Histology Muscle Tissues Flashcards
Function of muscles
Contract/get smaller, cannot force themselves to get bigger, but can be stretched.
Skeletal muscle
Syncytium/multi nucleated. Attached to bone, antagonists that work together
Cardiac muscle
individual nucleus in center of cell
Smooth muscle
fusiform (tapered at ends)
Striated muscles
Skeletal and cardiac, voluntary contraction
Non-striated muscles
Involuntary, Smooth muscles
Protoplasm eq (cytoplasm, nucleus, organelles)
Sacroplasm
Plasmalemma eq (plasma membrane)
Sacrolemma (membrane wrapping each muscle cell)
Smooth ER eq
Sarcoplasmic Reticulum
Mitochondria eq
Sarcosomes
Muscle Cell
Myofiber
Sarcomere
Linear subunit
Striated muscle layout from epimysium to myofiber
muscle fiber surrounded by endomysium, groups of muscle fibers surrounded by perimysium, group of muscle fibers called fascicle. Epimysium surrounds whole tissue.
Striated muscle layout from myofiber to sarcomere
Myofibrils make up a myofiber. Light areas are I band, dark areas are A band. Middle of I band is dark line called Z line where actin filaments meet.
T tubules in striated muscle cells
Carry electric signals from the surface into and around myofibrils. Causes release of calcium from the SR triggering contractions
Cardiac muscle components
Everything skeletal muscle has + intercalated discs (desmosomes, gap and tight junctions), individual cells with central nucleus, branched
Smooth muscle characteristics
Single central nucleus, interconnected by gap junctions, fusiform cells, External lamina on outer surface (like basal lamina)
Contraction of smooth muscle
Myosin is at junctions, elongated nucleus forms corkscrew
smooth muscle layers
Circular layer (muscle in long section) and longitudinal layer (muscle in cross section)
