Skeletal Muscle Physiology Flashcards
skeletal muscle
cylindrical and very long, striated, not branched, multinucleate, and controlled by the somatic nervous system
Smooth muscle
spindle shaped and short, not striated or branched, single nucleus, controlled by autonomic nervous system
Muscle Tissue
1 main task: convert chemical energy from ATP to the mechanical energy of motion
functions of muscles
movement, stability, control, and heat production
movement
whole body, individual parts, and body contents
stability
maintain posture, resist gravity, and stabilize joints
control
muscles control body openings and passages
heat production
skeletal muscles produce up to 85% of body heat
myofibril
an organelle found in skeletal muscle cells, responsible for contraction. arranged around axis of muscle fiber and fill the sarcoplasm
sarcomere
repeating units that make up the myofibril, could contain up to 10,000 sarcomeres
sarcoplasmic reticulum
smooth endoplasmic reticulum that wraps around the myofibril and stores Ca(2+)
terminal cisternae
enlarged areas of the sarcoplasmic reticulum, 1 transverse tubule lies btwn two terminal cisternae
transverse tubule
tunnel of the sarcolemma that encircle the myofibrils
triad
composed of one t-tubule that lies btwn 2 terminal cisternae
nuclei
located peripherally in skeletal muscle fibers, just beneath the sarcolemma
sarcoplasm
the name given to the cytoplasm of a muscle fiber
sacrolemma
the name given to the plasma membrane of a muscle fiber
muscle fiber
muscle cell
endomysium
sheath of loose areolar connective tissue around each muscle fiber
fascicle
subsection with the whole muscle composed of a bundle of muscle fibers
perimysium
sheath of a connective tissue that covers each fascicle
epimysium
connective tissue that covers the entire muscle, they blend into tendons and enclose fascicles