Deck 7: The Muscular System

Question 1

A sarcomere is

A)formed from myosin only.
B)the distance between Z lines.
C)the length of the H zone.
D)between the I bands.

Answer 1

B

Question 2

Striations are caused by a series of overlapping

A)myofilaments.
B)sarcomeres.
C)Z lines.
D)intercalated disks.

Answer 2

A

Question 3

The special name for the plasma membrane of a muscle fiber is the

A)sarcolemma.
B)sarcoplasm.
C)T tubules.
D)sarcoplasmic reticulum.

Answer 3

A

Question 4

Which type(s)of muscle tissue is/are found in the walls of hollow internal organs?

A)Cardiac
B)Skeletal
C)Smooth
D)Both smooth and skeletal are correct.

Question 5

Which of the following is NOT a function of skeletal muscles?

A)Generate heat
B)Maintain posture
C)Move food through the GI tract
D)Keep blood moving in veins and lymphatics

Question 6

Which of the following surrounds a muscle fiber?

A)Endomysium
B)Epimysium
C)Fascia
D)Perimysium

Question 7

Which of the following surrounds a fascicle?

A)Endomysium
B)Epimysium
C)Fascia
D)Perimysium

Question 8

Which term refers to a molecule stored in muscle fibers that binds oxygen for use in making ATP?

A)Myofilament
B)Myoglobin
C)Myofibril

Question 9

Which of the following surrounds a skeletal muscle?

A)Endomysium
B)Epimysium
C)Fascia
D)Perimysium

Question 10

Skeletal muscle is highly thermogenic;that is,is produces heat.How?

A)It breaks down ATP when it contracts;this produces heat.
B)The friction produced when actin and myosin slide past each other produces heat.
C)Skeletal muscle contracts around sweat glands,producing heat.
D)When myofilaments shorten,they release heat.

Question 11

The pressure of skeletal muscle contraction is important in maintaining blood circulation.

Question 12

Sarcoplasm is

A)smooth endoplasmic reticulum that stores calcium.
B)the plasma membrane of a muscle fiber.
C)tubules that surround myofibrils.
D)the cytoplasm of a muscle fiber.

Question 13

The extensions of the sarcolemma that carry the nerve impulses deep into the sarcoplasm are the

A)sarcolemmas.
B)myoglobins.
C)T tubules.
D)sarcoplasmic reticulums.

Question 14

The smooth ER that stores calcium ions in muscle fibers is the

A)sarcolemma.
B)sarcoplasm.
C)T tubules.
D)sarcoplasmic reticulum.

Question 15

Which type(s)of muscle tissue is/are striated?

A)Cardiac
B)Skeletal
C)Smooth
D)Both cardiac and skeletal are striated.
E)Both skeletal and smooth are striated.

Question 16

Which type(s)of muscle tissue is/are involuntary?

A)Cardiac
B)Skeletal
C)Smooth
D)Both cardiac and smooth are correct.

Question 17

Cardiac muscle fibers need outside nervous stimulation in order to contract.

Question 18

Which type(s)of muscle tissue has/have intercalated disks?

A)Cardiac
B)Skeletal
C)Smooth
D)Both cardiac and skeletal are correct.

Question 19

A bundle of muscle fibers is called a

A)sarcomere.
B)fascicle.
C)myofibril.
D)synergist.

Question 20

Myofibrils are bundles of

A)muscle fibers.
B)sarcoplasmic reticuli.
C)muscles.
D)myofilaments.

Question 21

Which of the following proteins is NOT a component of the thin filament?

A)Tropomyosin
B)Myosin
C)Troponin
D)Actin

Question 22

The I band is dark and split by a Z line.

Question 23

What does the term "power stroke" refer to?

A)The transmission of a signal from the motor neuron to the muscle fiber
B)The movement of the myosin head toward the center of the sarcomere
C)The shortening of the sarcomere
D)The cleaving of ATP into ADP and a phosphate

Question 24

What is released from axon terminals to stimulate a muscle fiber to contract?

A)Calcium ions
B)Acetylcholine
C)ATP
D)Troponin

Question 25

Myosin is

A)a protein.
B)the thin filament.
C)pulled inward during contraction.
D)All apply.

Question 26

Which of the following proteins found in myofilaments contain the cross bridges?

A)Myosin
B)Actin
C)Tropomyosin
D)Troponin

Question 27

One motor neuron and all of the muscle fibers it innervates is called a

A)neuromuscular junction.
B)nerve.
C)motor unit.
D)ganglion.

Question 28

What does calcium do during muscle contraction?

A)Binds to troponin
B)Binds to the cross bridges
C)Supplies energy
D)Hydrolyzes ATP

Question 29

The sliding filament theory of muscle contraction describes

A)how a sarcomere shortens.
B)the disappearance of the A band.
C)the movement of the myosin in relation to the actin.
D)All apply.

Question 30

What is ATP used for in the process of muscle contraction?

A)Pump calcium ions back into the sarcoplasmic reticulum
B)Power stroke of myosin cross-bridge
C)Release of myosin from actin
D)All apply.

Question 31

Botulism toxin blocks the release of acetylcholine from the motor neuron.What effect does this have on muscle contraction?

A)Muscle contractions are strengthened.
B)There isn't enough information in the question to predict.
C)Muscle contractions are weakened or absent.
D)More calcium would be released from the sarcoplasmic reticulum.

Question 32

The major protein found in thin filaments is ______;the main protein found in thin filaments is _______.

A)myosin;actin
B)actin;myosin

Question 33

After acetylcholine is released from the axon terminal,it

A)binds to its receptors in the sarcolemma.
B)binds to troponin to expose active sites on actin.
C)diffuses out of the sarcoplasmic reticulum.
D)binds to active sites on actin.

Question 34

What occurs immediately before an electrical signal travels along the sarcolemma?

A)Acetylcholine binds to its receptors.
B)Acetylcholine diffuses across the synaptic cleft.
C)Calcium is released from the sarcoplasmic reticulum.
D)Calcium binds to troponin.

Question 35

What is the role of ATP in the sliding filament theory?

A)Energizes the myosin cross-bridge
B)Breaks the link between actin and myosin
C)Both energizes the myosin cross-bridge and breaks the link between actin and myosin.

Question 36

What ion is necessary for cross-bridging?

A)Iron
B)Sodium
C)Potassium
D)Calcium

Question 37

The A band contains _______,while the H zone contains ______.

A)thin filaments;thick filaments
B)thick filaments;thin filaments
C)thick and thin filaments;thin filaments
D)thick and thin filaments;thick filaments

Question 38

What is the correct order of events in the sliding filament theory of muscle contraction? 1.Myosin head binds to actin
2)Calcium ions bind to troponin
3)Myosin cross-bridges bend,pulling actin toward center of sarcomere
4)ATP is split into ADP and P
5)Tropomyosin moves to expose active sites of actin
6)Sarcoplasmic reticulum releases calcium ions
7)ADP and P released from myosin

A)2,4,6,1,3,5,7
B)1,2,3,4,5,6,7
C)6,2,5,4,1,7,3
D)4,2,7,1,6,5,3

Question 39

Which specific event triggers the release of calcium from the sarcoplasmic reticulum?

A)Acetylcholine binds to its receptors.
B)An electrical signal travels down the transverse tubules.
C)Myosin binds to actin.
D)Calcium binds to troponin.

Question 40

A neuromuscular junction is where a ______ and a ______ come together.

A)neuron;neuron
B)muscle fiber;neuron
C)neuron;myofibril
D)T tubule;sarcoplasmic reticulum

Question 41

What is the sign that a person has accrued an oxygen debt?

A)Inability of muscle to contract
B)Rigor mortis
C)Heavy breathing
D)Fainting

Question 42

In smooth muscle,the thin filaments are attached to ______ that will draw the cell inward during contraction.

A)thick filaments
B)Z lines
C)dense bodies
D)myosin

Question 43

After nervous stimulation of the muscle cell has ceased,the calcium

A)is destroyed by cholinesterase.
B)is chemically bound to the filaments.
C)level in the sarcoplasm increases.
D)is actively pumped into the sarcoplasmic reticulum for storage.

Question 44

Rigor mortis occurs because

A)there is no ATP to relax the muscles.
B)the body temperature drops.
C)there are no brain waves.
D)there are no nerve signals.

Question 45

Latent period is

A)the time of receiving many impulses in rapid succession.
B)the period between stimulation and contraction.
C)the time when ATP is depleted.
D)the time of muscle relaxation.

Question 46

An accumulation of ______ causes cramping and fatigue in muscles.

A)carbon dioxide
B)oxygen
C)lactic acid
D)pyruvic acid

Question 47

What process provides most of a muscle's ATP?

A)Cellular respiration
B)Lactic acid fermentation
C)Creatine phosphate breakdown
D)Alcoholic fermentation

Question 48

During _______,lactic acid is produced.

A)cellular respiration
B)creatine phosphate breakdown
C)fermentation

Question 49

What is the role of myoglobin in muscle contraction?

A)Oxygen carrier in muscle
B)Blood carrier in muscle
C)ATP carrier in muscle
D)Creatine phosphate generator in muscle

Question 50

The stage of a muscle twitch that occurs from the point of stimulation to the beginning of contraction is called the _____ period.

A)latent
B)lag
C)contraction
D)refractory

Question 51

A sustained muscle contraction with no relaxation is called

A)a twitch.
B)a tetanic contraction.
C)fatigue.
D)oxygen debt.

Question 52

A single muscle contraction lasting a fraction of a second is a

A)myogram.
B)muscle twitch.
C)motor unit.
D)tetanic contraction.

Question 53

Athletes sometimes complain of oxygen debt,a condition that results when insufficient oxygen is available to completely break down pyruvic acid.As a result,the pyruvic acid is converted to

A)a strong base.
B)stearic acid.
C)hydrochloric acid.
D)lactic acid.

Question 54

Athletes who train rely more on cellular respiration than people who don't train.Their muscle fibers contain more

A)water.
B)fatty acids.
C)lactic acid.
D)mitochondria.

Question 55

Summation is

A)receiving many impulses in rapid succession.
B)the period between stimulation and contraction.
C)the depletion of ATP.
D)a single contraction that lasts only a fraction of a second.

Question 56

Which is the fastest way to supply energy to muscle fibers?

A)Creatine phosphate breakdown
B)Fermentation
C)Cellular respiration

Question 57

During cellular respiration,oxygen and glucose combine to form ATP,______,and water.

A)lactic acid
B)fatty acids
C)carbon dioxide
D)pyruvic acid

Question 58

Creatine phosphate functions in the muscle cell by

A)forming a temporary chemical compound with myosin.
B)forming a chemical compound with actin.
C)inducing a conformational change in the myofilaments.
D)storing energy that will be transferred to ADP to resynthesize ATP as needed.

Question 59

Of the three sources of energy in muscle cells,which occurs in mitochondria?

A)Cellular respiration
B)Fermentation
C)Creatine phosphate breakdown

Question 60

Which events occur during a muscle contraction?

A)The H zone decreases in size.
B)The I band increases in size.
C)The myofilaments shorten in length.
D)Actin pulls myosin toward the center of the sarcomere.

Question 61

The muscle that does most of the work for a particular movement is called the

A)prime mover.
B)synergist.
C)insertion.
D)antagonist.

Question 62

The gluteus maximus muscle is named for

A)its size and shape.
B)its size and location.
C)its shape and action.
D)its attachment and fiber direction.

Question 63

The latissimus dorsi muscle is a _______ muscle.

A)round
B)triangular
C)wide
D)huge

Question 64

The biceps femoris is named for

A)its shape and location.
B)its fiber direction and action.
C)its shape and number of attachments.
D)its number of attachments and location.

Question 65

The subscapularis muscle is

A)under the scapula.
B)above the scapula.
C)inferior to the scapula.
D)beside the scapula.

Question 66

Which muscle is named for its shape?

A)Frontalis
B)Masseter
C)Trapezius
D)Biceps brachii

Question 67

When muscles contract,they shorten.Therefore,the movement that muscles can make is to pull the insertion toward the origin.

Question 68

The extensor digitorum is named for

A)its action and attachment.
B)its location and action.
C)its size and attachment.
D)its number of attachments and shape.

Question 69

Which of the following is NOT a characteristic of slow-twitch fibers?

A)Have few capillaries
B)Small motor units
C)Have many mitochondria
D)Abundant supply of myoglobin

Question 70

Which of the following is NOT a characteristic of fast-twitch fibers?

A)Useful for bursts of energy
B)Fatigues quickly
C)Light in color
D)Mostly aerobic

Question 71

Which type of muscle fibers would be utilized for short periods of walking or jogging?

A)Slow-twitch fibers
B)Intermediate-twitch fibers
C)Fast-twitch fibers
D)Medium-twitch fibers

Question 72

The more stimulation a muscle receives,the more motor units are activated.This is called

A)fatigue.
B)oxygen debt.
C)recruitment.
D)hypertrophy.

Question 73

A low level of muscle contraction that maintains posture is called muscle

A)tone.
B)atrophy.
C)hypertrophy.
D)recruitment.

Question 74

Three discrete types of muscle fibers are identified on the basis of their fuel supply,oxygen supply,and tension.Which of the following athletic endeavors best represents the use of slow-twitch fibers?

A)A sprint by an Olympic runner
B)Swinging a baseball bat
C)Lifting weights
D)Mountain climbing

Question 75

Which of the following obeys the all-or-none law?

A)The whole muscle
B)A muscle fiber
C)The whole muscle and a muscle fiber

Question 76

The __________ raises your eyebrow.

A)masseter
B)frontalis
C)zygomaticus
D)orbicularis oculi

Question 77

The biceps brachii and triceps brachii in the upper arm

A)are antagonistic.
B)are synergistic.
C)depend upon activity to determine antagonism or synergism.

Question 78

When muscles are not used,they shrink or

A)atrophy.
B)hypertrophy.
C)antagonize.
D)fatigue.

Question 79

Which part of a muscle is on the bone that is stationary during that muscle's movement?

A)Insertion
B)Prime mover
C)Origin

Question 80

The end of a muscle that is attached to the bone that it moves is called the

A)origin.
B)insertion.
C)tendon.