Structure of Skeletal Muscle Tissue chapter 10

Question 1

epimysium

Answer 1

the outer layer encircling the entire muscle.
made of dense irregular connective tissue

Question 2

perimysium

Answer 2

a membrane that surrounds groups of 10 to 100 or more muscle fibers separating them into bundles called muscle fascicles.
Made of dense irregular connective tissue

Question 3

endomysium

Answer 3

a membrane that separates individual muscle fibers from each other.
Mostly of reticular fibers

Question 4

Tendon

Answer 4

Attaches a muscle to the periosteum of bone
made of collagen fibers and regular connective tissue

Question 5

ligament

Answer 5

dense regular connective tissue attaches bone to bone

Question 6

aponeurosis

Answer 6

sheetlike tendon joining one muscle with another or with bone
example: epicranial aponeurosis

Question 7

perichondrium

Answer 7

membrane that covers cartilage

Question 8

Flexor

Answer 8

skeletal muscle that decreases angle at a joint

Question 9

Pronator

Answer 9

movement of forearm turning palm posteriorly

Question 10

extensor

Answer 10

increases angle at a joint

Question 11

abductor

Answer 11

moves a part away from the midline

Question 12

supinator

Answer 12

turning palm anteriorly

Question 13

myology

Answer 13

study of muscles

Question 14

skeletal muscle tissue

Answer 14

striated and voluntary
move the bones of skeleton

Question 15

cardiac muscle tissue

Answer 15

striated and involuntary
most of heart wall

Question 16

smooth muscle tissue

Answer 16

in walls of hallow internal structures
non striated and involuntary

Question 17

adduction

Answer 17

“add” brings arm closer to midline

Question 18

skeletal muscle has the most _____

Answer 18

variations

Question 19

sarcolemma

Answer 19

the plasma cell membrane of a skeletal muscle

Question 20

sarcoplasma

Answer 20

the cytoplasma of the skeletal muscle

Question 21

sarcoplasmic reticulum (SR)

Answer 21

the endoplasmic reticulum of the skeletal muscle
stores calcium in muscle cell
fluid filled system of membraneous sacs that encircles each myofibril

Question 22

3 groups of proteins

Answer 22

1. contractile (actin and myosin and filaments) = shortens the muscle therefore generate force during contraction
2. regulatory (troponin and tropomyosin)= help switch contractions on and off
3. structural integrity proteins (maintains structure like 3 ring binder)

Question 23

what is the triad mechanism to stimulate overlap (contraction) of filaments?

Answer 23

T-tubule
Terminal Cistern
Calcium ions

Question 24

sarcomere =

Answer 24

a contractile unit of a muscle
The I and A bands

Question 25

as muscle contracts, what gets shorter?

Answer 25

myosin and actin get shorter as they overlap

Question 26

acetylcholine

Answer 26

muscle cell neurotransmitter which triggers muscle impulse

Question 27

synapse

Answer 27

a space btw the 2 membranes

Question 28

acetylcholine esterase

Answer 28

breaks down acetylcholine (the muscle cell neurotransmitter) and ends the impulse

Question 29

single twitch =

Answer 29

muscle contraction

Question 30

wave summation

Answer 30

2 twtiches

Question 31

white muscle fibers

Answer 31

rapid response

Question 32

dark muscle fibers

Answer 32

tryptophan more muscle activity/strength

Question 33

synergist muscle

Answer 33

a muscle that assists the prime mover by reducing undesired action or unnecessary movement

Question 34

antagonist muscle

Answer 34

a muscle that has an action opposite of prime mover and yields to the movement of the prime mover

Question 35

contraction cycle

Answer 35

the repeating sequence of events that causes the sliding of filaments

Question 36

steps of contraction cycle

Answer 36

1. myosin ATPase hydrolyzes ATP and becomes energized 2. myosin head attaches to actin forming a cross bridge 3. cross bridge generates force as it rotates towards the center of the sarcomere (powerstroke) 4. ATP bound to myosin head detaches it from actin and myosin head hydrolyzes ATP to return to original position, and binds to new site on actin as the cycle continues

Question 37

to start filament sliding what must happen?

Answer 37

an increase in calcium concentration in the sarcoplasm

Question 38

what must happen to turn off sliding process of filament? this makes muscle fiber relax

Answer 38

decrease calcium concentration in the sarcoplasm

Question 39

neuromuscular junction

Answer 39

is the synapse between a somatic motor neuron and a skeletal muscle fiber

Question 40

thick myofilament

Answer 40

myosin

Question 41

thin myofilament

Answer 41

actin

Question 42

contractions are generated by

Answer 42

sliding of thin filaments past thick filaments

Question 43

once terminal cisterne releases calcium, it will

Answer 43

bind to troponin

Question 44

______ and ______ are regulatory proteins bound to actin

Answer 44

troponin and tropomyosin

Question 45

what two chemical are needed for muscle contraction to occur?

Answer 45

calcium and ATP

Question 46

the chemical that accumulates in the muscle when oxygen is depleted

Answer 46

lactic acid

Question 47

sliding filament theory

Answer 47

muscle fibers shorten as the actin and myosin filaments pull on each other

Question 48

myofilament

Answer 48

contractile filament; may be thick or thin

Question 49

oxygen debt

Answer 49

added O2 over and above the resting O2 consumption, that is taken into the body after exercise

Question 50

the binding sites for the cross bridges are located on

Answer 50

actin

Question 51

In order to make ATP (adenosine triphosphate) in muscles, creatine phosphate (CP) transfers __________ to adenosine diphosphate (ADP).

Answer 51

phosphate

Question 52

ATP can be made in muscles from stored glucose. In muscles, glucose is stored in the form of __________.

Answer 52

glycogen

Question 53

Which of the following is the correct sequence for the production of ATP for muscle contraction?

Answer 53

CP, anaerobic respiration, aerobic respiration

Question 54

Calcium ions will cause the troponin/tropomyosin complex to move in such a manner as to expose the actin binding sites. The calcium ions are released from the __________.

Answer 54

sarcoplasmic reticulum

Question 55

Which of the following cells converts lactic acid back to pyruvic acid so pyruvic acid can be involved in producing ATP?

Answer 55

liver cells

Question 56

What is the role of tropomyosin in muscle contraction? Choose 1 answer:

Answer 56

To prevent myosin from continuing to slide up the actin filament

Question 57

What is the role of acetylcholine in calcium release?

Answer 57

Stimulates cellular contraction by opening voltage-gated ion channels

Question 58

myofibril

Answer 58

small structures in sarcoplasm and are the contractile organelles of skeletal muscle

Question 59

Sequence of muscle contraction

Answer 59

1. Motor nerve’s impulse action potential arrives at axon terminal of the neuromuscular junction 2. Calcium ions rush in and react with synaptic vesicles 3.Synaptic vesicles fuse with cell membrane 4.Acetylcholine released via process of exocytosis 5.Acetylcholine binds with receptor sites on motor end plate causing depolarization of motor end plate and sarcolemma 6Impulse travels T- tubules & sarcoplasmic reticulum (SR) 7.Calcium ions released 8Calcium binds with troponin 9.Shift of tropomyosin, make sites available for myosin 10.With ATP present, ATPase splits ATP to ADP + P + Energy 11.Myosin (S1 units) combine with actin 12.Sliding action of actin over myosin (Power Stroke) 13.Impulse stops to muscle: calcium ions rapidly return to SR 14Tropomyosin returns over active sites on actin and contraction ceases

Question 60

fascia

Answer 60

large connective tissue sheets that wrap around groups of muscles

Question 61

myoglobin

Answer 61

oxygen binding, iron containing protein in the sarcoplasm of muscle fibers; contributes to red color in muscle