Chapter 8.pptx - Florida Gulf Coast University College of...

This preview shows page 1 - 17 out of 95 pages.

Florida Gulf Coast UniversityCollege of Health Professions & Social WorkDepartment of Rehabilitation SciencesAnatomy & Physiology I
Chapter 8Muscle Tissue
THREE TYPES OF MUSCLE TISSUESmooth muscle tissue:The oldest muscle tissueIn the walls of hollow organs, e.g., stomach, urinary bladder, and airwaysNot striatedInvoluntary
THREE TYPES OF MUSCLE TISSUESkeletal muscle tissue:Attached to bones and skinStriated Voluntary (i.e., conscious control)Fast & Powerful
THREE TYPES OF MUSCLE TISSUECardiac muscle tissue:Found only in the heart Striated Involuntary
THREE TYPES OF MUSCLE TISSUESmooth muscleSkeletal muscleCardiac muscle
SPECIAL CHARACTERISTICS OF MUSCLE TISSUEExcitability(responsiveness or irritability): Ability to receive and respond to stimuliContractility: Ability to shorten when stimulatedExtensibility: Ability to be stretched Elasticity: Ability to recoil to resting length
MUSCLE FUNCTIONS1.Movement of bones or fluids (e.g., blood)2.Maintaining posture and body position 3.Stabilizing joints4.Heat generation (especially skeletal muscle)
SKELETAL MUSCLEConnective tissue sheaths of skeletal muscle:Epimysium: dense regular connective tissue surrounding entire muscle Perimysium: fibrous connective tissue surrounding fascicles (groups of muscle fibers)Endomysium: fine areolar connective tissue surrounding each muscle fiber
BonePerimysiumEndomysiumMuscle fiberFascicle (with perimysium)EpimysiumTendonEpimysiumMuscle fiberin middle ofa fasciclePerimysiumEndomysiumFascicle
SKELETAL MUSCLE: ATTACHMENTSMuscles attach:Directly- epimysium of muscle is fused to the periosteum of bone or perichondrium of cartilageIndirectly- connective tissue wrappings extend beyond the muscle as a ropelike tendonor sheetlike aponeurosis
MICROSCOPIC ANATOMY OF A SKELETAL MUSCLE FIBER/CELLCylindrical cell 10 -100 m in diameter, up to 12 inches longMultiple peripheral nucleiMany mitochondriaGlycosomesfor glycogen storage, myoglobinfor O2storageSarcolemma= plasma membraneSarcoplasmicreticulum(SR) = endoplasmic reticulum
MYOFIBRILSDensely packed, rodlike elements ~80% of cell volume Exhibit striations: perfectly aligned repeating series of dark A bands and light I bandsI bandA band
SARCOMERESmallest contractile/functional unit of a muscle fiberThe region between two successive Z discsComposed of thickand thin myofilaments made of contractile proteins
FEATURES OF A SARCOMEREZ disc: coin-shaped sheet of proteins that anchors the thin filaments and connects myofibrils to one anotherH zone: lighter midregion where filaments do not overlap M line: line of protein myomesinthat holds adjacent thick filaments togetherThick filaments: run the entire length of an A bandThin filaments: run the length of the I band and partway into the A band
FEATURES OF A SARCOMEREI bandA bandH zoneZ diskM lineA band H zone M line I band

Upload your study docs or become a

Course Hero member to access this document

Upload your study docs or become a

Course Hero member to access this document

End of preview. Want to read all 95 pages?

Upload your study docs or become a

Course Hero member to access this document

Term
Spring
Professor
routor

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture