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338 Cards in this Set
- Front
- Back
T or F
muscle tissues make up half of the body's mass |
true
|
|
What is the most distingusihing functionial characterisic of muscles?
|
is thier ability to transform chemical energy into directed mechanical energy
|
|
NAME
is thier ability to transform chemical energy into directed mechanical energy |
muscles
|
|
What are the three types of muscles?
|
(1)skeletal (2)cardiac (3)smooth
|
|
What are muscle fibers?
|
are skeletal and smooth muscles cells that are elongated
|
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NAME
are skeletal and smooth muscle cells are elongated |
muscle fibers
|
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What do muscle contractions depend on?
|
two kingds of myofilaments
|
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NAME
depends on two kinds of myofilaments |
muscle contractions
|
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What do the prefixes, myo, mys, or sacro, refer to?
|
muscle
|
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What are the different prefixes that refer to muscles? (3)
|
(1)myo (2)mys (3)sacro
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What is skeletal muscle tissue?
|
is packaged skeletal muscles
|
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NAME
is packaged skeletal muscles |
skeletal muscle tissue
|
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What are skeletal muscles?
|
are organs that attach to and cover the bony skeleton
|
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NAME
are organs that attach to and cover the bony skeleton |
skeletal muscles
|
|
NAME
are the longest muscle cells |
skeletal muscle fibers
|
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NAME
these muscles have striations and can be controled voluntary |
skeletal muscle fibers
|
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Skeletal muscle fibers have (1) and can be controled (2)
|
(1)striations (2)voluntaru
|
|
Which muscle fiber cells are the longest?
|
skeletal
|
|
What are striations?
|
are obvious stripes on skeletal and cardiac muscle cells
|
|
NAME
are obvious stripes on skeletal and cardaic muscle cells |
striations
|
|
NAME
this muscle is the only type subject to ctronolled to conscious control |
skeletal muscle
|
|
NAME
these muscles are responsible for overall body mobility |
skeletal muscle
|
|
What is cardiac muscle tissues?
|
occurs only in the heart where it constitutes the bulk of the heart walls
|
|
NAME
ocurs only in the heart where it constitutes the bulk of the heart walls |
cardiac muscle tissues
|
|
NAME
this muscle is striated and is not voluntary |
cardiac muscle tissues
|
|
What is smooth muscle tissues?
|
is found in the walls of hollow visceral organs such as the stomach, urinary bladder, and respiartory passages
|
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NAME
is found in the walls of the hollow visceral organs such as the stomach, urinary bladder, and respiratory passages |
smooth muscle tissues
|
|
NAME
this muscle has no striations and is not voluntary |
smooth muscles
|
|
Do smooth muscles have striations?
|
no
|
|
Which muscle are the involunatry muscles?
|
(1)smooth (2)cardiac
|
|
what are the functions of the smooth muscles?
|
to force fluids and other substances through internal body channels
|
|
NAME
the role of this muscle tissue is to force fluids and other substances through internal body channels |
smooth muscles
|
|
NAME
this muscle is described as being visceral, nonstriated, and involuntary |
smooth muscle tissue
|
|
What are (4) functional characteristics of muscle tissue?
|
(1)exictibalilty (2)Contractility (3)ectensibility (4)elasticity
|
|
What is exicability?
|
is the ability to receive and respond to a stimulus
|
|
What is a stimulus?
|
is any change in a environment whether inside or outside the body
|
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NAME
is an change in the environment whether inside or outside the body |
stimulus
|
|
NAME
is the ability to receive and respond to a stimulus |
exicability
|
|
What is contractility?
|
is the ability to shorten forcibly when adeuqatley stimualted
|
|
NAME
is the ability to shorten forcibly when adququatly streched |
contractility
|
|
What is extensibility?
|
is the ability to be streched or extended
|
|
NAME
is the ability to be streched or extened |
extensibility
|
|
What is elascticity?
|
is the ability of muscle fibers to recoil and resume its resting length after being stretched
|
|
NAME
is the ability of muscle fibers to recoil and resume its resting length after being stretched |
elascticity
|
|
Muscle fibers (1) when contracting
|
shorten
|
|
What are four important functions for the muscles? (4)
|
(1)movement (2)maintains posture (3)stabilizes joints (4)generates heat
|
|
NAME
there main imporant functions are movement, maintains posture, stabilizes joints, and generates heat |
muscles
|
|
Just about all movements of the human body and its parts are a result of a (1)
|
muscle contraction
|
|
NAME
these muscles are responsible for all locomotion and manipulation |
skeletal muscles
|
|
Skeletal muscles are responsible for all (1) and (2)
|
(1)locomotion (2)manipulation
|
|
Even as muscles pull on bones to cause movments, they (1) and (2) the joints of the skeleton
|
stabilze and strengthen
|
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NAME
these are also responsible for stabilze and strenghten the skeleton and joints |
muscles
|
|
Muscles generate (1) are they contract
|
heat
|
|
Why muscles generating heat when they contract, so important?
|
bc the heat is important in mantaining normal body temp
|
|
NAME
is a descrete organ made up of several kinds of different tissues |
skeletal muscles
|
|
In general, each muscle is served by (1), an (2), and by (3)
|
(1)one nerve (2)an artery (3)one or more veins
|
|
NAME
each of these, in general, has one nerve, an artery, and one or more veins |
each muscle cell
|
|
Each skeletal muscle fiber is supplied w a (1) that controls its activity
|
nerve ending
|
|
Muscle cells also give off large amounts of (1) that must be removed throug viens if contraction is to remain efficient
|
metabolic wastes
|
|
individual muscle fibers are wrapped and held together by several different (1)
|
connective tissue sheaths
|
|
What holds indivdual muscle fibers together?
|
by connective tissue sheaths
|
|
What do the connective tissue sheaths do for the muscle fibers?
|
support each cell and reinforce the muscle as whole
|
|
What are the different connective tissue sheaths of muscle fibers? (3)
|
(1)endomysium (2)Perimysium and fascicles (3) epimysium
|
|
What is Endomysium?
|
is a fine sheath of connective tissue consisting of mostly reticular fibers that surrounds each individual muscle fiber
|
|
NAME
is a fine sheath of connective tissue consisting of mostly reticular fibers that surrounds each indivdiual muscle fibers |
endomysium
|
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What are the different connective sheaths of musle fibers in order from internal to external? (3)
|
(1)endomysium (2)Perimysium and fascicles (3) epimysium
|
|
What are fasicles?
|
resemble bundles of sticks that are groups of wrapped endomysium within each skeletal muscle
|
|
NAME
resemble bundles of sticks that are groups of wrapped endomysium within each skeletal muscle |
fasicles
|
|
What are perimysium?
|
is a layer of fibrous connective tissue that surrounds each fascicle
|
|
NAME
is a layer of fibrous connectve tissue that surrounds each fascicle |
perimysium
|
|
What is epimysium?
|
is an "overcoat" of dense irregular connective tissue surrounding the whole muscle
|
|
NAME
is an "overcoat" of dense irregular connective tissue surrounding the whole muscle |
epimysium
|
|
T or F
all of the connective tissue sheaths are continous with one another |
true
|
|
When each muscle fiber contracts, they pull on (1) which in turn (2)
|
(1)connective sheaths (2)transmit the pulling force to the bone to be moved
|
|
Connective sheaths also contribute to the (1) of muscle tissue
|
natural elasticity
|
|
Most skeletal muscles span joints and are atatched to (1) in at least two places
|
bones
|
|
What happens when the muscle contracts?
|
the muscles insertion moves toward the orgin
|
|
What are the differ muscle attachments?
|
(1)indirect (2)direct
|
|
Direct muscle attachments are called (1)
|
fleshy attachments
|
|
(1) muscle attachments are also called fleshy attachments
|
direct
|
|
What is a direct muscle attachment?
|
is when the epimysium of the muscle is fused to the periosteum of the bone or perichondrium of the cartilage
|
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NAME
refers to when the epimysium of the muscle is fused to the periosteum of the bone or perichondrium of the cartilage |
direct muscle attachment
|
|
What is an indirect muscle attachment?
|
is when the muscle's connective tissue wrapping's extend beyound the muscle either as a ropelike tendon or aponeurosis
|
|
NAME
refers to when the muscle's connective tissue's wrappings extend beyound the muscle either as a ropelike tendon or aponeurosis |
indirect muscle attachment
|
|
What is aponeurosis?
|
is a sheetlike tendon that anchors the muscle to the connective tissue covering of a skeletal element
|
|
NAME
is a sheetlike tendon that anchors the muscle to the connective tissue coverings of a skeletal element |
aponeurosis
|
|
(1) attachements are more common
|
indirect
|
|
Why are indirect attachments more common?
|
bc of their durabilty and small size
|
|
Tendon (1)
|
conserve space
|
|
Each (1) is a long cylindrical cell w multiple oval nuclei arranaged just beneath its sarcolemna surface
|
skeletal muscle fiber
|
|
Each skeletal muscle fiber is a long (1)w multiple oval nuclei arranged just beneath its (2)
|
(1)cylindrical cell (2)sarcolemna
|
|
What is sarcolemna?
|
is the muscle fibers of the plasma membrane
|
|
NAME
is the muscle fibers of the plasma membrane |
sarcolemma
|
|
What is the sacroplasm?
|
are the muscle fibers of the cytoplasm
|
|
NAME
are the muscle fibers of the cyotplasm |
sacroplasm
|
|
What do sacroplasm contain? (2)
|
(1)glycosomes (2)myoglobin
|
|
NAME
contain both glysosomes and myoglobin |
sacroplasm
|
|
What is myoglobin?
|
is a red pigment that stores oxygen
|
|
NAME
is a red pigment that stores oxygen |
myglobin
|
|
What is hemoglobin?
|
is a pigment that transports oxygen in the blood
|
|
NAME
is a pigment that transports oxygen in the blood |
hemoglobin
|
|
Each muscle fiber contain a large number of rodlike (1) that run parellel to its length
|
myofibrils
|
|
What are myofibrils?
|
can be found in each muscle fiber and run parellel to its length
|
|
NAME
can be found in each muscle fiber and run parellel to its length |
myofibrils
|
|
NAME
account for 80% of a cell's volumne |
myofibrils
|
|
What are striations?
|
are repeating series of dark A bands and light I bands
|
|
NAME
are repeating series of dark A bands and light I bands |
striations
|
|
What are I bands?
|
are light bands evident along each myofibirl
|
|
NAME
are light bands evident along each myofibril |
I bands
|
|
What are A bands?
|
are dark bands evident along each myofibril
|
|
NAME
are dark bands evident along each myofibril |
A bands
|
|
What is H zone?
|
is a light stripe on the midsection of each band
|
|
NAMe
is a light stripe on the midsection of each band |
H zone
|
|
What is a M line?
|
is a dark line that biscets the H zone vertically
|
|
NAME
is a dark line that biscets the H zone vertically |
M line
|
|
What is a Z disc?
|
is a darker area that is a midline interruption of a I band
|
|
NAME
is a darker area that is a midline interruption of a I band |
Z disc
|
|
What is a sarcomere?
|
is the region of myofibril btwn two succseive discs
|
|
NAME
is a region of myofibril btwn two sussescive discs |
sarcomere
|
|
What are the functional units of skeletal muscles ?
|
sacromeres
|
|
The banding pattern of myofibrils arises from two orderly arrangements of two structures: (1) and (2)
|
(1)myofilaments
|
|
What are myofilaments?
|
are smaller structure inside the sacromers
|
|
NAME
are smaller structures inside of sacromers |
myofilaments
|
|
What are the different types of myofilaments? (2)
|
(1)thick (2)thin
|
|
What are thick filaments?
|
are myofilaments that extend the entire length of the A band
|
|
NAME
are myofilaments that extend the entire length of the A band |
thick filaments
|
|
What are thin filaments?
|
are myofilaments that extend across the I band and partway into the A band
|
|
NAME
are myofilaments that extend across the I band and partway into the A band |
thin filaments
|
|
What are Z discs composed of?
|
nebulin
|
|
What is nebulin?
|
is a protein that makes of the Z discs
|
|
NAME
is a protien that makes of the Z discs |
nebulin
|
|
What makes of the thick filaments?
|
myosin
|
|
What is myosin?
|
is the protien that makes of thick filaments
|
|
NAME
are the protiens that make of thick filaments |
myosin
|
|
Describe the structure of the protien myosin?
|
(1)has a rodlike tail and (2)terminating globular heads
|
|
The heads of myosin link the thick and thin filaments to togehter during (1)
|
contraction
|
|
the heads of (1) link the thick and thin filaments to together during muscle contraction
|
myosin
|
|
NAME PROTIEN
has two globular heads and a rodlike tail |
myosin
|
|
What is the cross bridge?
|
is where the myosin heads link the thick and thin filaments
|
|
NAME
is where the myosin heads link the thick and thin filaments |
cross bridge
|
|
Desribe the portions of the thick filament (2)?
|
(1) has smooth and (2)is studded with an array of myosin heads
|
|
NAME
has smooth and is studded w an array of myosin heads |
thick filament
|
|
The heads of myosin are (1) and (2)
|
(1)actin binding site (2)ATP binding sites
|
|
NAME
these are actin binding sites and ATP binding sites |
myosin
|
|
What protien makes of thick filaments?
|
actin
|
|
What is actin?
|
is a protien that makes of thick filaments
|
|
NAME
is a protien that makes of thick filaments |
actin
|
|
What are the subunits of actin?
|
G actin
|
|
What is G actin?
|
bear the active sites to which the myyosin heads attach during contraction
|
|
NAME
bear the active sites to which the myosin heads attach during contraction |
G actin
|
|
G actin are polymerized into long actin filaments called (1)
|
F actin
|
|
What is tropomyosin?
|
is a rod shaped protien that spirals about actin's core and help to stiffen it
|
|
NAME
is a rod shaped protien that spirals about actin's core and helps to stiffen it |
tropomyosin
|
|
in a relaxed muscle, (1) they block actin's sites so that myosin heads cannot bind to thin filaments
|
trpomyosin
|
|
in a relxed muscle, tropomyosin (1)
|
block actin's sites so that myosin heads cannot bind to thin filaments
|
|
What is a troponin?
|
is a 3 polypeptide complex
|
|
NAME
is a 3 polypeptide complex |
tropin
|
|
What are two major protiens in thin filaments? (2)
|
(1)tropin (2)tropomyosin
|
|
What are the three polypeptides complexes of tropin?
|
(1)TnI (2)Tnt (3)TnC
|
|
NAME
is made up of three polypetide chains: TnI, Tnt, and TnC |
tropin
|
|
What is TnI?
|
is an inhibitory subunit that binds to actin
|
|
NAME
is an inhibitory subunit that binds to actin |
TnI
|
|
What is TnT?
|
is an inhibitory subunit that binds to tropomyosin and helps to postion it on actin
|
|
NAME
is an inhibitory subunit that binds to tropomyosin and helps to position it on actin |
TnT
|
|
What is TnC?
|
is a inhibitory subunit that binds calicum ions
|
|
NAME
is an inhibitory subunit that binds calicum ions |
TnC
|
|
What is an elastic filament?
|
is composed of the protien titin
|
|
NAME
this filament is composed of the filament titin |
elastic filament
|
|
What is titin?
|
makes of elastic filaments
|
|
NAME
is a protien that makes up elastic filament |
titin
|
|
What are the functions of titin?
|
(1)holding the thick filaments in place and thus orgainazation of the A band (2)assisting the muscle cell to spring back into shape after being stretched
|
|
NAME
this protien's function include holding the thick filaments in place thus organization of the A band (2)assisting the muscle cell to spring back into shape after being stretched |
titin
|
|
Skeletal muscle fibers contain two sets of (1)
|
intracellular tubules
|
|
What are two sets of intrcellular tubules that make up skeletal muscle fibers? (2)
|
(1)the SR (2) T tubules
|
|
What does SR stand for?
|
sacroplasmic reticulum
|
|
NAME
is elaborate smooth er |
SR
|
|
What is SR?
|
is elaborate smooth er
|
|
NAME
the intacellular tubules of this fiber are SR and T tubules |
skeletal muscle fibers
|
|
What are terminal cisternae?
|
are perpendicular cross channels at the A band and I band junctions
|
|
NAME
is a perpendicular cross channels at A band - I band junction |
terminal cisternae
|
|
What is terminal cisternae?
|
is a perpendicular cross channel at A-band-I band junction
|
|
What is the major role of the SR?
|
is to regulate intracellular levels of ionic calicum
|
|
NAME
the major role of this is regulate the intracellular levels of ionic Ca |
SR
|
|
How does the SR regulate the levels of Ca?
|
by it stores Calcium and releases it on demand when the muscle fiber is stimulated to contract
|
|
NAME
it stores Ca and releases it on demand when the muscle fiber is stimulated to contract |
SR
|
|
(1) provides the final go for muscle contraction
|
Ca
|
|
Ca provides the final go for (1)
|
muscle contraction
|
|
NAME
an elongated tube formed by penetration of the sacromola cell at each A band-I band junction |
T tubules
|
|
What are T tubules?
|
are elongated tubes formed by penetration of the sacromola cell at each A band-I band junction
|
|
What are triads?
|
are successive groupings of three membranous structures
|
|
NAME
is the succesive groupings of three membraneous structures |
triads
|
|
What are the three susecvie groupings of traids?
|
(1)T tubules (2)2 terminal cisterna
|
|
What is muscle contraction ultimately controled by?
|
nerve initated electrical impulses
|
|
T tubules can be thought of as (1)
|
rapid telegraphy system that ensures that every myofiobril in the muscle fiber contracts virtually at the same time
|
|
NAME
these can be thought of as rapid telegraphy system that ensures that every myofiobril in the muscle fiber contracts virtually at the same time |
T tubules
|
|
What is contraction?
|
refers to the activation of myosin's cross bridges
|
|
NAME
refers to the activation of myosin's cross bridges |
contraction
|
|
How does shortening of muscle fibers ocur?
|
when the tension generated on the thin filaments exceeds the forces opposing shortening
|
|
NAME
ocurs when the tension generated on the thin filaments exceeds the forces opposing shortening |
shortening of muscle fibers
|
|
What is plate potenital?
|
is a local eletrical event
|
|
NAME
is a local eletrical event |
plate potential
|
|
Later, plate potenital can (1)
|
iginte an action potiental that spreads in all directions across the sacrolema
|
|
NAME
this can inginte an anction potential that spreads in all directions across the sarolemna |
plate potenital
|
|
What is the outside face's charge of a sacrolemna ?
|
postive
|
|
What is the inside face's charge of a sacromlemna?
|
negative
|
|
What is membrane potential?
|
is the difference in charge
|
|
NAME
is the difference in resting potiental |
membrane potential
|
|
What is the predominant extracellular ion in the sacrolemma?
|
Na
|
|
What is the predominant intracellular ion in the polarized sacrolemma?
|
k
|
|
T or F
the sacrolemma is relatively impermeable to both ions |
true
|
|
How do sodium channels open up?
|
an axonal terminal of a motor neuron releases ACH and causes a patch of the sacrolemma to become permeable to Na+
|
|
NAME
an axonal terminal of a motor releases AcH and causes a patch of sacrolemma to become permeable to Na+ |
the opening of sodium channels
|
|
What is the depoliraztion ?
|
is when Na enters the cell and the resting poteinal is decreased
|
|
NAME
is when Na enters the cell and the resting potential is decreased |
depolrization
|
|
if the stimulus is strongh enough, (1) is intiated
|
action potential
|
|
(1) changes the permeability of the adjacent patch
|
polartiy reversal of the inital patch of sacrolemma
|
|
the polarity reversal of the inital patch of sacrolemma can (1)
|
change the permeability of the adjacent patch
|
|
bc of the reversal of polarity causing the voltage regulated Na channels to open, the adjacent patch's (1)
|
depolirze
|
|
Na channels in the sacrolemma are (1)
|
voltage regulated
|
|
The (1) travels rapidly along the sacrolemma
|
action potential
|
|
The aciton potential travels rapdily along the (1)
|
sacrolemma
|
|
once the action potential is iniated, is it stoppable?
|
no
|
|
T or F
once initiated, the action potential is stoppable |
False
|
|
What happens once the action potential is initiated?
|
the aciton potential is unstoppable and results in the contraction of a muscle
|
|
(1) results in the contraction of a muscle
|
the iniatiation of the action potential
|
|
Immediatly after the depolirazation wave passes, the (1)
|
sacrolemma permeability changes
|
|
Immediatly after the (1), the sacrolemma permeability changes
|
depolarization wave passes
|
|
(1)channels close and (2) channels open
|
(1)Na (2)K
|
|
Na channels (1), and K channels (2)
|
(1)open (2)close
|
|
What does K+ do as it diffuses from the cell?
|
restores the eletrical polarity of the scarolemma
|
|
NAME
as this ion diffuses from the cell, it restores the eletrical polarity of the scarolemma |
K+
|
|
(1) diffuses from the cell
|
K+
|
|
Repolirzation and delporization ocur in (1) directions
|
same
|
|
(1) and (2) must ocur before the muscle can be stimulated again
|
(1)repolarization (2)depolarization
|
|
the ionic concentration of the resting state is restored by the (1)
|
Na K pump
|
|
How is the ionic concentration of the resting state restored?
|
by the Na K pump
|
|
What happens once the action potential is generated? (3)
|
(1)is propagated along the sacrolemma (2)travels down the T tubules (3)triggers Ca 2+ release from the terminal cisternae
|
|
NAME
once this is generated it is propagated along the sacrolemma, it travels down the T tubules, and triggers Ca2+ release from the terminal cisternae |
action potential
|
|
Ca 2+ binds to (1)
|
troponin
|
|
(1) binds to troponin
|
Ca2+
|
|
What does the binding of Ca2+ to troponin cause? (2)
|
(1)the blocking of action potential (2)actin active binding sites to be exposed
|
|
NAME
this causes the blocking of action potential and actin active binding sites to be exposed |
the binding of Ca2+ to troponin
|
|
(1) cross bridges alernately attach and detach
|
Myosin
|
|
Myosin cross bridges alernately (1) and (2)
|
(1)attach (2)detach
|
|
Thin filaments move (1)
|
toward the center of the sacromere
|
|
NAME
these filaments move toward the center of the sacromere |
thin filaments
|
|
What powers the cycling process?
|
hydrolysis of ATP
|
|
the hydrolyis of ATP powers what process?
|
cycling
|
|
What happens once Ca2+ is removed from the cell?
|
tropmyosin blockage is restored and the muscle fibers relax
|
|
NAME
tropymosin is restored and the muscle fibers relax when (1) |
Ca2+ is removed
|
|
When there is a low intracellular Ca2+ concentration what happens? (3)
|
(1)tropmyosin blocks the binding sites on actin (2)myosin cross bridges cannot attach to the binding sites on atcin (3)the relaxed state of the muscle is enforced
|
|
NAME
tropomyosin blocks the binding sites of actin, myosin cross bridges cannot attach to binding sites of actin, and the relaxed state of the muscle is reinforced. When does this ocur? |
when there are low intracellular levels of Ca2+
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What happens when there are high levels of intracellular Ca2+? (2)
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(1)addittional Ca binds to troponin (2)Ca-activated troponin binds an additonal two Ca2+ at a separate regulatory site
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NAME
when additional Ca binds to troponin and Ca-activated troponin binds an additional two Ca2+ at a separate regulatory site, (1) |
Ca2+ levels are high
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inactive tropinin binds two (1)
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Ca2+
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inactive (1) binds two Ca2+
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tropinin
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Ca activates (1)
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troponin
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Ca-activated troponin undergoes a (1)
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coformational change
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(1) undergoes a coformational change
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Ca-activated troponin
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What does the change in Ca-activated troponin cause?
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moves tropomyosin away from actin's binding sites
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(1) moves tropomyosin away from actin;s binding sites
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when Ca-activated troponin undergoes a confomrational change
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When Ca-actiavated troponin undergoes a conformational change, it moves (1)
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tropomyosin away from actin's binding sites
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Once tropomyosin moves away from actin's binding sites, the (1) can bind and cycle
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myosin head
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Once tropomyosin moves away from actin's binding sites, the myosin head can (1) and (2)
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bind and cycle
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What does myosin binding and cylcing permit?
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permits contraction to begin
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What permits contraction to begin?
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myosin binding and cycling
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What is contraction?
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is the sliding of the thin filaments by the myosin cross bridges
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NAME
is the sliding of the thin filaments by the myosin cross bridges |
contraction
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What are the sequential events of contraction?
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(1)cross bridge formation (2)working stroke (3)cross bridge detachement (4)cocking of the myosin head
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NAME
this sequential events of this process, include cross bridge formation, the working stroke, cross bridge detachment, and cocking of the myosin head |
contraction
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What happens when cross bridges form?
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myosin cross bridge attaches to the actin filament
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NAME
is when myosin cross bridge attaches to the actin filament |
formation of cross bridges
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What is the working power stroke?
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is when the myosin head pivots and pulls actin filaments toward the M line
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NAME
is when the myosin head pivots and pulls actin filaments toward the M line |
the working stroke
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What happens when the cross bridges dettach?
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ATP attaches to the myosin head and the cross bridges deattach
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NAME
ocurs when ATP attaches the myosin heads and the cross bridges deattach |
deatchment of cross bridges
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What is cocking of the myosin head
|
is when energy from the hydrolysis of ATP cocks the myosin head into a high energy state
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NAME
is when energy from the hydrolysis of ATP cocks the myosin head into a high energy state |
cocking of the myosin head
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NAME
refers to the activation of myosin's cross bridges |
contraction
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contraction refers to (1)
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the activation of myosin's cross bridges
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When does contraction ends?
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when cross bridges become inactive, the tension generated declines, and relaxation is induced
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NAME
ocurs when cross bridges become inactive, the tension generated declines, and relaxations is induced |
contraction ends
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T or F
contraction of muscle fibers and muscles is similar |
true
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What are two types of muscle contraction?
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(1)iosmetric contraction (2)iostonic contraction
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What is a isometric contraction?
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refers to inreasing muscle tension meaning the muscle does not shorten during contraction
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NAME
refers to increasing muscle tension meaning the muscle does not shorten during contraction |
isometric contraction
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What is isotonic contraction?
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refers to decreasing muscle length meaning the muscle shortens during muscle contraction
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NAME
refers to decresing muscle length meaning the muscle shortens during contraction |
iostonic contraction
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What is a muscle unit?
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is a motor neuron and all the muscle fibers it supplies
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NAME
is a motor nueron and all the muscle fibers it supplies |
motor unit
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T or F
the number of muscle fibers can vary from four to several hundred |
true
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Muscles that control (1) have small motor units
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fine movements
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Muscles that control fine movements have (1)
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small motor units
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What are some fine movments?
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movements of the eyes and fingers
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NAME
refers to the movement of the eyes and fingers |
fine movements
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(1) have large motor units
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large weight bearing muscles
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Large weight bearing muscles have (1)
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large motor units
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(1) from a muscle unit are spread through the muscle
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muscle fibers
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muscle fibers from a muscle units are (1)
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spread throughout the muscle
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Contraction of a single motor unit causes (1)
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weak contraction of the entire muscle
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(1) causes weak contraction of the entire muscle
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contraction of a single motor unit
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Why does the contraction of a single motor unit cause the weak contraction of the entire muscle?
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bc muscle fibers from a motor unit are spread throughout the whole muscle unit
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What is a muscle twitch?
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is the response of a muscle to a single breif threshold stimulus
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NAME
is a response of a muscle to a single brief threshold stimulus |
a muscle twitch
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What are the three stages of a muscle twitch?
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(1)latent period (2)period of contraction (3)period of relaxation
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What is the latent period?
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is the first few millisecounds after stimulation when exicitation- contraction coupling is taking place
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NAME
is the first few millisecound after stimuluation coupling is taking place |
latent period
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What is the period of contraction?
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when cross bridges actively form and the muscle shortens
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NAME
is when cross bridges actively form and the muscle shortens |
period of contraction
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What is the period of relaxation?
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is when Ca2+ is reabsorbed into the SR and muscle tension goes to zero
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NAME
is when Ca2+ is reabsorbed into the SR and muscle tension goes to zero |
period of relaxation
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What are graded muscle responses?
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are variations in the degree of muscle contraction (2)required for proper control of skeletal movement
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NAME
are variations in the degree of muscle contraction |
graded muscle responses
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NAME
are required for proper control of the skeletal movement |
graded muscle responses
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How are graded muscle responses graded (2)?
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(1)changing the frequency of stimulation (2)changing the strength of the stimulus
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(1) are graded by changing the frequency of stimulation, and changing the strength of the stimulus
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graded muscle responses
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a single stimulus results in a (1)
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muscle twitch
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a single (1) results in a muscle twitch
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stimulus
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T or F
muscle does not have time to completly relax |
True
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A frequently delivered stimuli increases (1)
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contractile force
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A frequently delivered (1) increases contractile forces
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stimuli
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More rapidly delivered stimuli result in (1)
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incomplete tenatus
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(1) can result in tenatus
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more rapidly delivered stimuli
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If stimuli are given quickly enough, (1)
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complete tenaus results
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If (1), complete tenaus results
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stimuli are given quickly enough
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What is thershold stimulus?
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the stimulus strength at which the first observable muscle contracion occurs
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NAME
the stimulus strength at which the first observable muscle contraction occurs |
thershold stimulus
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What is beyond threhold, (1)
|
move contracts more virgoursaly as stimulus strength is increased
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(1), move contracts more virgoursaly as stimulus strength is increased
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beyond threhold
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What controls the force of contraction?
|
is controlled by multiple motor unit summation
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|
NAME
is controlled by multiple motor unit summation |
force of contraction
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|
NAME
brings more and more muscle fibers into play |
recruitment
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recruitment brings (1) and (2)
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more and more muscle fibers into play
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What is the staircase effect?
|
increased contraction in repsonse to multiple stimuli of the same strength
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|
NAME
is the increased contraction in response to multiple stimuli of the same strength |
the staircase effect
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Why does muscle contraction increase? (2)
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(1)there is increasing availabilty of Ca2+ in the saroplasm (2)muscle enzymes systems become more efficeint bc heat is increased as the muscle contracts
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when muscle systems become more efficient because heat is increased as the muscle contracts, can cause (1)
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contraction to increase
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increasing availbilty of Ca2+ in the sacroplasm can cause (1)
|
contractions to increase
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