ch 9 anatomy

78. Acetylcholine released by the myofibril crosses the synaptic cleft to bind to the motor neuron ending.

false

This figure shows a pair of relaxed sarcomeres. Use the labels to indicate the various features of the striations of these sarcomeres. Labels may be use more than once. the bottoms

sarcomere

In a recording of a muscle twitch, the delay between the time a stimulus is applied and the time the muscle responds is called the Multiple Choice -latent period. -refractory period. -contraction period. -relaxation period.

latent period

The point of communication between a motor neuron and a muscle fiber is called a

synapse

. Acetylcholine (ACh) is released from motor neurons and enters the __________. multiple choice -axon terminal -sarcomere -synaptic cleft - transverse tubules

synaptic cleft

These chemicals diffuse across a small gap between the neuron and muscle fiber called the

synaptic cleft

If little or no oxygen is available, pyruvic acid is converted to ---. If, however, oxygen is available, the pyruvic acid molecules enter the aerobic respiration pathways.

lactic acid

57. The buccinator muscle is in the A. buttocks. B. chest. C. bladder. D. cheek.

D

60. The linea alba is A. a muscle extending from the ischial spine to the coccyx and sacrum. B. a curved, broad muscle on the side of the chest. C. a muscle beneath the skull. D. a band of tough connective tissue to which abdominal wall muscles attach.

D

62. Which of the following is not a muscle of mastication? A. Medial and lateral pterygoid B. Masseter C. Temporalis D. Zygomaticus

D

68. Muscle atrophy that progresses with aging is caused by reduction in A. ATP. B. myoglobin. C. the sizes of muscle fibers. D. all of the above.

D

7. The discoloration and swelling of a muscle strain is due to A. excess myofibrils. B. separated tendons. C. severed nerves. D. ruptured blood vessels.

D

73. Temporomandibular joint (TMJ) syndrome causes A. headache. B. ringing in the ears. C. clicking sound from the jaw. D. all of the above.

D

Drag and drop each of the descriptions in the appropriate box, matching them with the correct skeletal muscle fiber type. slow-twitch

-fatigue resistant -oxidative -many mitochondria -extensive capillary networks -used in low intensity exercise all but 3

Place the steps of muscle relaxation in the proper sequence Nerve impulses no longer arrive at neuromuscular junction. a,aa,c,t,m

-Acetylcholine is no longer released -Acetylcholinesterase break down Ach, and the muscle fiber is no longer stimulated -Calcium ions are actively transported from sarcoplasm into the sarcoplasmic reticulum -Troponin and tropomyosin shift, blocking further interaction between myosin and actin -muscle fiber relaxes

Place the steps of muscle fiber contraction in the correct sequence. A nerve impulse arrives at the distal end of a motor neuron axon. Ach binds to receptors on the motor end plate

2

This figure shows a pair of relaxed sarcomeres. Use the labels to indicate the various features of the striations of these sarcomeres. Labels may be use more than once -`A band

2 very top

70. Myasthenia gravis is A. an autoimmune disorder. B. a bacterial infection. C. a form of cancer. D. the result of injury.

A

28. A shift in metabolism that breaks down pyruvic acid to lactic acid is called A. aerobic threshold. B. lactic acid threshold. C. pyruvic acid threshold. D. glycogenic threshold.

B

30. When ATP levels are low, the relationship between ATP and creatine phosphate is that A. ATP supplies energy to synthesize creatine phosphate from creatine and phosphate. B. creatine phosphate supplies energy to regenerate ATP from ADP and phosphate. C. both have three phosphate groups. D. both are required to stimulate a muscle to contract.

B

43. Activities such as distance swimming and distance running are most likely to stimulate development of A. slow fatigable muscle fibers. B. fast fatigable muscle fibers. C. slow fatigue-resistant fibers. D. fast fatigue-resistant fibers.

C

Identify each of the following regions of a sarcomere. red and green

I band

When myosin heads form cross-bridges during muscle contractions, they bind to binding sites found on _________ , a component of thin filaments. Multiple Choice -troponin -tropomyosin -calciumactin -actin

actin

The muscle that opposes a particular action is called the Multiple Choice -prime mover. -antagonist. -agonist. -synergist.

antagonist

Cardiac muscle Multiple Choice -excites itself. -is multinucleated. -contains only a few mitochondria. -partially lines the intestines.

excites itself

As exercise continues, the cells now begin to use --- as a fuel to produce ATP. Initially, the anaerobic pathway called---- uses this fuel to produce 2 ATP and 2 molecules of pyruvic acid.

glucose; glycolysis

A gluteal gait, in which a person walks with a waddling limp, is usually caused by a disorder of the Multiple Choice -gluteus medius and gluteus minimus. -gluteus maximus and gluteus medius. -gluteus maximus and gluteus minimus. -gluteus maximus and tensor fasciae latae.

gluteus medius and gluteus minumus

The antidote that holds the most promise to counteract the effects of tubocurarine is one that __________. multiple choice -modifies acetylocholine so that it is unable to bind to acetylcholine receptors -modifies acetylcholine receptors so that they bind acetylcholine stronger than tubocurarine -removes acetylcholine receptors from the end-plate -modifies acetylcholine receptors so that they can no longer bind acetylcholine

modifies acetylcholine receptors so that the bind acetylcholine stronger than tubocurarine

Label the muscle attachments to bone. biceps brachii

muscle

Match the description with the correct component of a muscle fiber. Site for storage of calcium

sarcoplasmic reticulum

For each label, determine whether it describes contraction of smooth muscle or contraction of skeletal muscle. Then place the label in the correct column. contraction only in response to acetylcholine

skeletal muscle

Identify whether the following characteristics describe skeletal, smooth, or cardiac muscle tissue.Labels may be used more than once. single nucleus

smooth and cardiac muscle

For each label, determine whether it describes contraction of smooth muscle or contraction of skeletal muscle. Then place the label in the correct column. Contraction in response to acetylcholine or norepinephrine

smooth muscle

Label the muscle attachments to bone. radius

top arm bone

Label the muscle attachments to bone. coracoid process

very top

Label the parts of a lever system. resistance

weight

Label the features of a neuromuscular junction. motor neuron axon

yellow stick

Label the figure depicting the steps in cellular respiration.

-Glucose -pyruvic acid -lactic acid -citric acid cycle -electron transport cycle -synthesis of 26 ATP

Label the structures found within a skeletal muscle.

-Tendon -fascia -epimysium -perimysium -Fascicle -Endomysium -Muscle fiber -Myofibril -Filaments

Label the skeletal muscle organelles. order of myofibril

-Transverse tubule -Cisternae of sarcoplasmic -sarcoplasmic reticulum

25. The functional connection between a neuron and a skeletal muscle fiber is a A. synapse. B. fascia. C. neuroma. D. dendrite.

A

Identify each of the following regions of a sarcomere. orange

A band

The striations seen in skeletal muscle consist of alternating dark bands, called the __________ bands, and light bands, called the __________ bands.Multiple Choice A; I H; M M; Z I; A

A;I

Tawanda finishes a sprint and suffers great pain in her calf muscles. Her muscle cramps are most likely due to a temporary deficit of Multiple Choice -myosin. -actin. -ATP.

ATP

What is the name of the neurotransmitter used at a skeletal neuromuscular junction? Multiple Choice -Acetylcholinesterase -Acetylcholine -Calmodulin -Norepinephrine

Acetylcholine

What is the first event in muscle fiber contraction? Multiple Choice -The muscle fiber membrane is stimulated and a muscle impulse travels deep into the fiber through transverse tubules. -Calcium ions diffuse from sarcoplasmic reticulum into the sarcoplasm and bind to troponin molecules. -Acetylcholine diffuses across a gap at a neuromuscular junction -.Acetylcholine is released from the end of the motor neuron.

Acetylcholine is released from the end of the motor neuron

Match each description with the correct muscle protein. Location of binding sites for myosin

Actin

27. Arrange the following steps of muscle fiber contraction in the correct sequence. 1. The muscle impulse reaches the sarcoplasmic reticulum and calcium is released. 2. Thin filaments are pulled over the thick filaments. 3. Calcium floods the sarcoplasm and binds to troponin molecules leaving active sites. 4. The impulse arrives at the synapse and travels through the transverse tubules. 5. The muscle fiber shortens and contracts. 6. Myosin heads bind to exposed active sites on actin, forming cross-bridges. A. 6, 3, 1, 4, 2, 5 B. 2, 5, 3, 1, 4, 6 C. 4, 1, 3, 6, 2, 5 D. 3, 5, 2, 1, 6, 4

C

32. A motor unit is A. many myofibrils in a sarcolemma. B. many motor end plates at a neuromuscular junction. C. a motor neuron and the muscle fibers connected to it. D. the functional unit of a muscle fiber.

C

33. During muscle contraction ATP supplies energy for A. creatine phosphate synthesis. B. glycogen synthesis. C. myofilament movement. D. enzyme activity.

C

54. The more movable end of a muscle is its A. origin. B. fulcrum. C. insertion. D. source.

C

65. A gluteal gait, in which a person walks with a waddling limp, is usually caused by a disorder of the A. gluteus maximus and gluteus medius. B. gluteus maximus and gluteus minimus. C. gluteus medius and gluteus minimus. D. gluteus maximus and tensor fasciae latae.

C

What happens to each sarcomere during contraction? multiple choice -Each sarcomere lengthens. -Each sarcomere does not change length. -Each sarcomere shortens.

Each sarcomere shortens

Which muscle group is composed of mainly slow-twitch (type I) fibers? Multiple Choice -Rectus muscles that move the eye -Deltoid muscle of the shoulder -Erector spinae muscles of the back -Small muscles of the hand

Erector spinae muscles of the back

Match the description with the correct component of a muscle fiber. Site of ATP production

Mitochondria

What happens to the H zones in a contracted muscle? multiple choice -The H zones do not change length. -The H zones shorten. -The H zones lengthen.

The H zones shorten

The chemical used at the junction with a skeletal muscle cell is

acetylcholine

As long as oxygen is available, the oxidation of each glucose molecule using --- metabolism will produce, in total, --- ATP molecules.

aerobic,30

80. A broad sheet of dense connective tissue that attaches the coverings of adjacent muscles is called an ______.

aponeurosis

Label the parts of a lever system. Force

arrow

Label the features of a neuromuscular junction. Nucleus of muscle fiber

blue circle

A muscle fiber exposed to a series of stimuli of increasing frequency combines individual twitches (summation) which results in Multiple Choice -complete sustained contraction. -muscle tone. -a latent period. -flaccid muscles.

complete sustained contraction

Therefore, as described, layers of -----enclose and separate the various parts of a skeletal muscle.

connective tissue

Label the parts of a lever system. fulcrum

elbow

76. In the initiation of muscle fiber contraction calcium ions bind to tropomyosin, exposing active sites on actin for cross-bridge formation.

false

This figure shows a pair of relaxed sarcomeres. Use the labels to indicate the various features of the striations of these sarcomeres. Labels may be use more than once I band

in between A band

87. The ______ ______ at the ends of cardiac muscle cells help to join cells.

intercalated discs

84. Muscle fatigue is most likely due to an accumulation of ______ ______.

lactic acid

Zoomed in features of a neuromuscular junction loop lining

motor end plate

A weightlifter uses muscles so the muscles exert more than 75% of their maximum tension. This stimulates Multiple Choice -muscle fibers developing new filaments of actin and myosin. -shrinking of skeletal muscle. -conversion of skeletal to smooth muscle. -an increase in slow, fatigable white fibers.

muscle fibers developing new filaments of actin and myosin

An example of a partial but sustained contraction is Multiple Choice -eye blinking. -a twitch -.muscle tone. -knee jerking.

muscle tone

At what level of organization is a skeletal muscle such as the biceps brachii? Multiple Choice -Cell -Organ -Tissue

organ

Functions of muscles include Multiple Choice -pumping blood. -cushioning tissues from blunt force -.generating electrical impulses. -storage of minerals.

pumping blood

Compared to skeletal muscle, smooth muscle is __________ to contract and __________ to relax. Multiple Choice faster; slower slower; faster slower; slower faster; faster

slower;slower

Identify whether the following characteristics describe skeletal, smooth, or cardiac muscle tissue.Labels may be used more than once. found in walls of hollow organs

smooth muscle

Both acetylcholine and norepinephrine can affect Multiple Choice -skeletal muscle contraction. -synthesis of actin and myosin. -smooth muscle contraction. -exercise tolerance.

smooth muscle contraction

Label the features of a neuromuscular junction. synaptic cleft

space between axon and muscle fiber

Define muscle tone. Multiple Choice -Maximum force generated by a particular muscle -.Single muscle contraction resulting from a single stimulation. -State of partial contraction of muscles while at rest. -Contractions that occur without stimulation of the muscle by a motor neuron.

state of partial contraction of muscles while at rest.

This figure shows a pair of relaxed sarcomeres. Use the labels to indicate the various features of the striations of these sarcomeres. Labels may be use more than once small line

thick filament

In order for a skeletal muscle fiber to contract, calcium must bind to __________ . Multiple Choice -tropomyosin -actin -myosin -troponin

troponin

74. Endomysium separates individual muscle fibers from each other.

true

Label the skeletal muscle organelles. myofibril

tube

This figure shows a pair of relaxed sarcomeres. Use the labels to indicate the various features of the striations of these sarcomeres. Labels may be use more than once H zone.

under A bands

Thin filaments connect to and extend from either side of a __________. These thin filaments are composed largely of the myofilament __________. multiple choice -M line; actin -Z disc; myosin -M line; myosin -z disc; actin

z disc; actin

Label the parts of a lever system. muscle relaxing

bottom muscle

Label the muscle attachments to bone. insertion of biceps brachi

bottom tendon

In order to produce more ATP, the muscle cells next start to use ----, also present in the cytoplasm, to form new ATP. This is done by moving a phosphate and its energy from this molecule to ADP, forming new ATP.

creatine phosphate

Label the skeletal muscle organelles. inside of myofibril

filaments(lines) mitochondria(yellow) sarcolemma(lining)

81. The pigment responsible for the reddish brown color of skeletal muscle is ______.

myoglobin

Place each label on the appropriate filament. purple

myosin, Thich filament

Creatine phosphate Multiple Choice -supplies energy for the synthesis of ATP. -causes the decomposition of ADP -.supplies energy for the breakdown of ATP to ADP. -causes the decomposition of ATP.

supplies energy for the synthesis of ATP

A muscle that assists the agonist is a(n) Multiple Choice -prime mover. -mediator -.antagonist. -synergist.

synergist

88. Muscles that assist an agonist are called ______.

synergists

Label the muscle attachments to bone. tendons of short head of biceps brachii

tendon of longer bicep

Label the muscle attachments to bone. tendon of long head of biceps brachii

tendon of smaller bicep

85. The combining of a series of twitches to produce a more forceful contraction is called ______.

summation

Drag and drop each of the descriptions in the appropriate box, matching them with the correct skeletal muscle fiber type. fast-twitch fibers

-fatigable -Glycolytic -used in forceful exercise

Place the steps of muscle fiber contraction in the correct sequence. A nerve impulse arrives at the distal end of a motor neuron axon. An electrical impulse travels across the sarcolemma and into transverse tubles

3

Place the steps of muscle fiber contraction in the correct sequence. A nerve impulse arrives at the distal end of a motor neuron axon. The impulse causes calcium channels to open in the sarcoplasmic reticulum

4

Place the steps of muscle fiber contraction in the correct sequence. A nerve impulse arrives at the distal end of a motor neuron axon. Calcium ions diffuse out of sarcoplasmic reticulum and bind to tropoinin

5

The amount of oxygen needed to repay the oxygen debt includes the amount of oxygen that muscle cells need to resynthesize ATP. Group starts True or False

True

2. The outermost layer of connective tissue surrounding a skeletal muscle is the A. epimysium. B. perimysium. C. endomysium. D. sarcomysium.

A

20. The toxin that causes botulism A. prevents release of acetylcholine. B. promotes release of acetylcholine. C. decomposes acetylcholine. D. prevents decomposition of acetylcholine.

A

29. Oxygen debt in muscles may develop because of A. the inability of respiratory and circulatory systems to supply enough oxygen to skeletal muscles when used strenuously for a minute or two. B. the inability of myoglobin molecules to store enough oxygen when skeletal muscles are used strenuously for a minute or two. C. too much oxygen used in forming pyruvic acid when skeletal muscles are contracted strenuously for a minute or two. D. too high a concentration of oxygen in the atmosphere.

A

3. Myofibrils are composed primarily of A. actin and myosin. B. perimysium and endomysium. C. troponin and tropomyosin. D. fascia and tendons.

A

The muscle that adducts and flexes the arm is the Multiple Choice -coracobrachialis. -pectoralis minor. -levator scapulae. -teres major.

coracobrachialis

How does an electrical impulse travel into the interior of a muscle fiber? multiple choice -By way of the sarcoplasmic reticulum -Along the endomysium -By the process of diffusion -By way of the transverse tubules

By way of the transverse tubules

As strenuous activity begins, muscle cells first use the -- molecules present in their cytoplasm as their source of energy. The supply of this molecule, however, is limited. It must be produced by other means in order for exercise to continue.

ATP

Myosin heads directly use __________ to transition to their __________ conformation, which enables them ready to bind to actin. multiple choice - 2ATP; non-energized -calcium; non-energized -calcium; energized -ATP; energized

ATP; energized

Zoomed in features of a neuromuscular junction Dot

Acetylcholine molecule

14. Creatine phosphate A. causes the decomposition of ATP. B. causes the decomposition of ADP. C. supplies energy for the synthesis of ATP. D. supplies energy for the breakdown of ATP to ADP.

C

21. Rigor mortis affects skeletal muscles a few hours after death, due to A. an increase in ATP and decreased permeability to calcium. B. a decrease in ATP and increased permeability to calcium. C. an increase in ATP. D. impulses that produce sustained contractions.

B

24. Which of the following statements is correct? A. Tropomyosin molecules move and expose specific sites on myosin filaments. B. Actin filaments slide along myosin filaments. C. Cross-bridges form between actin and the sarcolemma. D. Filaments of troponin and tropomyosin slide past one another.

B

16. Tawanda finishes a sprint and suffers great pain in her calf muscles. Her muscle cramps are most likely due to a temporary deficit of A. actin. B. myosin. C. ATP. D. ADP.

C

31. The characteristic reddish brown color of skeletal muscle comes from which substance? A. Actin B. Myosin C. Myoglobin D. Calcium

C

What are the intercalated discs that are found in cardiac muscle? Multiple Choice -The portion of the sacrolemma that is found at the neuromuscular junction -A protein that binds oxygen in the cardiac muscle cell -Complex membrane junctions that include desmosomes and gap junctions -The functional unit for muscle contraction, like sacromeres in skeletal muscles

Complex membrane junction that include desmosomes and gap junctions

1. Functions of muscles include A. heartbeat. B. muscle tone. C. moving bones. D. all of the above.

D

10. Transverse tubules and sarcoplasmic reticulum are well developed in A. smooth muscle fibers. B. skeletal muscle fibers. C. cardiac muscle fibers. D. skeletal and cardiac muscle fibers.

D

11. The functional unit of muscle contraction is A. the muscle. B. the muscle fiber. C. the myosin cross-bridge. D. the sarcomere.

D

Threshold stimulus is the Multiple Choice -maximum stimulus required to release acetylcholine. -minimum stimulus required to produce ATP. -maximum stimulus required to contract a muscle. -minimum strength of stimulation required to contract a muscle fiber.

Minimum strength of stimulation required to contract a muscle fiber

Place in order, from largest to smallest, the components of a skeletal muscle. M,F,M,M,F

Muscle Fascicle Muscle fiber Myofibril Filaments

Match the description with the correct component of a muscle fiber. Threadlike bundles of thick and thin filaments

Myofibril

The characteristic reddish brown color of skeletal muscle comes from which substance? Multiple Choice -Actin -Calcium -Myosin -Myoglobin

Myoglobin

Match each description with the correct muscle protein. Forms cross-bridges

Myosin

The electrical impulse that moves over the surface of a muscle fiber and into the T tubules results from increased membrane permeability to what ion? Multiple Choice -Chloride -Calcium -Hydrogen -Sodium

Sodium

Which of the following is not true? Multiple Choice -Red fibers have fewer mitochondria than white. -Red fibers contract more slowly than white. -Red fibers fatigue more slowly than white. -Red fibers contain more myoglobin than white.

Red fibers have fewer mitochondria than white

Match the description with the correct component of a muscle fiber. Functional unit of contraction within muscle fiber

Sarcomere

Match the description with the correct component of a muscle fiber. Cytoplasm of muscle fiber

Sarcoplasm

What happens to the A bands in a contracted muscle? multiple choice -The A bands do not change length. - The A bands shorten. -The A bands lengthen.

The A bands do not change length

What happens to the I bands in a contracted muscle? multiple choice -The I bands do not change length. -The I bands shorten. - The I bands lengthen.

The I bands shorten

What is the H zone? multiple choice -The area with thick filaments only; no thin filaments -The area where thick and thin filaments overlap -The distance between A bands -The distance between thick filaments

The area with thick filaments only; no thin filaments

What is the I band? multiple choice -The area with thin filaments only; no thick filaments -The length of the thin filaments -The area with thick filaments only; no thin filaments -The distance between Z lines

The area with thin filaments only; no thick filaments

What is the A band? multiple choice -The distance between Z lines -The length of actin filaments -The area that lacks thin filaments -The length of myosin filaments

The length of myosin filaments

Hundreds of mutations have been identified in RyR1 that contribute to multiple muscular diseases. Assume that a new mutation was discovered that causes this receptor to continually remain open. Based on what you know about the function of this receptor, how would you expect this new mutation to impact contraction? multiple choice -This mutation will increase the sensitivity of the DPH receptor to voltage changes, which will induce continued muscle contraction. -This mutation will decrease levels of calcium in the sarcoplasm, which will prevent muscle contraction. -This mutation will decrease the sensitivity of the DPH receptor to voltage changes,which will prevent muscle contraction. -This mutation will increase levels of calcium in the sarcoplasm, which will induce continued muscle contraction.

This mutation will increase levels of calcium in the sarcoplasm, which will induce continued muscle contraction

Match the description with the correct component of a muscle fiber. Channel formed by invagination of plasma membrane

Transverse (T) tubule

Match each description with the correct muscle protein. Blocks myosin binding sites

Tropomyosin

Match each description with the correct muscle protein. Location of binding sites for calcium

Troponin

82. In order to stimulate skeletal muscle fibers, motor neurons release the neurotransmitter ______.

acetylcholine

People with myasthenia gravis have a deficiency of Multiple Choice -troponin molecules. -titin molecules. -sarcomeres. -acetylcholine receptors

acetylcholine recceptors

Place each label on the appropriate filament. blue

actin, Troponin, tropomyosin, Thin filament

The two types of myofilaments are the thin filaments, composed primarily of the protein __________ , and the thick filaments, composed of __________ . multiple choice -actin; actin -actin; myosin -myosin; actin -myosin; myosin

actin; myosin

The muscle that causes an action is the Multiple Choice agonist -synergist. -mediator. -antagonist.

agonist

Determine whether each label describes skeletal or cardiac muscle. intercalated discs

cardiac muscle

Determine whether each label describes skeletal or cardiac muscle. involuntarily controlled

cardiac muscle

Determine whether each label describes skeletal or cardiac muscle. stimulation travels rapidly from cell to cell, causing contraction

cardiac muscle

Determine whether each label describes skeletal or cardiac muscle. Calcium ions from extracellular fluid and sarcoplasmic reticulum

cardiac muscle

Rigor mortis occurs after death because __________. multiple choice -the power stroke becomes stronger after death -detachment of crossbridges does not occur due to the lack of ATP -actin binding sites become permanently blocked so that crossbridge formation cannot occur -no calcium is present to bind to the regulatory protein tropomyosin

detachment of crossbridges does not occur due to the lack of ATP

Complete the sentences describing the connective tissue associated with skeletal muscles. Then put the sentences in the correct order to list the connective tissue layers from superficial to deep. Each muscle fiber within a fascicle is surrounded by a thin covering called a(n)

endomysium

89. The muscle that covers the upper part of the cranium is the _______________.

epicranius

Complete the sentences describing the connective tissue associated with skeletal muscles. Then put the sentences in the correct order to list the connective tissue layers from superficial to deep. The layer of connective tissue that closely surrounds a skeletal muscle is called the

epimysium

The presence of calcium in the sarcoplasm is directly responsible for __________. multiple choice -energizing the myosin head -exposing the binding sites on actin -decreasing the length of the myosin myofilament -the movement of actin toward the M line

exposing the binding sites on actin

Label the skeletal muscle organelles. openings into transverse tubules

outside layer

Name the connective tissue layer that separates a skeletal muscle into fascicles. Multiple Choice -Perimysium -Endomysium -Epimysium

perimysium

Another layer of connective tissue, called the ---, extends inward from the epimysium and separates the muscle tissue into groups of muscle fibers. These groups are called -----.

perimysium,fascicles

The discoloration and swelling that occurs with a muscle strain is due to Multiple Choice -excess myofibrils. -separated tendons. -severed nerves. -ruptured blood vessels.

ruptured blood vessels

An electrical impulse traveling along the sarcolemma and into transverse tubules causes calcium ions to diffuse from the __________ into the __________ . multiple choice -sarcoplasmic reticulum; sarcoplasm -sarcoplasm; sarcoplasmic reticulum -sarcolemma; sarcoplasm -sarcoplasm; sarcolemma

sarcoplasmic reticulum; sarcoplasm

Identify whether the following characteristics describe skeletal, smooth, or cardiac muscle tissue.Labels may be used more than once. Multiple nuclei

skeletal and cardiac muscle

Identify whether the following characteristics describe skeletal, smooth, or cardiac muscle tissue.Labels may be used more than once. has striations

skeletal and cardiac muscle

83. A forceful, sustained muscle contraction is called a ______ ______.

titanic contraction

Label the parts of a lever system. muscle contracting

top muscle

Label the muscle attachments to bone. orgins of biceps brachii

top of tendons

The binding of the chemicals to the muscle cell causes a electrical impulse to travel across the sarcolemma and down the --- tubules.

transverse

Identify each of the skeletal fiber structures indicated on the image below. trio of tubes

triad

77. The enzyme ATPase occurs in the globular portion of myosin molecules.

true

49. Short muscle cells with centrally located nuclei are A. smooth muscle fibers. B. skeletal muscle fibers. C. cardiac muscle fibers. D. striated muscle fibers.

A

45. Smooth muscle has ___________ and not troponin. A. calmodulin B. fibronectin C. norepinephrine D. titin

A

Place the steps of muscle fiber contraction in the correct sequence. A nerve impulse arrives at the distal end of a motor neuron axon. Tropomyosin molecules move to expose binding sites on actin

6

Place the steps of muscle fiber contraction in the correct sequence. A nerve impulse arrives at the distal end of a motor neuron axon. Thin filaments are pulled toward the center of the sarcomere by myosin

8

42. A muscle fiber exposed to a series of stimuli of increasing frequency combines individual twitches (summation) which results in A. complete sustained contraction. B. muscle tone. C. a latent period. D. flaccid muscles.

A

63. Which of the following is unique in that its insertion is to fascia and not bone? A. palmaris longus B. extensor carpi ulnaris C. flexor digitorum profundus D. extensor digitorum

A

Choose the correct statement about muscle contraction. Multiple Choice -Tropomyosin molecules move and expose specific sites on myosin filaments. -Filaments of troponin and tropomyosin slide past one another. -Actin filaments slide along myosin filaments -Cross-bridges form between actin and the sarcolemma.

Actin filaments slide along myosin filaments

67. Regina began an exercise program six months ago, and the muscles of her upper limbs and lower limbs are more prominent. Exercise can lead to formation of new muscle by A. stimulating synthesis of myoglobin. B. stimulating skeletal muscle cells to release IL-6, which stimulates satellite cells to divide, producing more muscle cells. C. stimulating connective tissue to differentiate as muscle tissue. D. stimulating motor neurons to divide and innervate more muscle cells.

B

71. A weightlifter uses muscles so the muscles exert more than 75% of their maximum tension, this stimulates A. an increase in slow, fatigable white fibers. B. muscle fibers developing new filaments of actin and myosin. C. shrinking of skeletal muscle. D. conversion of skeletal to smooth muscle.

B

72. Fibers of muscles whose motor neurons are severed A. hypertrophy. B. may be replaced by fat or fibrous connective tissue. C. cannot ever be reinnervated. D. die as their sarcomeres are progressively eliminated.

B

9. Muscle fibers are basically a collection of A. muscles. B. sarcomeres. C. connective tissue fibers. D. synapses.

B

Which of the following statements describes myofibrils? Multiple Choice -Modified endoplasmic reticulum; for calcium storage -Comprised of thick and thin filaments -Plasma membrane of a muscle fiber -Invaginations of the plasma membrane

Comprised of thick and thin filaments

12. Neurotransmitters are stored in vesicles in A. myofibrils. B. motor units. C. motor end plates. D. motor neuron endings.

D

18. Athletes usually experience muscle fatigue less quickly than nonathletes because they A. convert glucose to lactic acid. B. tolerate high concentrations of carbon dioxide. C. make more efficient use of ATP. D. produce less lactic acid.

D

19. At a neuromuscular junction, the muscle fiber membrane folds, forming a A. motor neuron. B. neurotransmitter. C. motor unit. D. motor end plate.

D

26. __________ degrades acetylcholine, keeping it from accumulating in the synapse. A. ATPase B. Myosinase C. Actinase D. Acetylcholinesterase

D

35. Threshold stimulus is the A. maximum stimulus required to release acetylcholine. B. minimum stimulus required to produce ATP. C. maximum stimulus required to contract a muscle. D. minimum strength of stimulation required to contract a muscle fiber.

D

46. When a muscle undergoes atrophy in response to disuse A. there is a reduction in capillary networks. B. the size of actin and myosin filaments decreases. C. the muscle gets smaller. D. all of the above.

D

5. A sarcomere is best described as A. a part of the sarcoplasmic reticulum. B. a group of fascicles. C. a group of muscle fibers. D. a unit within a muscle fiber.

D

52. Cardiac muscle A. contracts as a syncytium. B. excites itself. C. is only in the heart. D. all of the above.

D

56. A muscle that assists the agonist is a(n) A. antagonist. B. prime mover. C. mediator. D. synergist.

D

Identify each of the following regions of a sarcomere. space

H zone

During the contraction cycle, what is the result of ATP binding to myosin? Multiple Choice -Myosin binds to actin, forming cross-bridges. -Myosin heads pivot, undergoing a power stroke. -Myosin heads release from the binding site on actin. -Myosin heads are "cocked" into their high energy state.

Myosin heads release from the binding site on actin

Label the features of a neuromuscular junction. Myofibril

bundle of thick and thin filaments

An action, such as flexing the knee, is caused by the contraction of a muscle acting as an __________ and is opposed by a muscle acting as an __________. Multiple Choice antagonist; agonist agonist; antagonist

agonist; antagonist

Myasthenia gravis is Multiple Choice -a bacterial infection. -an autoimmune disorder. -a form of cancer. -the result of injury.

an autoimmune disorder

Determine whether each label describes skeletal or cardiac muscle. Functions to pump blood

cardiac muscle

Identify whether the following characteristics describe skeletal, smooth, or cardiac muscle tissue.Labels may be used more than once. Found in the wall of the heart

cardiac muscle

Identify whether the following characteristics describe skeletal, smooth, or cardiac muscle tissue.Labels may be used more than once. Function to pump blood

cardiac muscle

In what types of muscle does some of the calcium needed for contraction come from the extracellular fluid? Multiple Choice -Cardiac muscle and visceral smooth muscle -Visceral smooth muscle and skeletal muscle -Skeletal muscle and cardiac muscle

cardiac muscle and visceral smooth muscle

The structures that connect cardiac muscle cells are Multiple Choice -neuromuscular junctions. -intercalated discs. -motor end plates. -intervertebral discs.

intercalated discs

Label the features of a neuromuscular junction. motor end plate

location of receptors for neurotransmitter

At a neuromuscular junction, the muscle fiber membrane folds, forming a Multiple Choice -motor neuron. -motor unit. -neurotransmitter. -motor end plate.

motor end plate

The chemicals then bind to receptors located on the motor ----, a specialized area of the sarcolemma.

motor end plate

Zoomed in features of a neuromuscular junction shaft

motor neuron axon

Identify each of the skeletal fiber structures indicated on the image below. big circle

myofibril

Determine whether each label describes skeletal or cardiac muscle. Functions to move bones

skeletal muscle

Determine whether each label describes skeletal or cardiac muscle. Most are attached to bones

skeletal muscle

For each label, determine whether it describes contraction of smooth muscle or contraction of skeletal muscle. Then place the label in the correct column. stretching results in reflexive contraction

skeletal muscle

For each label, determine whether it describes contraction of smooth muscle or contraction of skeletal muscle. Then place the label in the correct column. only response to stimulation is contraction

skeletal muscle

Identify whether the following characteristics describe skeletal, smooth, or cardiac muscle tissue.Labels may be used more than once. Found in skeletal muscle

skeletal muscle

Identify whether the following characteristics describe skeletal, smooth, or cardiac muscle tissue.Labels may be used more than once. No striations

smooth muscle

Calcium ions bind to __________ in order to initiate a muscle contraction. multiple choice -the sarcoplasmic reticulum -tropomyosin -troponin -the sarcolemma

troponin

Place the steps of muscle fiber contraction in the correct sequence. ACh is released into the synaptic cleft

1

Place the steps of muscle fiber contraction in the correct sequence. A nerve impulse arrives at the distal end of a motor neuron axon. The myosin heads link to the active sites on actin

7

47. Compared to skeletal muscle, smooth muscle A. contracts more slowly and relaxes more slowly. B. contracts more slowly and relaxes more rapidly. C. contracts more rapidly and relaxes more slowly. D. contracts more rapidly and relaxes more rapidly.

A

50. Both acetylcholine and norepinephrine can affect A. smooth muscle contraction. B. skeletal muscle contraction. C. synthesis of actin and myosin. D. exercise tolerance.

A

58. The muscle that adducts and flexes the arm is the A. coracobrachialis. B. pectoralis minor. C. levator scapulae. D. teres major.

A

61. The soleus is a muscle that forms part of the A. calf. B. buttocks. C. thigh. D. shoulder.

A

Describe how action potentials travel from the sarcolemma into the interior of the muscle fibers, resulting in the release of calcium ions into the sarcoplasm. Multiple Choice -Action potentials travel along the surface of the myofibrils. -Action potentials travel along the surface of the sarcoplasmic reticulum. -Action potentials travel along T tubles.

Action potentials travel along T tubles

15. The amount of oxygen liver cells require to support the conversion of lactic acid to produce glucose or glycogen is the A. refractory quantity. B. oxygen debt. C. anaerobic concentration. D. aerobic conversion.

B

17. Binding sites on the surface of actin allow the formation of cross-bridges with molecules of A. ATP. B. myosin. C. troponin. D. tropomyosin.

B

34. Skeletal muscles help maintain body temperature in that A. the more active they are, the more heat is used up. B. the more active they are, the more heat is released. C. excess myosin is quickly metabolized to yield heat. D. they conserve actin and myosin in cold weather.

B

36. A myogram is A. a chart that shows how many muscle cells a neuron synapses with. B. a recording of the events of a twitch. C. a measurement of muscle tone. D. a depiction of the results of a stress test.

B

38. An example of a partial but sustained contraction is A. knee jerking. B. muscle tone. C. a twitch. D. eye blinking.

B

40. The increase in the number of motor units activated as a result of more intense stimulation is called A. latency. B. recruitment. C. threshold stimulation. D. sustained contraction.

B

44. Smooth muscle lacks A. actin and myosin. B. transverse tubules and striations. C. myofibrils. D. nuclei and mitochondria.

B

48. The type of muscle cell that lacks transverse tubules, has a single nucleus, and is under involuntary control is A. skeletal muscle. B. smooth muscle. C. cardiac muscle. D. striated muscle.

B

53. Bones and muscles function as mechanical devices called A. lifts. B. levers. C. syncytia. D. ladders.

B

59. The muscle that opposes a particular action is called the A. synergist. B. antagonist. C. agonist. D. prime mover.

B

6. Transverse tubules A. store sodium ions for the action potential at the cell surface. B. transmit muscle impulses into the cell interior. C. store calcium ions. D. connect actin and myosin.

B

64. The triangle of auscultation, commonly used to hear sounds of respiratory organs, is located near the border of the A. pectoralis major and pectoralis minor. B. trapezius and latissimus dorsi. C. latissimus dorsi and serratus anterior. D. pectoralis major and serratus anterior.

B

66. A sign of aging of the muscular system is A. expansion of muscle fiber diameters. B. decreased supplies of myoglobin to muscles. C. excess ATP. D. increased creatine phosphate.

B

13. The enzyme acetylecholinesterase causes acetylcholine to A. bind to actin. B. be secreted from the motor end plate. C. decompose. D. form cross-bridges.

C

22. At a neuromuscular junction A. actin and myosin filaments slide past one another. B. troponin and tropomyosin exchange places. C. neurotransmitters are released. D. intercalated discs are synthesized.

C

23. The first event in muscle fiber contraction is that A. the muscle fiber membrane is stimulated and a muscle impulse travels deep into the fiber through transverse tubules. B. acetylcholine diffuses across a gap at a neuromuscular junction. C. acetylcholine is released from the end of the motor neuron. D. calcium ions diffuse from sarcoplasmic reticulum into the sarcoplasm and bind to troponin molecules.

C

37. A plank position is part of a yoga/Pilates workout. The person supports the body on the floor in a prone position with the arms and feet supporting the body. It is a little like the "up" position of a push-up, held for 30 to 60 seconds. Contraction of the abdominal muscles in a plank is most likely A. isotonic. B. eccentric. C. isometric. D. concentric.

C

39. Which of the following is not true? A. Red fibers contract more slowly than white. B. Red fibers contain more myoglobin than white. C. Red fibers have fewer mitochondria than white. D. Red fibers fatigue more slowly than white.

C

4. The striated appearance of skeletal muscle fibers results from the A. transverse tubule pattern. B. sarcoplasmic reticulum network. C. sarcomere organization. D. cisternae placement.

C

41. In a recording of a muscle twitch, the delay between the time a stimulus is applied and the time the muscle responds is called the A. refractory period. B. relaxation period. C. latent period. D. contraction period.

C

51. The structures that connect cardiac muscle cells are A. intervertebral discs. B. neuromuscular junctions. C. intercalated discs. D. motor end plates.

C

55. The muscle that causes an action is the A. synergist. B. antagonist. C. agonist. D. mediator.

C

69. People with myasthenia gravis have a deficiency of A. titin molecules. B. troponin molecules. C. acetylcholine receptors D. sarcomeres.

C

8. A tendon is ______, whereas an aponeurosis is ______. A. cordlike and connects bones to bones/ a broad sheet of dense connective tissue that connects muscles to muscles B. a broad sheet of dense connective tissue that connects muscles to muscles/ cordlike and connects bones to bones C. cordlike and connects muscles to bones/ a broad sheet of dense connective tissue that connects muscles to muscles D. a broad sheet of dense connective tissue that connects bones to bones/ cordlike and connects muscles to muscles

C

Which of the following describes smooth muscle contraction but not skeletal muscle contraction? Multiple Choice -Requires calcium to regulate muscle contraction -Contraction is a result of actin and myosin interaction. -Requires energy from ATP molecules -Hormones can inhibit muscle contraction

Hormones can inhibit muscle contraction

Which of the following best describes the role of calcium in muscle contraction? multiple choice -It binds to tropomyosin, moving troponin, so that myosin heads can bind to actin. -It binds to troponin, moving tropomyosin, so that actin heads can bind to myosin. -It binds to tropomyosin, moving troponin, so that actin heads can bind to myosin. -It binds to troponin, moving tropomyosin, so that myosin heads can bind to actin.

It binds to troponin, moving tropomyosin, so that myosin heads can bind to actin

Describe the role of acetylcholinesterase in stimulation of a muscle fiber. Multiple Choice -It is the enzyme that breaks down acetylcholine in the synaptic cleft, ending stimulation of the muscle fiber. -It is the enzyme found in the axon terminal that catalyzes the production of acetylcholine. -It is the inactive form of acetylcholine, found stored in the synaptic vesicles of the neuromuscular junction. -It is the type of receptor found in the motor end plate that binds acetylcholine, initiating an electrical impulse.

It is the enzyme that breaks down acetylcholine in the synaptic cleft, ending stimulation of the muscle fiber

Label the features of a neuromuscular junction. Synapse

Neuromuscular junction

Match the description with the correct component of a muscle fiber. Plasma membrane of muscle fiber

Sarcolemma

Identify each of the skeletal fiber structures indicated on the image below. green lining

T- tubule

This figure shows a pair of relaxed sarcomeres. Use the labels to indicate the various features of the striations of these sarcomeres. Labels may be use more than once. big line

Thin filament

Transverse (T) tubules are invaginations of the sarcolemma of a muscle cell. multiple choice True/False

True

Myofibrils are composed primarily of Multiple Choice -troponin and tropomyosin. -fascia and tendons. -actin and myosin. -perimysium and endomysium.

actin and myosin

If there was a high concentration of acetylcholine within the synaptic cleft, but little to no response at the motor end-plate, you would expect __________ to be the responsible neuromuscular-blocking agent. multiple choice -curare -botulinum toxin

curare

If it were possible to move the terminal cisternae further away from the T-tubules, it would __________. multiple choice -prevent the production of an action potential -increase the sensitivity of the sarcoplasmic reticulum, causing it to release large amounts of calcium -prevent the voltage signal from entering the T-tubules -interfere with the signal required for the release of calcium from the sarcoplasmic reticulum

interfere with the signal required for the release of the calcium from the sarcoplasmic reticulum

Fibers of muscles whose motor neurons are severed Multiple Choice -die as their sarcomeres are progressively eliminated. -may be replaced by fat or fibrous connective tissue. -hypertrophy. -cannot ever be reinnervated.

may be replaced by fat or fibrous connective tissue

Zoomed in features of a neuromuscular junction yellow mustard

mitochondrion

At this neuromuscular junction, a ----- releases a type of chemical called a neurotransmitter.

motor neuron

86. The rhythmic, wavelike motion produced by smooth muscles in tubular visceral organs is called _______.

peristalsis

During muscle contraction, ATP supplies energy for Multiple Choice -glycogen synthesis. -enzyme activity. -myofilament movement. -creatine phosphate synthesis.

myofilament movement

In order for muscle contraction to occur, cross-bridges form between __________. multiple choice -myosin and actin -actin and troponin -myosin and tropomyosin -troponin and tropomyosin

myosin and actin

Botulinum toxin causes muscle paralysis because __________. multiple choice -sodium is removed from the synaptic cleft -the acetylcholine receptors at the motor end-plate are blocked -calcium is removed from the neuromuscular junction -no acetylcholine enters the synaptic cleft

no acetylcholine enters the synaptic cleft

Acetylcholine causes an end-plate potential by triggering the __________. multiple choice -closing of calcium channels -closing of chloride channels -closing of sodium channels -opening of calcium channels -opening of chloride channels -opening of sodium channels

opening of sodium channels

At neuromuscular junctions, acetylcholine binds to __________. Multiple Choice -receptors in the muscle fiber membrane -troponin in the actin filament -myosin cross-bridges -sodium ions in the extracellular fluid

receptors in the muscle fiber membrane

Facial wrinkles, such as glabellar or "frown" lines, appear with aging as a result of natural, repetitive muscle contractions. Botox® helps alleviate the appearance of these wrinkles by __________. multiple choice -overstimulating the facial muscles to tighten their appearance -destroying the motor nerves that serve the muscles responsible for forming the wrinkles -relaxing the facial muscles that cause the wrinkles -overstimulating the facial nerves to produce a steady contraction of the facial muscles

relaxing the facial muscles that cause the wrinkles

The striated appearance of skeletal muscle fibers results from the Multiple Choice -sarcomere organization. -transverse tubule pattern. -sarcoplasmic reticulum network. -cisternae placement.

sarcomere organization

Muscle fibers are basically a collection of Multiple Choice -connective tissue -fibers. -synapses. -sarcomeres. -muscles.

sarcomeres

Identify each of the skeletal fiber structures indicated on the image below. spiderweb

sarcoplasmic reticulum

Determine whether each label describes skeletal or cardiac muscle. All calcium ions from sarcoplasmic reticulum

skeletal muscle

Determine whether each label describes skeletal or cardiac muscle. Each muscle cell needs to be stimulated by neurotransmitter to contract

skeletal muscle

Determine whether each label describes skeletal or cardiac muscle. voluntarily controlled

skeletal muscle

For each label, determine whether it describes contraction of smooth muscle or contraction of skeletal muscle. Then place the label in the correct column. contraction only in response to nervous stimulation

skeletal muscle

Identify whether the following characteristics describe skeletal, smooth, or cardiac muscle tissue.Labels may be used more than once. Functions to move bones at joints

skeletal muscles

For each label, determine whether it describes contraction of smooth muscle or contraction of skeletal muscle. Then place the label in the correct column. Contractions include peristalsis

smooth muscle

For each label, determine whether it describes contraction of smooth muscle or contraction of skeletal muscle. Then place the label in the correct column. Response to stimulation can be contraction or inhibition of contraction

smooth muscle

For each label, determine whether it describes contraction of smooth muscle or contraction of skeletal muscle. Then place the label in the correct column. slow to contract and to relax

smooth muscle

For each label, determine whether it describes contraction of smooth muscle or contraction of skeletal muscle. Then place the label in the correct column. can be stretched and still maintain tension

smooth muscle

For each label, determine whether it describes contraction of smooth muscle or contraction of skeletal muscle. Then place the label in the correct column. can contract in response to nervous stimulation or to hormones

smooth muscle

Identify whether the following characteristics describe skeletal, smooth, or cardiac muscle tissue.Labels may be used more than once. Functions in peristalsis and vasoconstriction

smooth muscle

Regina began an exercise program six months ago, and the muscles of her upper limbs and lower limbs are more prominent. Exercise can lead to formation of new muscle by Multiple Choice -stimulating skeletal muscle cells to release IL-6, which stimulates satellite cells to divide, producing more muscle cells. -stimulating synthesis of myoglobin. -stimulating connective tissue to differentiate as muscle tissue. -stimulating motor neurons to divide and innervate more muscle cells.

stimulating skeletal muscle cells to release IL-6, which stimulates satellite cells to divide, producing more muscle cells

What is the name of the space between a motor neuron and a muscle fiber at the neuromuscular junction? Multiple Choice -Cisternae -Motor end plate -Synaptic vesicle -Synaptic cleft

synaptic cleft

Zoomed in features of a neuromuscular junction blue space

synaptic cleft

Zoomed in features of a neuromuscular junction blue ball

synaptic vesicle

The functional unit of muscle contraction is Multiple Choice -the muscle fiber. -the sarcomere. -the myosin cross-bridge. -the muscle.

the sarcomere

Transverse tubules Multiple Choice -store sodium ions for the action potential at the cell surface. - actin and myosin. -transmit muscle impulses into the cell interior. -store calcium ions.

transit muscle impulses into the cell interior

The triangle of auscultation, commonly used to hear sounds of respiratory organs, is located near the border of the Multiple Choice -pectoralis major and serratus anterior -.pectoralis major and pectoralis minor. -latissimus dorsi and serratus anterior. -trapezius and latissimus dorsi.

trapezius and latissimus dorsi

75. A motor neuron and the muscle fibers that it controls constitute a motor unit.

true

79. ATP is necessary for muscle relaxation.

true