MUSCLE Flashcards
this is the functional unit of muscle composed of overlapping thick and thin filaments anchored in characteristic arrangement?
sarcomere
thick filament
myosin
thin filament
f-actin
A band
actin and myosin
I band
actin only
M line
myosin and binding protein
H zone
myosin only
Z line
binding protein
the Z line of the I band in embedded where in the sarcomere?
A band
T/F, muscle fiber is the muscle cell?
T
how is muscle cell formed?
fusion of many myoblasts into tubes
what part of the skeletal muscle contains the contractile protein?
myofibrils
in terms of muscle growth, all muscles can do this?
hypertrophy
not significant in skeletal or cardiac muscle but smooth muscle retains the capacity to do this?
hyperplasia
this is the change to a different form?
metaplasia
plasmalemma?
sarcolemma
ER sequesters the Ca
sarcoplasmic reticulum
terminal storage areas of SER
terminal cisternae
invaginations of sarcolemma spec for rapid depolarization into fiber
transverse tubule
why is calsequestrin important?
for binding of calcium in the terminal cisterna
this blocks the binding sites on actin for myosin?
tropomyosin
calcium released from the sarc reticulum that binds to this?
troponin
contraction is all or none or graded?
all or none
one nerve and all fibers supplied
motor unit
myoneural jct
motor end plate
sensory input to CNS to monitor and adjust stretch and contraction
neuromuscular spindles
monitor stretch in tendons
neurotendinous endings
point where motor nerve pierces the epimysium
motor point
describe the red fibers?
small diameter, much myoglobin, little glycogen, many mitochondria
describe the white fibers?
much glycogen, fewer mitochondria, little or no myoglobin, larger diameter
covering around each muscle fiber?
endomysium
covering the individual bundles of muscle fibers
perimysium
covering of the entire muscle?
epimysium
T/F, striated muscle doesn’t need extracellular calcium for contraction like smooth muscle?
T
of the skeletal muscle fibers which is the fastest? what is type I, IIa
type IIb, white fibers
red fibers
intermediate fibers
in skeletal muscle fiber, when you see a red stain, what is this?
glycogen, so white fibers
what is significant about the muscle spindle apparatus?
sensory
smiliar to Golgi tendon organ that processes information about the state of stretch of the tendons
alpha motor neurons are sensory or motor?
motor
gamma motor neurons are sensory or motor?
sensory
T/F, cardiac muscle is a true structural syncytium but acts like a functional one due to intercalated discs?
F, it is not
which muscle type has branching?
cardiac muscle
how to correctly ID the cardiac muscle?
centrally located nuclei, intercalated discs, striations
where do the T tubules meet in the heart and skeletal muscles?
Z line
A-I junction
what is the arrangement of the t tubules in the cardiac and skeletal muscle?
dyad
triad
how is atrial muscle different from ventricular muscle?
smaller diameter, fewer terminal cisternae, more t-tubules and releases ANP
what is ANP?
atrial natriuretic polypeptide and is used as a diuretic and vasodilator
what are conduction fibers?
SA, VA, bundle of HIS and purkinje fibers
less like muscle and more non contractile cells, not specialized for contraction as much as condition of ions
what is noticeable in the aging heart?
lipofuscin
calcium crystals
