Musculoskeletal System Flashcards
Lacks striation
Cells are much smaller, tapering strands, with a single, centrally-located nucleus
Responsible for peristalsis, propelling, and regulating movement of substance
Contractions are involuntary and unconscious
Smooth Muscle
✓ Striated involuntary muscle
✓ Found in the heart
✓ With presence of intercalated discs
Cardiac Muscle
✓ Voluntary contractions
✓ Attached to and interacts with skeletal elements
✓ Striated muscle
Skeletal Muscle
✓ Actin and myosin filaments slide past each other longitudinally
✓ “Head” of myosin binds to an actin filament, forming a cross-bridge and pulls the thin filament toward the center of the sarcomere
Sliding Filament Theory
outermost tissue of muscles, surrounds the whole muscle
epimysium
multiple bundles of muscle fibers in the epimysium
Fascicle
tissue that surrounds every fascicle
Perimysium
Inner most connective tissue in the fascicle, and covers every muscle fiber
endomysium
functional unit of a muscle
sarcomere
borders the sarcomere
z lines
each of the sarcomere is made up of this
myofibrils
filaments inside ether myofibrils
actin filaments
filaments attached to the z line
actin filaments
filaments found in the middle of the sarcomere
myosin filaments
band where the myosin filament is located
A band
band where the actin filaments can be found
I band
Bind to actin strands when a muscle fiber is at rest
Prevents the actin and myosin from interacting
Tropomyosin and troponin complex
For a muscle fiber to contract, what should you do?
the myosin-binding sites must be uncovered
In ________, each motor neuron may synapse with multiple muscle fibers
vertebrates