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Skeletal Muscle Structure. Basic Structure. This stuff is easy!. Each skeletal muscle is an organ composed mainly of skeletal muscle cells and connective tissue Tendons – connect Muscle to Bone Most skeletal muscles extend from one bone across a joint to another bone Muscles PULL!.
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Basic Structure This stuff is easy!
Each skeletal muscle is an organ composed mainly of skeletal muscle cells and connective tissue • Tendons – connect Muscle to Bone • Most skeletal muscles extend from one boneacross a jointto another bone • MusclesPULL!
Skeletal Muscle is composed of 3 parts • Origin • Attachment to the bone thatREMAINS STATIONARY or fixedwhen movement occurs • Insertion • Point of attachment to the bonethat moves when a muscle contracts • Body • Main part of the muscle / bulk
Tendons • Connect Muscle to Bone • STRAIN when injured • NOT to be confused with a Ligament • Connects Bone to Bone at a Joint -SPRAIN • Strong • Some Elasticity • Enclosed in synovial tubes • Lubricant • Tendon Sheaths
Bursae • Small synovial-lined sacs containing synovial fluid • Located between tendons and bone at joint • Reduce Friction with movement
Microscopic Structure of Muscle Fibers It really is like String Cheese
Contractile cells /FIBERS grouped into bundles • Each Fiber is wrapped by theEndomysium
Each Bundle isaFascicle • Each Fascicle is wrapped by thePerimysium • All bundles are wrapped by theEpimysium
The WHOLE Package of muscle is encased by theFasciaan non-elastic protective tissue
Fibers contain two types ofmyofilaments • Thick • Contain the proteinMYOSIN • Thin • Contain the proteinACTIN
Sarcomeres separated from each other by dark bands called Z LINES