Term
| What are the three types of muscle? |
|
Definition
|
|
Term
| T/F All three types of muscle are striated. |
|
Definition
False
smooth muscle is non-striated |
|
|
Term
| T/F Cardiac and smooth muscle both deal with involuntary movements. |
|
Definition
|
|
Term
| T/F Skeletal muscle is the only muscle that deals with involuntary movements. |
|
Definition
false
deals with voluntary movements |
|
|
Term
| What is the difference between skeletal and cardiac muscle? |
|
Definition
cardiac is striated and involuntary movements
skeletal is striated and voluntary movements |
|
|
Term
| how many skeletal muscle is there? |
|
Definition
|
|
Term
| What is the percent of body weight that skeletal muscle accounts for? |
|
Definition
|
|
Term
| what are the three functions of skeletal muscle? |
|
Definition
force production for locomotion and breathing
force production for postural support
heat production during cold stress |
|
|
Term
| what are the two types of muscles that create the muscle actions? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| what is the function of extensors? |
|
Definition
|
|
Term
|
Definition
| surrounds the entire muscle |
|
|
Term
| what surrounds the bundles of fibers? |
|
Definition
|
|
Term
| what is the name for the bundles of muscle fibers? |
|
Definition
|
|
Term
|
Definition
| surrounds individual muscle fibers |
|
|
Term
|
Definition
|
|
Term
| T/F the sarcolemma is just on top of the endomysium. |
|
Definition
false
the sarcolemma is just BENEATH the endomysium |
|
|
Term
|
Definition
cytoplasm of the muscle cell
fluid matrix of the cell |
|
|
Term
| T/F one muscle has many fascicles->one fascicles has many fibers->i fiber has many myofibrils |
|
Definition
|
|
Term
|
Definition
| to increase blood flow to speed recovery |
|
|
Term
| what activates satellite cells? |
|
Definition
|
|
Term
| What happens when you break muscle? |
|
Definition
|
|
Term
| T/F no matter the intensity muscle will suffer damage |
|
Definition
|
|
Term
| T/F when muscle fibers are destroyed they can divide to replace to damaged ones |
|
Definition
false
muscle fibers CANNOT divide to replace damaged ones |
|
|
Term
| What is the marker in muscle that indicates muscle damage? |
|
Definition
creatine kinase
myoglobin
tripoin 1 |
|
|
Term
| What is the best marker of muscle damage? |
|
Definition
|
|
Term
| How are damaged muscles fixed? |
|
Definition
|
|
Term
| How do satellite cells work? |
|
Definition
| proliferate after injury and form myotubes which fuse to form muscle fibers |
|
|
Term
| Does muscle hypertrophy associate with satellite cells? |
|
Definition
|
|
Term
| Does muscle atrophy associate with satellite cells? |
|
Definition
|
|
Term
| What are the immune cells in muscle tissue? |
|
Definition
|
|
Term
| What increases with hypertrophy? |
|
Definition
|
|
Term
| What decreases with age in muscle? |
|
Definition
|
|
Term
| What is the function of myostatin? |
|
Definition
| inhibit functions of satellite cells |
|
|
Term
| by blocking myostatin, can we delay muscle mass loss with age? |
|
Definition
|
|
Term
| What is the distance between the Z line called? |
|
Definition
|
|
Term
|
Definition
| the distance between the z lines |
|
|
Term
T/F
muscles->
fasicles->
fibers->
myofibril->
filaments-> |
|
Definition
|
|
Term
| What is eccentric exercise? |
|
Definition
| lengthening of the muscle |
|
|
Term
| T/F eccentric exercise causes more damage. |
|
Definition
|
|
Term
| During muscle contraction which myofilament moves? |
|
Definition
|
|
Term
| T/F during muscle contraction actin doesn't move. |
|
Definition
|
|
Term
| In relation to the cross bridges, what happens during muscle contraction? |
|
Definition
| increases the number of cross bridges |
|
|
Term
|
Definition
| myosin head binding to actin |
|
|
Term
What myofilament is the A band associated with?
Does it change size during muscle contraction? |
|
Definition
|
|
Term
|
Definition
| space separating two sarcomeres |
|
|
Term
|
Definition
|
|
Term
|
Definition
| portion of myosin filament, no overlap with actin |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| What is the ratio of myosin to actin in one myofibril? |
|
Definition
|
|
Term
|
Definition
thick filament
comprises about 60% of muscle protein
1500 myosin filaments in each myofibril |
|
|
Term
|
Definition
thin filament
contains troponin and tripomyosin
3000 actin filaments in each myofibril |
|
|
Term
| T/F muscle contraction needs ATP. |
|
Definition
|
|
Term
| what are the contractile proteins? |
|
Definition
|
|
Term
| what are the regulatory proteins? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| in relation to muscle damage markers, how long does it take for troponin I to reach peak in blood after exercise? |
|
Definition
|
|
Term
| in relation to muscle damage markers, how long does it take for myoglobin to reach peak in blood after exercise? |
|
Definition
|
|
Term
| in relation to muscle damage markers, how long does it take for creatine kinase to reach peak in blood after exercise? |
|
Definition
|
|
Term
| Why is troponin I the most important direct marker of muscle damage? |
|
Definition
comes directly from the muscle
only takes 6 hours after exercise to be detected |
|
|
Term
|
Definition
|
|
Term
| What is the function of the t tubule? |
|
Definition
| transmit nerve impulse to induce release of Ca from the SR |
|
|
Term
| what must happen for the muscle to contract? |
|
Definition
|
|
Term
which of the following can store Ca?
terminal cisternae
SR
t tubule |
|
Definition
|
|
Term
| What is the major site of Ca storage? |
|
Definition
|
|
Term
| what is the sarcoplasmic reticulum (SR)? |
|
Definition
| longitudinal network of channels surrounding myofibril storage sites for Ca |
|
|
Term
| what are the transverse tubules? |
|
Definition
t tubules
extensions of the sarcolemma and run perpendicular through the muscle fiber
PERMIT NERVOUS IMPULSES TO PENETRATE TO MYOFIBRILS |
|
|
Term
| what is another name for the terminal cisternae? |
|
Definition
|
|
Term
| what is the terminal cisternae? |
|
Definition
enlarged portions of the SR
pass between two terminal cisternae |
|
|
Term
| What does the neuromuscular junction consist of? |
|
Definition
motor unit
neuromuscular joint
motor end plate
neuromuscular cleft |
|
|
Term
|
Definition
| motor neuron and all the muscle fibers it innervates |
|
|
Term
| what is the neuromuscular joint? |
|
Definition
| site where motor neuron meets the muscle fiber |
|
|
Term
| what is the motor end plate? |
|
Definition
| pocket formed around motor neuron by sarcolemma |
|
|
Term
| what is the neuromuscular cleft? |
|
Definition
| short gap between motor neuron and sarcolemma |
|
|
Term
| What happens in the neuromuscular junction? |
|
Definition
| ACh is released from the motor unit and diffuses across the neuromuscular cleft |
|
|
Term
| What happens to the end plate when ACh diffuses across the neuromuscular cleft? |
|
Definition
| causes an end-plate potential |
|
|
Term
| what is end-plate potential (EPP)? |
|
Definition
| depolarization of muscle fiber |
|
|
Term
| T/F EPPs never exceed threshold. |
|
Definition
false
always exceed threshold |
|
|
Term
| T/F EPSPs are sometimes referred to as mini-EPPs. |
|
Definition
|
|
Term
| What happens if you increase the number of cross bridges? |
|
Definition
| increase muscle contraction |
|
|
Term
| What is the sliding filament model mean? |
|
Definition
muscle shortens due to the movement of the actin filament over the myosin filament
formation of cross-bridges between actin and myosin filaments
reduction in the distance between Z lines of the sarcomere |
|
|
Term
| what happens to the H zone during muscle contraction? |
|
Definition
|
|
Term
| What happens to the A band during muscle contraction? |
|
Definition
|
|
Term
| What happens to the I band during muscle contraction? |
|
Definition
|
|
Term
| What happens to the actin filaments when the muscle is fully contracted? |
|
Definition
|
|
Term
| what happens to the H zone when the muscle is fully contracted? |
|
Definition
|
|
Term
| What are the two binding sites on the myosin head? |
|
Definition
|
|
Term
| T/F the myosin head is called a cross bridge when is it bound to actin. |
|
Definition
|
|
Term
| What covers the myosin binding site on actin during rest? |
|
Definition
|
|
Term
| What are the two heads of myosin for? |
|
Definition
ATP binding site
actin-binding |
|
|
Term
| T/F actin does not have myosin binding site. |
|
Definition
false
actin has a myosin binding site |
|
|
Term
| What is the action of tropomyosin for muscle contraction to occur? |
|
Definition
| tropomyosin must be moved away from the myosin-binding site so actin and myosin can interact |
|
|
Term
| How is tropomyosin moved away from the myosin-binding site? |
|
Definition
| troponin is activated by the release of Ca |
|
|
Term
| What are the three proteins troponin consists of? |
|
Definition
troponin T
troponin I
troponin C |
|
|
Term
| what is the function of troponin T? |
|
Definition
t for tropomyosin
at the troponin T loosely binds to tropomyosin to prevent it from moving off from actin |
|
|
Term
| what is the function of troponin I? |
|
Definition
i for inhibition
covers the myosin-binding site on actin to inhibit the interaction of actin and myosin at rest |
|
|
Term
| what is the function of troponin C? |
|
Definition
c for calcium
Ca-binding protein
when there is an increase in intracellular Ca, Ca binds to troponin C and causes a change in the troponin complex to allow tropomyosin off the myosin-binding site |
|
|
Term
| what are the sources for ATP for muscle contraction? |
|
Definition
| fat, carb, and protein metabolism |
|
|
Term
| how do we use ATP for muscle contraction? |
|
Definition
| power stroke produced by P to slide actin over myosin |
|
|
Term
does relaxation require energy?
where? |
|
Definition
| yes, on the myosin head ATP binding site |
|
|
Term
| where does the P come from for the power stroke? |
|
Definition
| when the cross bridge is formed P is released from ATP |
|
|
Term
| What is the role of P in muscle contraction? |
|
Definition
causes a conformational change in the myosin head
results in a power stroke
produce the sliding of the thin filament over the thick filament
causing muscle contraction |
|
|
Term
| What happens at rest to keep intracellular Ca low? |
|
Definition
| Ca ATPase helps to pump Ca into the SR to keep intracellular Ca low |
|
|
Term
| What are the steps of excitation-contraction coupling? |
|
Definition
1-electrical impuse
2-Ca release
3-bind to troponin C, move tropomyosin
4-ATP binds to myosin ATP binding site
5-ATP needed to pump Ca into SR
6-Ca detaches from troponin C, tropomyosin covers myosin-binding site |
|
|
Term
| What happens in step one of excitation-contraction coupling? |
|
Definition
| action potentials in the muscle cell membrane transmitted to t tubule by the spread of local currents |
|
|
Term
| what happens in step two of excitation-contraction coupling? |
|
Definition
| depolarization of the t tubules causes Ca channels to open-> Ca is released from the SR into the intracellular fluid of the muscle fiber |
|
|
Term
| what happens in step three of excitation-contraction coupling? |
|
Definition
| Ca binds to troponin C-> producing a conformational change in the troponin complex to allow tropomyosin off the myosin-binding site |
|
|
Term
| what happens in step four of excitation-contraction coupling? |
|
Definition
after the myosin head binds to actin to form a cross bridge, P is released from ATP.
P causes a conformational change to the myosin head, which results in the power stroke and sliding the thin over thick filament causing muscle contraction |
|
|
Term
| what happens in step five of excitation-contraction coupling? |
|
Definition
| Ca ATPase helps to pump Ca from intracellular fluid into SR to keep the intracellular Ca low |
|
|
Term
| what happens in step six of excitation-contraction coupling? |
|
Definition
| after Ca is removed from troponin C, tropomyosin is back to cover myosin-binding sites so that actin and myosin cannot interact |
|
|
Term
| What do we need to pump Ca into the SR? |
|
Definition
otherwise the muscle would be contracted all the time
waste of energy |
|
|
Term
|
Definition
reduced ability to do work
accumulation of ADP and P because ATP cannot be made |
|
|
Term
| what does it mean when there is a decrease in muscle force production? |
|
Definition
| reduced ability to perform work |
|
|
Term
| what are the contributing factors to muscle fatigue during high intensity exercise? |
|
Definition
| accumulation of lactate, H, ADP, P, and free radicals |
|
|
Term
| what are the contributing factors to muscle fatigue during long duration exercise? |
|
Definition
accumulation of free radicals
electrolyte imbalance
glycogen depletion
reduced motor drive to muscle from CNS |
|
|
Term
| If you have central fatigue do you have muscle fatigue? |
|
Definition
| not always, reduced ACh reduces the muscle contraction because the muscle cannot transmit and impulse |
|
|
Term
| What the the three muscle fiber types? |
|
Definition
|
|
Term
| what is the role of ATPase? |
|
Definition
|
|
Term
| What are the two classifications of muscle fiber types? |
|
Definition
biochemical properties
contractile properties |
|
|
Term
| what are the biochemical properties? |
|
Definition
oxidative capacity=# of capillaries, mitochondria, & myoglobin
type of myosin ATPase=speed of ATP degregation |
|
|
Term
| what are the biochemical properties of type I muscle fibers? |
|
Definition
slow
more mitochondria
more capillaries for increased gas exchange
more myoglobin to carry oxygen to the skeletal muscles
slower speed of ATP degradation |
|
|
Term
| what is another name for type 1 fibers? |
|
Definition
| slow-twitch muscle fibers |
|
|
Term
| what is another name for type 2 fibers? |
|
Definition
| fast-twitch muscle fibers |
|
|
Term
| how can we measure the number of mitochondria? |
|
Definition
|
|
Term
| what are the contractile properties? |
|
Definition
maximal force production=force per unit of cross sectional area
speed of contraction=myosin ATPase activity
muscle fiber efficiency |
|
|
Term
| what are the biochemical properties of type 2 fibers? |
|
Definition
less mitochondria
less capillaries
less myoglobin
fast speed of ATP degradation |
|
|
Term
| what are the characteristics of type 2x fibers? |
|
Definition
fast-twitch fibers
fast-glycolytic fibers
high myosin ATPase activity |
|
|
Term
| what are the characteristics of type 2a fibers? |
|
Definition
intermediate fibers
fast-oxidative glycolytic fibers
medium-high myosin ATPase activity |
|
|
Term
| what are the characteristics of type 1 fibers? |
|
Definition
slow-twitch fibers
slow-oxidative fibers
low myosin ATPase activity |
|
|
Term
| what fibers are used during intense exercise? |
|
Definition
| use more fast glycolysis, more type 2x and type 2a |
|
|
Term
| how are muscle fibers typed? |
|
Definition
|
|
Term
|
Definition
small piece of muscle is removed
slides stained to show different fibers |
|
|
Term
| what does the staining mean in a muscle biopsy? |
|
Definition
darkest=type 1
lightest= type 2a
in between= type 2x |
|
|
Term
| what are the factors that effect exercise performance in relation to fast twitch muscle fibers? |
|
Definition
|
|
Term
| do fast twitch fibers exert more force than slow twitch? |
|
Definition
|
|
Term
| T/F maximal force per cross sectional area is 10-20% higher in slow twitch fibers compared to fast fibers. |
|
Definition
false
10-20% higher force in fast fibers (type 2a and 2x) compared to slow fibers |
|
|
Term
| T/F force production is related to the number of myosin cross-bridges in strong binding sites. |
|
Definition
|
|
Term
| why is there a high maximal velocity in type 2x fibers compared to type 1 fibers? |
|
Definition
| the myosin ATPase activity |
|
|
Term
| T/F high force means high fatigue. |
|
Definition
|
|
Term
| what does it mean in relation of VO2 when someone has more slow twitch fibers? more fast twitch fibers? |
|
Definition
more slow twitch means greater VO2 max
more fast twitch means lower VO2 max |
|
|
Term
| what are the percentages of fiber types in non athletes? |
|
Definition
|
|
Term
| Power athletes, sprinters, have more of which fiber? |
|
Definition
|
|
Term
describe type 1 fibers.
# of mitochondria?
resistance to fatigue?
predominant energy system?
ATPase activity?
speed of shortening?
efficiency?
specific tension? |
|
Definition
high
high
aerobic
low
low
high
moderate |
|
|
Term
describe type 2a fibers.
# of mitochondria?
resistance to fatigue?
predominant energy system?
ATPase activity?
speed of shortening?
efficiency?
specific tension? |
|
Definition
high/moderate
high/moderate
combination
high
high
moderate
high |
|
|
Term
describe type 2x fibers.
# of mitochondria?
resistance to fatigue?
predominant energy system?
ATPase activity?
speed of shortening?
efficiency?
specific tension? |
|
Definition
low
low
anaerobic
highest
highest
low
high |
|
|
Term
| How can you use a VO2 max test to estimate the fiber types? |
|
Definition
a higher VO2 max most likely indicates more type 1 fibers
a lower VO2 max lost likely indicates more type 2a and 2x fibers |
|
|
Term
| endurance athletes, distance runners, how more of which fibers? |
|
Definition
| higher percentage of slow fibers |
|
|
Term
| T/F fiber type is the only variable that determines success in an athletic event. |
|
Definition
|
|
Term
| what is the distribution of fiber types in distance runners? |
|
Definition
|
|
Term
| what is the distribution of fiber types in track sprinters? |
|
Definition
|
|
Term
| what is the distribution of fiber types in non athletes? |
|
Definition
|
|
Term
| can muscle fiber types be altered with training? |
|
Definition
yes, a small percentage
determined by genetics |
|
|
Term
| T/F you can change fiber types from slow to fast. |
|
Definition
false
cannot change fiber types but can make them more oxidative, shifting type 2x to 2a |
|
|
Term
| what exercise can shift fiber types? |
|
Definition
| long-endurance exercise training |
|
|
Term
| what are the effects long-endurance exercise training on fiber types? |
|
Definition
shift from type 2x to type 2a
type 2a can be converted to type 1, if training persists |
|
|
Term
| how long do you have to train to change type 2a fibers to type 1 fibers? |
|
Definition
about 4 months
3-4 days a week |
|
|
Term
| how does strength training change skeletal muscles? |
|
Definition
|
|
Term
|
Definition
| increase in muscle fiber size |
|
|
Term
|
Definition
| increase in muscle fiber number |
|
|
Term
| how dos endurance training change skeletal muscle? |
|
Definition
| increase oxidative capacity |
|
|
Term
| T/F age is associated with a loss of muscle mass. |
|
Definition
|
|
Term
| how much muscle mass is lost between ages 25-50? |
|
Definition
|
|
Term
| how much muscle mass is lost between ages 50-80? |
|
Definition
|
|
Term
| T/F as age increases fast fiber numbers increase. |
|
Definition
fasle
as age increases fast fibers decrease |
|
|
Term
| T/F even with increase in age, increase in regular exercise training can improve strength and endurance, but cannot completely eliminate muscle mass loss with age. |
|
Definition
|
|
Term
| T/F muscle mass loss with age is linked to lower GH concentration. |
|
Definition
|
|
Term
| What are the two types of muscle action? |
|
Definition
|
|
Term
| what is isometric muscle action? |
|
Definition
muscle exerts force without changing length
pulling against immoveable object
postural muscles |
|
|
Term
| what is isotonic (dynamic) muscle action? |
|
Definition
concentric=muscle shortens during force production
eccentric=muscle produces more force but length increases |
|
|
Term
| which isotonic muscle action produces more muscle damage? |
|
Definition
|
|
Term
match muscle action and muscle length:
concentric
eccentric
isometric
with
no change
decreases
increases |
|
Definition
concentric-decreases
eccentric-increases
isometric-no change |
|
|
Term
|
Definition
contraction as a result of a single stimulus
latent period-5ms
contraction-tension developed-40ms
relaxation-50ms |
|
|
Term
| what are the three parts of a muscle twitch? |
|
Definition
latent period
contraction
relaxation |
|
|
Term
| why is the speed of shortening greater in fast fibers? |
|
Definition
SR releases Ca at a faster rate
higher myosin ATPase activity |
|
|
Term
| what are the three factors that regulate force generation? |
|
Definition
1)types and number of motor units recruited
2)initial muscle length (at time of contraction)
3)nature of the neural stimulation of motor units |
|
|
Term
| what types and number of motor units produce the most force? |
|
Definition
more motor units
fast motor units |
|
|
Term
| what is the ideal length for a skeletal muscle to produce the most force? |
|
Definition
|
|
Term
| T/F at the time of contraction,the muscle must be at the ideal length to produce the most force. |
|
Definition
|
|
Term
| T/F an increase in cross bridge formation will increase force. |
|
Definition
|
|
Term
| explain the frequency of stimulation. |
|
Definition
simple twitch: low frequency low force
summation: increasing frequency, increasing force
tetanus: highest frequency, highest force, steady state |
|
|
Term
| T/F at any absolute force, the speed of movement is greater in muscle with higher percent of fast fibers |
|
Definition
|
|
Term
| T/F the maximal velocity of shortening is greatest at greatest force. |
|
Definition
false
the maximal velocity of shortening is greatest at lowest force. |
|
|
Term
| T/F an increase in velocity = increase in force |
|
Definition
false
increase in velocity, does not mean an increase in force |
|
|
Term
| T/F increase in velocity = decrease in force production |
|
Definition
|
|
Term
| what happens after training in relation to force production? |
|
Definition
| same work load will generate more velocity |
|
|
Term
| What are the two reasons fast twitch shorten faster? |
|
Definition
Ca release
myosin ATPase activity |
|
|
Term
| T/F fast twitch fibers always produce less force. |
|
Definition
|
|
