Chapter 10 muscle tissue Flashcards
neurotransmitter that binds at a motor end-plate to trigger depolarization
acetylcholine (ACh)
protein that makes up most of the thin myofilaments in a sarcomere muscle fiber
actin
change in voltage of a cell membrane in response to a stimulus that results in transmission of an electrical signal; unique to neurons and muscle fibers
action potential
production of ATP in the presence of oxygen
aerobic respiration
formation of blood capillary networks
angiogenesis
broad, tendon-like sheet of connective tissue that attaches a skeletal muscle to another skeletal muscle or to a bone
aponeurosis
enzyme that hydrolyzes ATP to ADP
ATPase
loss of structural proteins from muscle fibers
atrophy
hearts ability to control it’s own contractions
autorhythmicity
regulatory protein that facilitates contraction in smooth muscles
calmodulin
striated muscle found in the heart
cardiac muscle
muscle contraction that shortens the muscle to move a load
concentric contractions
Ability to shorten (contract) forcibly
contractility
twitch contraction phase when tension increases
contraction phase
phosphagen used to store energy from ATP and transfer it to muscle
creatine phosphate
sarcoplasmic structure that attaches to the sarcolemma and shortens the muscle as thin filaments slide past thick filaments
dense body
to reduce the voltage difference between the inside and outside of a cell’s plasma membrane (the sarcolemma for a muscle fiber), making the inside less negative than at rest
depolarize
cell structure that anchors the ends of cardiac muscle fibers to allow contraction to occur
desmosome
muscle contraction that lengthens the muscle as the tension is diminished
eccentric contraction
ability to stretch and rebound
elasticity
loose, and well-hydrated connective tissue covering each muscle fiber in a skeletal muscle
endomysium
outer layer of connective tissue and skeletal muscle
epimysium
ability to undergo neural stimulation
excitability
sequence of events from motor neuron signaling to a skeletal muscle fiber to contraction of the fiber’s sarcomeres
excitation-contraction coupling
ability to lengthen (extend)
extendability
bundle of muscle fibers within a skeletal muscle
fascicle
muscle fiber that primarily uses anaerobic glycolysis
fast glycolytic (FG)
intermediate muscle fiber that is between slow oxidative and fast glycolytic fibers
fast oxidative (FO)
replacement of muscle fibers by scar tissue
fibrosis
anaerobic breakdown of glucose to ATP
glycolysis
modification of contraction strength
graded muscle response
process in which one cell splits to produce new cells
hyperplasia
abnormally high muscle tone
hypertonia
addition of structural proteins to muscle fibers
hypertrophy
abnormally low muscle tone caused by the absence of low-level contractions
hypotonia
part of the sarcolemma that connects cardiac tissue, and contains gap junctions and desmosomes
intercalated disc
muscle contraction that occurs with no change in muscle length
isometric contraction
muscle contraction that involves changes in muscle length
isotonic contraction
product of anaerobic glycolysis
lactic acid
subset of a cross-bridge in which actin and myosin remain locked together
latch-bridges
the time when a twitch does not produce contraction
latent period
sarcolemma of muscle fiber at the neuromuscular junction, with receptors for the neurotransmitter acetylcholine
motor end-plate
motor neuron and the group of muscle fibers it innervates
motor unit
force generated by the contraction of the muscle; tension generated during isotonic contractions and isometric contractions
muscle tension
low levels of muscle contraction that occur when a muscle is not producing movement
muscle tone
muscle-forming stem cell
myoblast
long, cylindrical organelle that runs parallel within the muscle fiber and contains the sarcomeres
myofibril
instrument used to measure twitch tension
myogram
protein that makes up most of the thick cylindrical myofilament within a sarcomere muscle fiber
myosin
fusion of many myoblast cells
myotube
synapse between the axon terminal of a motor neuron and the section of the membrane of a muscle fiber with receptors for the acetylcholine released by the terminal
neuromuscular junction (NMJ)
signaling chemical released by nerve terminals that bind to and activate receptors on target cells
neurotransmitter
amount of oxygen needed to compensate for ATP produced without oxygen during muscle contraction
oxygen debt
cell that triggers action potentials in smooth muscle
pacesetter cell
stem cell that regenerates smooth muscle cells
pericyte
connective tissue that bundles skeletal muscle fibers into fascicles within a skeletal muscle
perimysium
action of myosin pulling actin inward (toward the M line)
power stroke
product of glycolysis that can be used in aerobic respiration or converted to lactic acid
pyruvic acid
increase in the number of motor units involved in contraction
recruitment
period after twitch contraction when tension decreases
relaxation phase
plasma membrane of a skeletal muscle fiber
sarcolemma
longitudinally, repeating functional unit of skeletal muscle, with all of the contractile and associated proteins involved in contraction
sarcomere
age-related muscle atrophy
sarcopenia
cytoplasm of a muscle cell
sarcoplasm
specialized smooth endoplasmic reticulum, which stores, releases, and retrieves Ca++
sarcoplasmic reticulum (SR)
stem cell that helps to repair muscle cells
satellite cell
striated, multinucleated muscle that requires signaling from the nervous system to trigger contraction
skeletal muscle
muscle fiber that primarily uses aerobic respiration
slow oxidative (SO)
nonstriated, mononucleated muscle in the skin that is associated with hair follicles
smooth muscle
what does the smooth muscle assist with
moving materials in the walls of internal organs, blood vessels, and internal passageways
blocks of paraxial mesoderm cells
somites
relaxation of smooth muscle tissue after being stretched
stress-relaxation response
space between a nerve (axon) terminal and a motor end-plate
synaptic cleft
projection of the sarcolemma into the interior of the cell
T-tubule
a continuous fused contraction
tetanus
the thick myosin strands and their multiple heads projecting from the center of the sarcomere toward, but not all to way to, the Z-discs
thick filament
thin strands of actin and its troponin-tropomyosin complex projecting from the Z-discs toward the center of the sarcomere
thin filament
stepwise increase in contraction tension
treppe
the grouping of one T-tubule and two terminal cisternae
triad
regulatory protein that covers myosin-binding sites to prevent actin from binding to myosin
tropomyosin
regulatory protein that binds to actin, tropomyosin, and calcium
troponin
single contraction produced by one action potential
twitch
enlargement of neurons that release neurotransmitters into synaptic clefts
varicosity
smooth muscle found in the walls of visceral organs
visceral muscle
membrane proteins that open sodium channels in response to a sufficient voltage change, and initiate and transmit the action potential as Na+ enters through the channel
voltage-gated sodium channels
addition of successive neural stimuli to produce greater contraction
wave summation
