Muscular system Flashcards
Prefixes myo and mys refer to
Muscle
Prefix sarco refers to
Flesh
Attached to bones, facial muscle
Skeletal muscle
Wall of heart
Cardiac muscle
Hallow visceral organ and its single nucleus
Smooth muscle
Muscle cell
Muscle fiber
have visible banding
Striated
Enclose single muscle fiber
Endomysium
wraps around a fascicle
(bundle) of muscle fibers
Perimysium
Cover the entire skeletal muscle
Epimysium
Cord like structure
Tendons
Sheet like structure
Aponeurosis
Specialized plasma membrane
Sarcolemma
Long organelles inside muscle cell
Myofibrils
specialized
smooth endoplasmic reticulum
Sarcoplasmic reticulum
light band
Contains only thin filaments
I band
dark band
Contains the entire length of the thick filaments
A band
contractile unit of a
muscle fiber
Sarcomere
Thick filaments
myosin filaments
Thin filaments
actin filaments
Composed of the protein myosin
Has ATPase enzymes
Myosin filaments have heads (extensions, or cross
bridges)
Myosin and actin overlap somewhat
myosin filaments
Composed of the protein actin
Anchored to the Z disc
actin filaments
Stores and releases calcium
Surrounds the myofibril
Sarcoplasmic reticulum (SR)
ability to receive and respond to a
stimulus
Excitability
ability to shorten when an adequate
stimulus is received
Contractility
ability of muscle cells to be stretched
Extensibility
ability to recoil and resume resting
length after stretching
Elasticity
one motor neuron and all the
skeletal muscle cells stimulated by that
neuron
Motor unit
Association site of axon
terminal of the motor neuron
and muscle
Neuromuscular junction
Gap between nerve and muscle
Nerve and muscle do not make
contact
Area between nerve and muscle
is filled with interstitial fluid
Synaptic cleft
chemical released by nerve
upon arrival of nerve impulse
Neurotransmitter
The neurotransmitter for skeletal muscle is
acetylcholine (AcH)
Sarcolemma becomes permeable to
sodium
(Na+)