-
what 3 types ofmuscle tissues?
where are they located?
skeletal:packed into skeletal muscles make up 40% of body weight.striated,voluntary
cardiac: only in the walls of the heart, straited, involutary
smooth: in the walls of hollow organs,viseral non striated involutary
-
contractibility?
excitibilty?
1. long cells shorten and generate pulling forces
2. electrical nerve impulse stimulates the muscle cell to contract
-
extensibility?
elasticity?
1. can be stretched back to its original length by contraction of an opposing muscle
2. can recoil after being stretched
-
what are the functions of muscle tissues?
- 1. movement
- 2.squeezes fluid and other substances through hollow organs
- 3. maitnence of posture (lets body sit stand)
- 4. joint stabilization
- 5. heat generation(muscle contract cause shivering)
- 6. allows breathing to occur
-
each skeletal muscle is an_______. it consists mostly of ____ ______.
-
skeletal muscle contains _____ _____ ,blood vessels,and nerves,but muscle tissue is not a ______ ______.
- 1. connective tissue
- 2. connective tissue
-
______ are bundles of muscle cells; muscle cells are also called _____ _____
- 1. fascicles
- 2. muscle fibers
-
wat do connective sheaths do?
they bind a skeletal muscle and its fibers together.
-
epimysium?
dense connective tissue surrounding the entire muscle
-
perimysium?
surrounds each fascicle(group of muscle fibers)
-
endomysium/
a fine sheath of connective tissue wrapping each muscle cell
-
orgin?
insertion?
1. less moveable attachment site
2. more moveable attachment site
-
one bone will move one will move while the other boneremainds fixed. _____moves toward the _____
-
muscles attach to orgins and insertions by conective tissue in the from of ______or _______(broad tendon)
-
__________are ofetn present where terndons meet bones
bone markings
-
muscle fibers are composed of _______.
myofibrils are composed of __________.
myofilaments are composed of________.
- myofibrils
- myofilaments
- thin filaments
-
thin filaments contain?
thick filaments contain?
-
the plasma membrane of the muscle cell is called ?
sarcolemma
-
the cytoplasm of the muscle cell is called?
sarcoplasm
-
the basic unit of contraction of a skeletal muscle is ?
sarcomere
-
what are z discs?
what are thin filaments?
- 1. the boundaries of each sarcolemma
- 2. extend from the Z disc toward the center of the sarcomere
-
what are:
thick filaments?
A bands?
located in the center of the sarcomere;overlap the inner ends of the thin filaments
full length of the thick filament;includes the inner end of thin of the thin filaments(there is an overlap of thick and thin)
-
what are:
H zone?
I band?
center part of the A band where no thyin filaments occur (no over lap of thick and thin)
region with only thin filaments
-
myosin molecules contain the ?
myosin heads
-
actin chains contain?
- troponin
- tropomyosin
- and actin molecules
-
______________ __________ is composed of interconnecting tubules surrounding each myofibril.
_____ occur in pairs on either side of a _ _____.
- sarcoplasmic reticulum
- cisternae
- sarcolemma
-
some tubules form cross channels called?
terminal cisternae
-
a triad is composed of ?
a T tubule + 2 terminal cisternae
-
the _______ ______contains________ ___, the ions are released when the muscle is stimulated to _______;during stimulation calcium ionsduffuse through the sarcoplasm of the muscle celland trigger the _____ ______ ____;when the cell relaxes calcium is pumped back into the sarcoplasm retic.
- sarcoplasmic reticulum
- calcium ions
- contract
- sliding filament mechanism
-
what is tension?
the forc created by contracting muscles
-
what is the load?
a weight or force that opposes the contraction od the muscle
-
do muscles shorten or lenghten when they contract?
they shorten
-
events at teh neurotranmitter junction ________________________________ from a somatic motor neuron into________________________ in the muscle fiber
- convert a chemical signal
- an electrical signal
-
a muscle twitch is ?
one cycle of contraction followed by relaxation
-
what is motor unit?
a motor neuron and all of teh mjuscle fibers it innervates (controls)
-
a smooth sustained muscle contraction plateau resulting from high frequency stimulation is?
a complete tetanus
-
what is treppe?
"the stair case effect" it describes the staircase pattern of a muscle tracing that begins with smaller initial contractions and ends with full contrations
-
________ _______move loads but_______ ________ create force without movement
- isotonic contractions
- isometric contractions
-
skeletal muscle fibers are catagorized according to?
how they make energy (ATP)-aerobic vs anaerobic
how quickly they contract
-
skeletal muscle fibers are divided in to 3 classes?
- slow oxidative fibers
- fast glycolytic
- fast oxidative fibers
-
properties of slow oxidative fibers?
- dark red due to high myoglobin
- get energy from aerobic metabolic reaction
- have high # of mitochondria
- rich supply of capillaries
- contract slowly and resistant to fatigue
-
properties of fast glycolytic fibers?
- contain little myoglobin (white in color) few mitochondria
- twice the diameter of slow oxidative fibers
- contain more mylofilaments and generate more power
- depend on anaerobic pathways
- contract rapidly and tire quickly
-
properties of fast oxidative fibers?
- have an intermediate diameter
- contract quickly like fast glycoltic fibers
- are oxygen dependent
- high myoglobin content (red)
- rich supply of capillaries
- somewhat fatigue resistant
- more powerful than slow oxidative fibers
-
_______ energy used in the first 10-30 seconds of vigorous excercise.___ _____ _____system used;creatine phosphate contributes a _____ to___ to make ATP; _ creatine phosphate =_ ATP.
all _ types of skeletal fiber tyes use this system
- immediate
- ATP creatine phosphate
- phosphate
- ADP
- 1
- 1
- 3
-
___ ______ energy is used approx. 30-90 sec. into vigorous excercise. uses ___ to breakdown ____ to____ to_____.
_glucose = _ATP; used by ____ ______ _____.
- short term
- glycolysis
- glucose
- pyruvate
- lactate
- 1
- 2
- fast glycolytic fibers
-
___ _____ energy used approx. 2min of vigorous excercise, uses ________,_______ and _______ _______ ______ to fully______ glucose.
_ glucose =___ ATP.
used by ____ oxidative fibers and ____ oxidative fibers.
- long term
- glycolysis
- citric acid cycle(Kreb's cycle)
- electron transport chain
- oxidize
- 1
- 36
- slow
- fast
-
skeletal muscle characterisitcs?
- striated
- multinucleated
- under voluntary control (somatic NS)
- contains myofibrilscomposed of sarcomeres
- contain T tubules
- no gap junctions
- well developed sarcoplasmic reticulum
- fast contracting
- every fiber is controlled by a nerve
-
cardiac muscle characteristics?
- striated and branched
- uni or binucleate
- has intercalated discs
- under involuntary control (autonomic NS)
- contains myofibrils
- contains T tubules
- presence of gap junctions at the interclated discs
- less developed sarcoplasmic reticulum than skeletal muscle
- found only in the wall of the heart
- can contract without input from the nervous system
-
smooth muscle characterisitcs?
- unstriated and with a fuisform shape
- uninucleate
- under involuntray control (autonomic NS)
- does not contain myofibrils
- does not contain T tubules
- presence of gap junctions
- less developed sarcloplsmiic reticulum
- found in the walls of hollow organs
- can contract without input from the nervous system
-
effects of excercise on muscles:
an increase in muscle strength occurs because of _____ ______ and ________ _________ (increase in muscle size)
- neural adaptation
- muscle hypertrophy
-
when does neuro adaptation occur?
does hypertrophy occur at the same time?
- occurs in teh first 4 weeks of weight training
- occurs after the 4 week mark
-
what happens during neural adaptations?
- recruitment of more muscle fibers
- more inhibition of the antagonistic muscles
- reduced inhibition by teh golgi tendon organ
-
what does the gogli tendon organ do?
it senses tesion and responds by stimulating the the relaxation of the muscle to prevent injury
-
what causes muscle hypertrophy?
- not dues to the increase of muscle fibers
- due to the increase in the number of myofibrils in the muscle cell; the cell becomes thicke
-
what is flexability?
what is the purpose of flexibility training?
range of motion around a group of joints or joint
it decreases the risk of injury and can possibly enhance recuperation time and preformance
-
what is limbering?
"warming up" not like stretching, restores normal flexability of the muscles and tendons. no change in range of motion has been gained. it is important prior to excercise to prevent injury
-
what is stretching?
leads to actual lengthening of muscle fibers an propriceptors. stretching over long periods of time can lead to greater range of motion around the joints.
-
side effects of anabolic steroids ?
- small testes
- decreased infertility
- increased estrogen(men dev. breasts)
- inlarged prostate
- increased LDL decreased HDL
- increased heart atta ck
- and liver damage
-
what is muscular Dystrophy?
a group of muscle destroying diseases infected muscles become enlarged with fat and connective tissues causing muscles to degenerate
-
what is a strain?
tearing of the muscle also known as a muscle pull
|
|
