10 and 11 Flashcards
what are the functions of skeletal muscle
Produce movement, maintain posture and body position, support soft tissue, guard body entrances and exits, maintain body temperature, store nutrients
what are layers of connective tissue
Epimysium, perimysium, endomysium
what is the definition of tendon
Collagenous band that connects a skeletal muscle to and element of the skeleton
what is the definition of ligament
Dense band of connective tissue fibers that attaches one bone to another
why does skeletal muscle have multiple nuclei
Multinucleate
actin is responsible for
thin filaments
myosin is responsible for
thick filaments
roles of actin in contraction and relaxation
pulled towards the centers of the sarcomeres, pulled away from the centers of the sarcomeres
roles of myosin in contraction and relaxation
pull the thin filament towards the center of sarcomere, pull thin filament away from the center of sarcomere
Z line
Bisect I Band, consist of actins
M line
Subdivision and center of A band, help stabilize positions of thick filaments
H band
Subdivision of A band, on either side of the M line, contains thick filaments
A band
Contains thin and thick filaments
I band
Contains thick filaments
Path of action potential
Depolarization and repolarization events produce an electrical impulse
What is a single motor neuron with all the muscle fibers it innervates called.
motor neurons
concentric
tension remains constant but the muscle shortens
eccentric
tension remains constant but the muscle lengthens
isotonic
tension increases but the skeletal muscle shortens
isometric
tension rises but muscle length stays the same
What can a mitochondria supply at peak levels of muscle exertion?
1/3 of ATP needs
Parallel
fascicles are parallel to the long axis of the muscle
Circular
fascicles are concentrically arranged around and opening
Pennate
fascicles form a common angle with the tendon
Convergent
fascicles extending over a broad area coming together on a common attachment site
Antagonistic
opposing movement of agonist
Agonist/Prime mover
responsible for a specific movement
Synergist
helps larger agonist work efficiently
The names of the muscles can indicate what?
position, direction, fascicle arrangement, structural characteristics, action
Terms for muscle actions
abductor, adductor, depressor, extension, flexor, levator, pronator, supinator, tensor
internus/profundus
deeper muscles
externus
muscles visible at body surface
