Microscopic anatomy doover Flashcards
surrounds entire muscle, dense irregular connective tissue
Epimysium
Dense irregular tissue surrounding fasciles
Perimysium
Fine areolar connective tissue, surrounds individual muscle fibers
Endomysium
cytoplasm of muscle cell contains glycosomes and myoglobin
Sarcoplasm
stores glycogen that provide glucose during muscle cell activity for ATP production
Glycosomes
red pigment that stores oxygen
myoglobin
repeating bands of light and dark bands (striations) within sarcoplasm
Myofibrils
between z disc, functional unit of skeletal muscle
Sarcomere
muscle equivalent of actin-myosin
Myofilament
during contraction, globular heads of thick filament link thick and thin filaments together
Cross bridges
When an electrical impulse passes by, t tubule proteins change shape, causing SR proteins to change shape, causing release of Ca into cytoplasm
Triad relationship
myosin, double globular head, extend entire length of A band and connect at M line
Thick filaments
actin, extend across I band and half in A band, contain troponin and tropomyosin
Thin filaments
protein that spirals around actin to stabilize and stiffen. In a relaxed muscle, they block myosin-binding sites
Tropomyosin
protein that inhibits actin binding. Binds to tropomyosin and binds calcium molecules.
Troponin
Protein that anchors thick filament to z disc, stabilize thick filament, prevents over stretching
Titin
link thin filaments to integral proteins of sarcolemma
Dystrophin
Part of sarcoplasm, surrounds each myofibril, communicate at H zone, regulars intracellular levels of ionic calcium. Stores calcium and releases on demand of muscle fiber contraction
Sarcoplasmic reticulum
Part of sarcoplasm, A Band- I band junction, increase surface area, run along paired terminal cisterns of SR. Triads encircle each sarcomere, conduct impulses to deepest region of muscle cell and every sarcomere, signal release of calcium
T-tubules
