Deck 9: The Muscular System: Skeletal Muscle Tissue and Muscle Organization

Question 1

The main nerves and blood vessels supplying the individual muscle fibers are contained within and branch through which of the following

A)epimysium
B)endomysium
C)perimysium
D)the myoblasts
E)epimysium and perimysium

Answer 1

E

Question 2

The complex known as the triad consists of

A)actin, myosin, and myofilaments.
B)one A band, one H zone, and one I band.
C)one transverse tubule and two terminal cisternae.
D)myofilaments, myofibrils, and sarcomeres.
E)one sarcomere, one sarcoplasmic reticulum, and one sarcoplasm.

Answer 2

C

Question 3

Which of the following is the type of muscle found in the heart

A)skeletal muscle
B)cardiac muscle
C)smooth muscle
D)appendicular muscle
E)None of the answers are correct.

Answer 3

B

Question 4

Smooth muscles are primarily used to

A)generate heat.
B)pump blood through the circulation.
C)push substances through tubes.
D)help movements occur smoothly.
E)move bones.

Question 5

A skeletal muscle's blood supply is generally best described as

A)poor.
B)very good.
C)avascular.
D)sporadic.
E)None of the answers are correct.

Question 6

The connective tissue surrounding a bundle of muscle fibers is called

A)endomysium.
B)epimysium.
C)perimysium.
D)a tendon.
E)an aponeurosis.

Question 7

The sarcoplasmic reticulum is (the)

A)plasmalemma of skeletal muscle fibers.
B)cytoplasm of skeletal muscle fibers.
C)endoplasmic reticulum of skeletal muscle fibers.
D)extension of the skeletal muscle plasmalemma into the cell.
E)None of the answers are correct.

Question 8

The layers of connective tissue surrounding a skeletal muscle from the inside to the outside in correct order are

A)endomysium, perimysium, and epimysium.
B)epimysium, endomysium, and perimysium.
C)epimysium, perimysium, and endomysium.
D)endomysium, epimysium, and perimysium.
E)perimysium, epimysium, and endomysium.

Question 9

Which of the following features is NOT characteristic of muscle tissues

A)excitability
B)transmissive
C)contractility
D)extensibility
E)elasticity

Question 10

Why does a skeletal muscle fiber have more than one nucleus

A)During development, groups of embryonic cells fuse together to form a single muscle fiber.
B)During development, the nucleus of each myoblast replicates several times.
C)During development, the plasmalemmas of newly formed muscle fibers disintegrate, making many muscle cells into one.
D)During muscular activity, parts of each muscle fiber break down, and the remaining parts, including their nuclei, fuse into new combination fibers.
E)All of the answers are correct.

Question 11

Which of the following is a function of skeletal muscle

A)produce movement
B)maintain posture
C)support soft tissues
D)generate heat
E)All of the answers are correct.

Question 12

What characteristic of muscle tissue allows it to respond to a stimulation

A)excitability
B)elasticity
C)extensibility
D)contractility
E)None of the answers are correct.

Question 13

The connective tissues that surround skeletal muscles are collectively called

A)superficial fascia.
B)subserous fascia.
C)deep fascia.
D)aponeuroses.
E)None of the answers are correct.

Question 14

How many muscles are there in the muscular system

A)50
B)206
C)thousands
D)700+
E)116

Question 15

Why are skeletal muscles called voluntary

A)These muscles maintain a constant rhythm of contraction.
B)The individual can make a conscious decision to contract these muscles.
C)Only these muscles are stimulated to contract by the central nervous system.
D)All of the answers are correct.
E)None of the answers are correct.

Question 16

Which of these orders of muscle structures progresses from the smallest to largest in diameter

A)muscle, fascicle, muscle fiber, myofibril
B)fascicle, myofibril, muscle fiber, filament
C)fascicle, muscle fiber, myofibril, muscle
D)muscle, muscle fiber, myofibril, fascicle
E)myofibril, muscle fiber, fascicle, muscle

Question 17

The dark staining area of a sarcomere is the

A)H band.
B)A band.
C)I band.
D)Z line.
E)M line.

Question 18

Skeletal muscle fibers arise from embryonic cells called

A)myotomes.
B)myoblasts.
C)myomeres.
D)epimysium.
E)None of the answers are correct.

Question 19

The attachment of a muscle to a bone is called

A)a tendon.
B)an aponeurosis.
C)a ligament.
D)a capsule.
E)either a tendon or an aponeurosis.

Question 20

Actinin can be found at the

A)Z line.
B)M line.
C)H band.
D)I band.
E)A band.

Question 21

The membrane network that surrounds each myofibril in a sleeve like arrangement is the

A)actin.
B)endomysium.
C)sarcoplasmic reticulum.
D)myoneural junction.
E)endoplasmic reticulum.

Question 22

The sliding mechanism of myofilaments works when

A)the filaments detach from the muscle tendon.
B)the myosin heads of the thick filaments bind to active sites of the thin filaments.
C)the myosin heads pivot away from the M line.
D)the sarcomere relaxes and expands.
E)actin becomes energized by calcium ions.

Question 23

Each skeletal muscle fiberis controlled by a single

A)synaptic terminal.
B)motor end plate.
C)transverse tubule.
D)neuromuscular synapse.
E)brain cell.

Question 24

The organelle(s)unique to muscle that give(s)it contractile capabilities is (are)the

A)Golgi apparatus.
B)ribosomes.
C)myofibrils.
D)mitochondria.
E)endoplasmic reticulum.

Question 25

Troponin assists in controlling the interaction between myosin heads and thin filaments by

A)forming a long chain that covers the active sites.
B)holding the tropomyosin strands in place.
C)moving the tropomyosin molecules to expose the active sites.
D)assisting in the formation of the myofilaments.
E)both holding and moving the tropomyosin strands.

Question 26

Tropomyosin covering the active sites is an example of

A)competitive inhibition.
B)allosteric inhibition.
C)activation.
D)enzyme-substrate reaction.
E)noncompetitive inhibition.

Question 27

Which of the following is the first step in the sliding mechanism of muscle contraction

A)The myosin heads of the thick filaments bind to active sites on the thin filaments.
B)Myosin heads pivot toward the M line when cross-bridge binding occurs.
C)Thin filaments are pulled toward the center of the sarcomere.
D)The cross-bridges detach and return to their original positions.
E)A carbohydrate molecule is broken down to produce energy.

Question 28

The structure of each myosin molecule includes

A)a double myosin strand.
B)an attached elongated tail.
C)a free globular head.
D)All of the answers are correct.
E)None of the answers are correct.

Question 29

The sarcoplasmic reticulum stores

A)oxygen.
B)glucose.
C)ATP.
D)calcium ions.
E)glycogen.

Question 30

The portion of a sarcomere that contains the thick filaments and the zone of overlap is the

A)I band.
B)M line.
C)A band.
D)H band.
E)Z line.

Question 31

The structures within the muscle fiber that shorten to cause skeletal muscle fiber contraction are (the)

A)myoneural junctions.
B)myofibrils.
C)sarcoplasm.
D)All of the answers are correct.
E)None of the answers are correct.

Question 32

The function of T tubules is to

A)bind muscle fibers together at the neuromuscular synapse.
B)separate one muscle fiber from another to facilitate partial contraction of a muscle.
C)help distribute the electrical signal to contract throughout the muscle fiber.
D)bind actin and myosin molecules together.
E)None of the answers are correct.

Question 33

Which of the following ions is essential to muscle contraction

A)sodium
B)chloride
C)calcium
D)sulfate
E)acetylcholine

Question 34

When contraction occurs,

A)the A band remains constant.
B)the H band gets smaller.
C)the I band begins to disappear.
D)the Z lines move closer together.
E)All of the answers are correct.

Question 35

Troponin is which of the following types of molecules

A)functional
B)fibrous
C)regulatory
D)enzyme
E)maintenance

Question 36

Which of the following is true of myosin molecules

A)They have a core of nebulin.
B)They make up the thin filaments.
C)They interact with the thick filaments.
D)They form the globular heads called cross-bridges.
E)All of the answers are correct.

Question 37

A very highly stretched muscle will produce a contraction that is

A)optimal.
B)much greater than average.
C)fairly weak.
D)slightly stronger than resting position.
E)None of the answers are correct.

Question 38

The area of a myofibril where there are no actin filaments is the

A)A band.
B)Z line.
C)I band.
D)M line.
E)H band.

Question 39

The motor neuron releases its neurotransmitter on a special region of the sarcolemma called

A)a T tubule.
B)the motor unit.
C)a fascicle.
D)a motor end plate.
E)the sarcoplasmic reticulum.

Question 40

The neurotransmitter involved in the process of contraction in skeletal muscles is

A)ATP.
B)acetylcholine.
C)troponin.
D)synovial fluid.
E)None of the answers are correct.

Question 41

Slow twitch fibers appear red due to the intracellular storage of

A)myoglobin.
B)blood.
C)hemoglobin.
D)glycogen.
E)All of the answers are correct.

Question 42

Due to lack of use, a muscle will lose size, tone, and power through the process of

A)hypertrophy.
B)recruitment.
C)atrophy.
D)reduced tone.
E)None of the answers are correct.

Question 43

Slow muscle fibers

A)are about two-thirds the diameter of fast fibers.
B)take twice as long to contract after stimulation as do fast fibers.
C)can continue to contract long after fast fibers have fatigued.
D)have less oxygen than do fast fibers.
E)None of the answers are correct.

Question 44

The largest muscle fiber type is

A)fast fibers.
B)slow fibers.
C)intermediate fibers.
D)cardiac fibers.
E)smooth fibers.

Question 45

All of the motor units of the muscle contracting at the maximal rate of stimulation causes the production of

A)the longest contraction.
B)the fastest contraction.
C)multiple motor unit summation.
D)peak tension.
E)fast, long contractions.

Question 46

While wearing a cast due to breaking a bone, muscle shrink due to the process of

A)recruitment.
B)cell division.
C)hypertrophy.
D)atrophy.
E)chronic inflammation, or swelling.

Question 47

Most of the time whole muscles do not contract at full strength because

A)only a few motor units are recruited.
B)we tend not to need the full capabilities of our muscles.
C)commonly the load is only the weight of our own body.
D)the muscle fibers will use up their energy reserves and the muscle will be forced to relax.
E)All of the answers are correct.

Question 48

All the muscle fibers controlled by a single motor neuron constitute a

A)sarcomere.
B)tendon organ.
C)motor unit.
D)skeletal muscle.
E)synaptic knob.

Question 49

The number of cells per motor unit in the leg muscles is most likely

A)one hundred.
B)less than a dozen.
C)millions.
D)hundreds to thousands.
E)many thousands.

Question 50

Fast muscle fibers are the only type of fibers that occur

A)in the eye and the hand.
B)in the large muscles of the thigh and calf.
C)in the muscles of facial expression.
D)in the muscles that attach to the axial skeleton.
E)in an adult; they are present only in a juvenile.

Question 51

Which of the following events occurs first

A)Myosin cross-bridges attach to actin.
B)Calcium ions are released from the sarcoplasmic reticulum.
C)Calcium binds to troponin.
D)The myosin head pivots toward the M line.
E)The myosin head binds ATP and detaches from actin.

Question 52

Slow fibers primarily use which of the following for energy

A)glycogen
B)lipids
C)carbohydrates, lipids, and proteins through the aerobic pathway
D)anaerobic metabolism
E)protein

Question 53

The greater the number of muscle fibers in each motor unit,

A)the greater the number of stimuli required to produce a contraction.
B)the longer each contraction will last.
C)the slower the contraction of the muscle will be.
D)the less precise the control will be.
E)None of the answers are correct.

Question 54

The enzyme in the synaptic cleft partly responsible for shutting down a muscle contraction is

A)myosinase.
B)actinase.
C)acetylcholinesterase.
D)epinephrinase.
E)calmodulin.

Question 55

A very good sprinter is likely to have

A)more slow twitch fibers than average.
B)more intermediate fibers than average.
C)more fast twitch fibers than average.
D)average muscles; performance is based solely on training.
E)None of the answers are correct.

Question 56

Which of the following is true of a muscle that is relaxing

A)The tendons are taut.
B)AChE is present in the synaptic cleft.
C)Released calcium ions are present.
D)Oxygen is depleted.
E)ATP levels are low.

Question 57

When a resting muscle contracts only enough to produce tension without movement, this is an example of

A)activation.
B)muscle tone.
C)hypertrophy.
D)atrophy.
E)twitch.

Question 58

What type of muscular activity is present in a muscle at rest

A)There is no activity.
B)There is some activity that causes the muscle to make continual tiny movements.
C)Motor units activate partially in a unified wavelike motion.
D)Motor units activate in a random pattern to cause slight constant tension, known as muscle tone.
E)There are large amounts of short contraction.

Question 59

When one motor neuron fires a single action potential the result affects one

A)upper motor neuron.
B)synaptic cleft.
C)lower motor neuron.
D)motor unit.
E)sensory unit.

Question 60

What is the significance of the change in permeability of the sarcolemma in muscle contraction

A)It has no role, because this phenomenon does not occur.
B)It causes the release of calcium ions.
C)This change is caused by a neurotransmitter.
D)This change is caused by the displacement of actin and myosin molecules.
E)None of the answers are correct.

Question 61

How does a muscle named lateralis differ from one named latissimus

A)There is no difference; the two terms are synonymous.
B)Lateralis refers to the side of the organism, whereas latissimus refers to the width of the structure.
C)Latissimus means the structure is larger than one that is merely lateralis.
D)Two muscles so named would have completely different functions.
E)A latissimus structure is always deep to a lateralis structure.

Question 62

Muscle fibers can have various arrangements. The most powerful arrangement is called

A)circular.
B)parallel.
C)pennate.
D)convergent.
E)None of the answers are correct.

Question 63

Adductor magnus is named partially due to the

A)size of muscle.
B)shape of muscle.
C)parallel versus pennate fibered muscles.
D)orientation of muscle fibers.
E)location of the muscle.

Question 64

Two factors that are used to determine the classification of a skeletal muscle are (1)the arrangement of the muscle fibers.
(2)the structural arrangement by which the muscles attach to the skeleton.
(3)the overall size of the muscle.
(4)the amount of connective tissue present within the muscle.
(5)the number of tendons connected to the muscle.

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

Question 65

In the case of the biceps brachii, the scapula is the ________; the radius is the ________.

A)origin; insertion
B)insertion; origin
C)agonist; antagonist
D)synergist, anergist
E)None of the answers are correct.

Question 66

The triceps brachii and biceps brachii are good examples of

A)muscles that flex the elbow.
B)an agonist-antagonist pair.
C)synergists.
D)agonists.
E)antagonists.

Question 67

The series of internal compartments of a muscle that contains a bundle of muscle fibers is a ________.

Question 68

If a muscle has a tendon that branches within the muscle tissue, it is (a)

A)sphincter muscle.
B)parallel fibered muscle.
C)circular muscle.
D)multipennate muscle.
E)None of the answers are correct.

Question 69

A muscle whose contraction is mostly responsible for a movement is said to be the ________ for that movement.

A)anergist
B)agonist
C)antagonist
D)prime mover
E)both agonist and prime mover

Question 70

A bundle of muscle cells within a muscle belly is called a

A)fascicle.
B)perimysium.
C)muscle sheath.
D)myofiber.
E)myofilament.

Question 71

Which of the following is or are properties of a lever

A)It is a flexible structure.
B)It is a fixed structure.
C)It moves on a fulcrum.
D)All of the answers are correct.
E)None of the above are correct.

Question 72

What does the term longissimus in a muscle name tell about that muscle

A)the muscle location in the body
B)the muscle length
C)the manner in which the fibers of the muscle are oriented
D)the direction in which the muscle fibers are oriented with respect to the long axis of the body
E)None of the answers are correct.

Question 73

The connective tissue fibers that divide the muscle into fascicles is called the ________.

Question 74

Which of the following words means slender

A)longissimus
B)brevis
C)latissimus
D)gracilis
E)major

Question 75

Regarding a muscle insertion, which of the following is true

A)The insertion moves more than does the origin.
B)The insertion is proximal to the origin.
C)As the speed of the muscle movement increases, the insertion moves further from the origin.
D)As the force of muscle contraction increases, the origin moves toward the insertion.
E)All of the answers are correct.

Question 76

What does the name flexor carpi radialis most likely mean

A)It is a medial forearm muscle.
B)It is a lateral forearm muscle that bends the wrist.
C)It is a parallel muscle.
D)The muscle attaches to the wrist.
E)The name means nothing.

Question 77

A lever in which the load is between the fulcrum and the applied force is a

A)first-class lever.
B)third-class lever.
C)second-class lever.
D)simple lever.
E)complex lever.

Question 78

A word in a muscle name that indicates it is a large muscle might be

A)brevis.
B)magnus.
C)longus.
D)minimus.
E)minor.

Question 79

The muscles surrounding the eyes and mouth are classified as

A)unipennate.
B)bipennate.
C)parallel fibered.
D)multipennate.
E)circular.

Question 80

A dense fibrous connective tissue layer that surrounds the entire skeletal muscle is the ________.