A blending of epimysium, perimysium, and endomysium that forms a broad sheet at the end of a muscle is known as a(n): ligament myofibril sarcomere aponeurosis

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A blending of epimysium, perimysium, and endomysium that forms a broad sheet at the end of a muscle
is known as a(n):


ligament

myofibril

sarcomere

aponeurosis


End of Question 1



Question 2




2

The three types of muscle tissue are:


skeletal,
cardiac, smooth

epimysium, perimysium, endomysium

voluntary, involuntary, resting

elastic, collagen, fibrous


End of Question 2



Question 3




3

Skeletal muscles are often called voluntary muscles because:


connective tissue harnesses generated forces v
oluntarily

ATP activates skeletal muscles for contraction

they contract when stimulated by motor neurons of the central nervous system

the skeletal muscles contain myoneural junctions


End of Question 3



Question 4




4

Repeating contractile units that
make up a myofibril are called:


sarcomeres

thick filaments

thin filaments

A bands


End of Question 4



Question 5




5

Nerves and blood vessels are contained within the connective tissues of the:


epimysium and endomysium

perimysium only

epimysium and p
erimysium

endomysium only


End of Question 5



Question 6




6

The thinfilaments consist of:


a helical array of actin molecules

a helical array of myosin molecules

a pair of protein strands wound together to form chains of myosin molecules

a

pair of protein strands together to form chains of actin molecules


End of Question 6



Question 7




7

The thick filaments consist of:


a pair of protein strands wound together to form chains of actin molecules

a helical array of actin molecules

a heli
cal array of myosin molecules

a pair of protein strands wound together to form chains of myosin molecules


End of Question 7



Question 8




8

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


crossbridge

sarcomere

motor unit

myoneural junction


End of Question 8



Question 9




9

The reason that control over leg muscles is less precise than control over the muscles of the eye
is:


many muscle fibers are controlled by many motor neurons

a single muscle fiber is controlled by
a single motor neuron

single muscle fibers are controlled by many motor neurons

many muscle fibers are controlled by a single motor neuron


End of Question 9



Question 10




10

The sliding filament theory explains that the physical change that takes pla
ce during contraction
is that:


the thick filaments are sliding toward the center of the sarcomere alongside the thin filaments

the thin filaments are sliding toward the center of the sarcomere alongside the thick filaments

the thick and thin filaments are

sliding toward the center of the sarcomere together

the Z lines are sliding toward the H zone


End of Question 10



Question 11




11

Troponin and tropomyosin are two proteins that can prevent the contractile process by:


covering

the active site and blocking the actin
-
myosin interaction

inactivating the myosin to prevent cross
-
bridging

causing the release of calcium from the sacs of the sarcoplasmic reticulum

combining with calcium to prevent active site binding


End of Question 1
1



Question 12




12

The amount of tension produced by an individual muscle fiber ultimately depends on the:


number of calcium ions released

number of contracting sarcomeres

all
-
or
-
none principle

number of pivoting crossbridges


End of Question 12



Qu
estion 13




13

The transmission of an action potential along the T tubules stimulates the release of calcium
from which structure in the sarcomere?


troponin

tropomyosin

terminal cisternae

sarcolemma

myofibril


End of Question 13



Question 14




14

The amount of tension produced in the skeletal muscle as a whole is determined by the:


internal tension produced by the stimulated muscle fibers

external tension produced by the stimulated muscle fibers

total number of muscle fibers stimulated

all of the
above


End of Question 14



Question 15




15

Peak tension production occurs when all motor units in the muscle contract in a state of:


wave summation

treppe

twitch

complete tetanus


End of Question 15



Question 16




16

In an isotonic contraction,
the:


tension in the muscle decreases as the resistance increases

crossbridges must produce enough tension to overcome the resistance

muscle length does not change as a result of the resistance

tension in the muscle varies as it shortens


End of Question 1
6



Question 17




17

Which of the following is an example of an isometric contraction?


picking up a toddler who is sitting on the floor

walking

flexing the biceps muscle while holding a 10
-
pound weight

holding a heavy stack of books above the ground


E
nd of Question 17



Question 18




18

A high blood concentration of the enzyme creatine phosphokinase (CPK) usually indicates:


serious muscle damage

the release of stored energy

the mitochondria are malfunctioning

an excess of energy is being produced


End of Question 18



Question 19




19

Mitochondrial activities are relatively efficient, but their rate of ATP generation is limited by the:


availability of carbon dioxide and water

energy demands of other organelles

presence of enzymes

availability of

oxygen


End of Question 19



Question 20




20

Which of the following has been correlated with muscle fatigue?


increased muscle performance resulting from an increased pain threshold

an increase in metabolic reserves within the muscle fibers

a

decline in pH within the muscle altering enzyme activities

an increase in pH within the muscle fibers affecting storage of glycogen


End of Question 20



Question 21




21

During the recovery period, the body's oxygen demand is:


elevated above normal r
esting levels

an irrelevant factor during recovery

unchanged

decreased below normal resting levels


End of Question 21



Question 22




22

Which type of muscle fiber would be dominant in a muscle like the gastrocnemius, a calf muscle
that contracts durin
g standing and walking?


intermediate fibers

slow fibers

fast fibers

white fibers


End of Question 22



Question 23




23

Extensive blood vessels, mitochondria, and myoglobin are found in the greatest concentration
in:


slow fibers

intermediate fibers

type II fibers

fast fibers


End of Question 23



Question 24




24

The length of time a muscle can continue to contract while supported by mitochondrial activities
is referred to as:


aerobic endurance

hypertrophy

recruitment

anaerobic endurance


End of
Question 24



Question 25




25

Which of the following could cause muscle atrophy?


paralysis

a lack of regular stimulation of muscle fibers

wearing a cast on a broken limb

all of the above


End of Question 25



Question 26




26

What type(s) of muscle tissue do(es) not contain sarcomeres?


cardiac

skeletal

smooth

all of the above


End of Question 26



Question 27




27

Structurally, smooth muscle cells differ from skeletal muscle cells because smooth muscle cells:


contain many
nuclei

possess striations

contain a network of T tubules

lack myofibrils and sarcomeres


End of Question 27



Question 28




28

Which of the following is necessary for smooth muscle contraction?


The zone of overlap must increase, but the length of the M

line remains constant.

Calcium ions must interact with calmodulin to trigger muscle contraction.

T tubules must transmit the action potential to the sarcoplasmic reticulum.

Sarcomeres must contract as a result of crossbridges forming between actin and myo
sin.


End of Question 28



Question 29




29

Smooth muscle contractions in the respiratory passageways cause:


decreased resistance to air flow

immediate death

increased resistance to air flow

no change in resistance to air flow


End of Question 29



Que
stion 30




30

Layers of smooth muscle in the reproductive tract of the female are important in:


movement of oocytes

movement of sperm if present

expelling of the fetus at delivery

all of the above


End of Question 30



Question 31




31

The
cardiovascular system uses which types of muscle?


cardiac and smooth

smooth and skeletal

cardiac, smooth, and skeletal

skeletal and cardiac


End of Question 31



Question 32




32

The area of the A band in the sarcomere consists of:


M line, H band, zon
e of overlap

Z line, H band, M line

thin filaments only

overlapping thick and thin filaments


End of Question 32



Question 33




33

The order of the sequential
-
cyclic reactions that occur at an active site during cross
-
bridging is:


attach, detach,
pivot, return

attach, return, detach, pivot

attach, return, pivot, detach

attach, pivot, detach, return


End of Question 33



Question 34




34

Excitation
-
contraction coupling forms the link between:


electrical activity in the sarcolemma and the initiat
ion of a contraction

depolarization and repolarization

the release of Ca++ to bind with the troponin molecule

the neuromuscular junction and the sarcoplasmic reticulum


End of Question 34



Question 35




35

Cardiac muscle has the feature of
automaticity, which is the ability to contract without neural
stimulation. Which of the following statements accurately explains this unique feature?


Specialized pacemaker cells within the heart determine the rate of contraction of heart muscle.

The heart

is full of fast muscle fibers and can contract quickly enough not to require neural stimulation.

Because cardiac muscle is not under voluntary control, it does not respond to neural stimulation.

Calmodulin interacting with calcium and myosin light chain k
inase triggers interactions between actin
and myosin.

None of the above.


End of Question 35



Question 36




36

The phases of a single twitch, in sequential order, are:


latent period, contraction phase, relaxation phase

relaxation phase, latent phase,
contraction phase

contraction phase, latent phase, relaxation phase

latent period, relaxation phase, contraction phase


End of Question 36



Question 37




37

After contraction, a muscle fiber returns to its original length through:


elastic

forces and the movement of opposing muscles

the tension produced by the initial length of the muscle fiber

involvement of all the sarcomeres along the myofibrils

the active mechanism for fiber elongation


End of Question 37



Question 38




38

A muscle
producing peak tension during rapid cycles of contraction and relaxation is said to be
in:


treppe

incomplete tetanus

complete tetanus

recruitment


End of Question 38



Question 39




39

The process of reaching complete tetanus is obtained by:


decreasin
g the concentration of calcium ions in the cytoplasm

activation of additional motor units

increasing the rate of stimulation until the relaxation phase is completely eliminated

applying a second stimulus before the relaxation phase has ended


End of
Question 39



Question 40




40

The bacterium Clostridium tetani causes prolonged muscle contractions by doing which of the
following?


competing for the ACh receptor sites on the motor end plate

inhibiting the mechanism that suppresses motor neuron acti
vity

causing a decrease in the amount of available ACh

releasing a toxin that causes flaccid paralysis


End of Question 40



Question 41




41

Which of the following would not be an effective source of energy for muscle contraction?


ATP

glycogen

DNA

cre
atine


End of Question 41



Question 42




42

The two mechanisms used to generate ATP from glucose are:


aerobic respiration and anaerobic glycolysis

ADP and creatine phosphate

cytoplasm and mitochondria

none of the above


End of Question 42



Question 43




43

In anaerobic glycolysis, glucose is broken down to pyruvic acid, which is converted to:


lactic acid

citric acid

glycogen

acetyl
-
CoA


End of Question 43



Question 44




44

Johnny, a 55
-
pound 6
-
year
-
old boy, wants to be as strong as s
ome of the professional weight
lifters he sees on television. He goes outside, grabs the front bumper of his mother's SUV, and attempts
to raise it off the ground. The SUV does not move, but Johnny has succeeded in demonstrating which
kind of muscle contra
ction?


concentric

isometric

eccentric

isotonic


End of Question 44



Question 45




45

On average, girls have smaller muscles and therefore less muscle mass than boys. Which
hormones cause this difference between girls and boys?


growth

hormone and testosterone

epinephrine and thyroid hormone

thyroid hormone and growth hormone

epinephrine and testosterone


End of Question 45



Question 46




46

The hormone responsible for stimulating muscle metabolism and increasing the force of
contra
ction during a sudden crisis is:


testosterone

growth hormone

thyroid hormone

epinephrine


End of Question 46



Question 47




47

The type of skeletal muscle fibers that have low fatigue resistance are:


intermediate fibers

type I fibers

slow fibers

fast

fibers


End of Question 47



Question 48




48

An example of an activity that requires anaerobic endurance is:


a 50
-
yard dash

a 10
-
mile bicycle ride

running a marathon

a 3
-
mile run


End of Question 48



Question 49




49

Athletes training to develop
anaerobic endurance perform:


infrequent, long, relaxing workouts

stretching, flexibility, and relaxation exercises

frequent, brief, intensive workouts

a combination of weight training and marathon running


End of Question 49



Question 50




50

The
major support that the muscular system gets from the cardiovascular system is:


nutrient and oxygen delivery and carbon dioxide removal

constriction of blood vessels and decrease in heart rate for thermoregulatory control

decreased volume of blood and rate

of flow for maximal muscles contraction

a direct response by controlling the heart rate and the respiratory rate