Muscle tissue

• Muscle Tissue

  Composed of cells that optimize the universal cell property of contractility (Actine thin & miosin filaments thick)

  
• Muscle Tissue


  • Ability to move
• Function Characteristics of Muscle Tissue

  • Excitability/Irritability
  • Contractility
  • Extensibility
  • Elasticity

  
• Excitability/Irritability


  Plasma membrane emits electrical impulses
• Extensibility


  Ability of the muscle to extend
• Elasticity


  Ability of the muscle to stretch
• Three types of muscle tissue

  • Striated/Skeletal Muscle Tissue
  • Smooth Muscle Tissue
  • Cardiac Muscle Tissue

  
• Striated/Skeletal Muscle Tissue


  • Also known as STRIATED
  • Made up of skeletal muscle fiber
  • Made up of satellite cells
  • Allows for quick and forceful voluntary movements

  
• Myofibril


  1. Made up of myosin & actin

  2. Thin (actin) filaments – to glide above the thin filament

  3. Thick myosin filaments- found on the A band

  4. Sarcoplasmic reticulum- basic unit of contraction for the whole myofibril

  5. I Band – light in color, isotopic, properly arranged

  6. A band – dark in color, anisotropic, different direction
• Sarcomere


  Basic unit of contraction of the myofibril
• Three layers of Myofibril

  • Epimysium
  • Perimysium
  • Endomysium
• Epimysium

  Outer layer, dense connective tissue that surrounds the entire muscle fiber

  
• Perimysium


  Spaces in between the myofibril, thin connective layer that surrounds each bundle of myofibril
• Endomysium


  Main cover of myofibril, very thin layer of reticular fibers that surrounds myofibril
• Smooth Muscle Tissue


  • Specialized for slow and long lasting prolonged contraction
  • Filled with actin & myosin
  • Involuntary movement
  • Independent on neural enervation
• Three types of smooth muscle

  • Visceral smooth muscle
  • Vascular smooth muscle
  • Smooth muscle of the Iris
• Cardiac Muscle Tissue


  • Forms the atria & the ventricle of the heart
  • Work to keep our heart by pumping
  • True involuntary movement
• Two major parts of Cardiac Muscle Tissue

  • Intercalated disc
  • Gap junction
• Intercalated disc


  Small connections between two cardiac cells
• Gap junction


  Transfers stimulation from one cardiac cell to another, sends signals to one myocyte to two myocyte
• Purkinje fiber


  Fibers in cardiac muscle tissue, fiber that makes up the fiber tissue

  
• Pacemaker cells


  Control the contraction of heart, located in heart