slower response to stimulus; sustained without fatigue b. a faster response to stimulus; sustained without fatigue c. a slower response to stimulus; sustained with fatigue d. a faster response to stimulus; sustained with fatigue

a slower response to stimulus; sustained without fatigue

The calcium pumps (Ca2+ ATPase) in the sarcoplasmic reticulum are examples of... a. facilitated diffusion b. osmosis c. active transport d. simple diffusion

active transport

What features are shared (or similar) between hearing and vision? a. pathways from paired sensory organs diverge and cross over on the way to the CNS b. information is relayed thru the thalamus c. they both involve some type of tonic receptor d. all of the above

all of the above

The primary purpose of the middle ear bony structures (maleus, incus and stapes) is to... a. equalize pressure in the middle ear. b. amplify the vibration as it conducts to the cochlea. c. dampen the vibration as it conducts to the cochlea. d. transduce the sound waves into electrical signals.

amplify the vibration as it conducts to the cochlea.

Which of these is most likely an example of top-down processing in the visual system? a. focusing attention on a bright light b. detecting outlines of objects c. recognizing colors d. an optical illusion

an optical illusion

After an injury, Jodie has difficulty recognizing and interpreting certain sounds. These symptoms imply damage to the... a. frontal cortex b. peripheral cortex c. auditory cortex

auditory cortex

During voluntary movement, you change your body posture.... a. only based on feedback after you move. b. only using anticipatory feedforward signals before you move. c. before you move in anticipation of the movement AND after initiating the movement to compensate or correct your body's position.

before you move in anticipation of the movement AND after initiating the movement to compensate or correct your body's position.

in a healthy individual, where would you NOT expect to find significant amounts of creatine kinase? a. cells b. blood c. liver d. intestines

blood

The sarcolemma of a muscle fiber serves the same function as the _____ in other cells: a. cytoplasm b. neuron pathway c. cell membrane d. blood

cell membrane

Sucrose solution sensory receptor type a. thermoreceptor b. nicotinic c. photoreceptor d. chemoreceptor

chemoreceptor

The way the rods of the eye communicate with their secondary neurons is an example of... a. divergence b. convergence c. insurgence

convergence

ou step on a lego with your bare foot, the flexor muscles of your injured limb contract and lift while the effectors of your other leg brace and keep you upright. This is an example of the... a. crossed-intenser reflex b. leveled-extensor reflex c. crossed-extensor reflex. d. leveled-intenser reflex

crossed-extensor reflex

If glutamate is normally an excitatory neurotransmitter, why are some bipolar cells turned ON by light and some OFF by light? a. same receptors b. Different receptors c. stronger receptors c. shorter receptors

different receptors

A person with defective rods will have trouble... a. distinguishing shapes at the periphery of the visual field; seeing well in the dark b. distinguishing shapes at the periphery of the visual field; seeing well in the light c. distinguishing how far something is at the periphery of the visual field; seeing well in the dark

distinguishing shapes at the periphery of the visual field; seeing well in the dark

Which is the correct order of organization of a skeletal muscle from superficial to deep? a. fascicle; epimysium; whole muscle; perimysium b. whole muscle, epimysium, fascicle, perimysium c. epimysium; whole muscle; perimysium; fascicle d. perimysium, whole muscle, epimysium, fascicle

epimysium; whole muscle; perimysium; fascicle

The lens bends light and focuses it onto the... a. sclera b. optic disk c. fovea d. occipital lobe

fovea

As a protective mechanism, stretching a skeletal muscle fiber causes sensory neurons (i.e. proprioceptors) to ______ their rate of firing. a. stop b. decrease c. Stretching the muscle fiber does not affect sensory neurons. d. increase

increase

A decrease in the release of neurotransmitter from the photoreceptor would indicate an... a. increase in vision inducing blindness b. increase in light intensity c. decrease in light intensity

increase in light intensity

A contraction that generates enough force to move a load is known as _____, whereas one that generates force that equals the load is known as ____. a. isometric; isotonic b. isotonic; isometric c. neither is correct

isotonic; isometric

Which is true for a somatic motor neuron action potential but not a skeletal muscle fiber action potential? a. leads to absorption of ACh b. they travel faster than skelital muscle fiber action potential c. leads to release of oxytocin d. Leads to release of ACh

leads to release of ACh

In the human eye, if the ______ focuses the light anywhere but the ______ then vision is imperfect. a. pupil, scelera b. lens, fovea c. pupil, fovea d. lens, scelera

lens, fovea

Which are characteristics of slow-twitch oxidative skeletal muscle fibers? a. Long contraction duration AND many mitochondria b. short contraction duration AND very little mitochondria c. average contraction duration AND many mitochondria d. short contraction duration AND many mitochondria

long contraction duration AND many mitochondria

Muscle tension sensory receptor type a. photoreceptor b. mechanoreceptor c. chemoreceptor d. nicotinic

mechanoreceptor

Osmolality sensory receptor type a. mechanoreceptor b. nicotinic c. chemoreceptor d. photoreceptor

nicotinic

Which is a potential energy source for an athlete sprinting the 40-yard dash? a. phosphocreatine b. creatine kinase c. None of the other options are likely. d. ryanodine receptors e. myoglobin

phosphocreatine

The sensory system does all of the following EXCEPT... a. projects nerves and signals to effect change in target muscles b. encode information from the environment c. relay information about the environment to the CNS d. detect change in the environment

projects nerves and signals to effect change in target muscles

Which phases of a muscle twitch require ATP? a. Relaxation and contraction period b. latent and contraction period c. relaxation and latent period

relaxation and contraction period

The structural elements responsible for the striated appearance of skeletal muscle are called... a. myosin b. actin c. sarcomeres d. tropomyosin

sarcomeres

Sweet, bitter, and umami signals are communicated through a G-protein coupled ______ which can amplify the signal sent to the primary sensory neuron. a. first-messenger system b. Second-messenger system c. third-messenger system

second-messenger system

A person with defective rods will have trouble... Choose all that apply a. focusing on close objects. b. seeing well in the dark. c. distinguishing colors. d. distinguishing shapes at the periphery of the visual field.

seeing well in the dark and distinguishing shapes at the periphery of the visual field

Why is the eye (iris) pigmented and why does eye color vary among humans? a. sexual selection; iris pigment blocks and/or absorbs excess light from the retina; dual variation in the amount and type of melanin deposited in the iris muscles b. natural selection; iris pigment lets in and/or absorbs excess light from the retina; individual variation in the amount and type of melanin deposited in the iris muscles c. sexual selection; iris pigment blocks and/or absorbs excess light from the retina; individual variation in the amount and type of melanin deposited in the iris muscles d. evolution; iris pigment blocks and/or absorbs excess light from the retina; individual variation in the amount and type of melanin deposited in the iris muscles

sexual selection; iris pigment blocks and/or absorbs excess light from the retina; individual variation in the amount and type of melanin deposited in the iris muscles

What type of receptors are the hair cells that bend to open ion channels in the cochlea? a, Simple, mechanoreceptors b. difficult, chemoreceptors c. simple, photoreceptors d. none of the above

simple, mechanoreceptors

The neurons of the special senses each carry info to cortexes in the brain that are specific to each sense. However, general sensation info is all carries to the... a. temporal b. Somatosensory cortex c. cerebral cortex d. pre-frontal cortex

somatosensory cortex

In skeletal muscle, after neurotransmitters bind to their receptors the chemically-gated Na+ channels open. What happens next? a. the closing of voltage-gated Na+ channels b. The opening of voltage-gated Na+ channels c. removal of voltage-gated Na+ channels d. none of the above

the opening of voltage-gated Na+channels

A blind spot in the retina occurs where... a. the fovea is located. b. photoreceptors synapse with bipolar cells. c. the optic nerve leaves the eye. d. bipolar cells synapse with ganglion cells.

the optic nerve leaves the eye

In smooth muscle, the Ca2+ necessary for contraction can come from... a. sarcoplasmic reticulum b. intracellular fluid c. extracellular fluid d. a and c f. a and b

the sarcoplasmic reticulum; the extracellular fluid

Most reflex movements are integrated by... a. the nervous system b. the brain stem c. the spinal cord d. muscle contractions

the spinal cord

Why does rigor mortis occur after death? (choose all that apply) a. Body temperature decreases significantly. b. There is no ATP available to bind to myosin. c. Connective tissue around the muscle fascicles hardens. d. Myosin is tightly bound to actin.

there is no ATP available ton bind to myosin, myosin is tightly bound to actin

Temperature sensory receptor type a. thermoreceptor b. mechanoreceptor c. photoreceptor

thermoreceptor