Module 4 - MUSCLES

  1. What are the three types of muscle tissue?
    • skeletal
    • smooth
    • cardiac
  2. What does skeletal muscle consist of?
    long, multinucleate cells with cross striations.  We can consciously control the action of skeletal muscle so we call it voluntary muscle
  3. What does cardiac muscle consist of?
    It is found in the heart, has branched fibers with intercalated disks which mark the boundaries between cells.  This muscle is involuntary. 
  4. What does smooth muscle consist of?
    spindle shaped cells which surround tubes such as in the digestive system.  These cells have one nucleus and are involuntary. 
  5. Skeletal Muscle
    Muscle composed of cylindrical multinucleate cells with obvious striations; the muscles attached to the body's skeleton; voluntary muscle.
  6. What are the functions of muscle?
    • Movement
    • Posture maintenance
    • Joint stabilization
    • Heat Generation
  7. Movement
    Muscle contraction provides movement as in walking or eye movement.
  8. Posture Maintenance
    Contraction of muscle allows us to remain upright!
  9. Joint Stabilization
    Tendons of muscles often extend across joints and keep them stable.
  10. Heat Generation
    Muscle contraction produces heat used to maintain body temperature.
  11. What are some of the functional characteristics of muscle?
    • Excitability
    • Contractility
    • Extensibility
    • Elasticity
  12. Muscle Excitability
    refers to the ability to respond to stimuli which in muscle is usually a neurotransmitter released by a nerve cell.  This chemical gives the muscle cell the “message to contract”.
  13. Muscle Contractility
    refers to the ability of a muscle cell or fiber to shorten producing movement. This property sets muscle apart from other tissues
  14. Muscle Extensibility
    refers to the ability of muscle fibers to be stretched or extended.
  15. Muscle Elasticity
    refers to the ability of muscle fibers to contract or extend and return to their original length.
  16. What are the primary functions of muscle?
    • Producing movement
    • Maintaining posture
    • Stabilizing joints
    • Generating heat
  17. What percentage of body mass is skeletal muscle?
  18. What are some additional functions of muscle?
    • Protection of the more fragile internal organs (viscera).
    • Smooth muscles form valves to regulate passage of substances through internal body openings
    • Dilates and contracts the pupils of the eye
    • Forms arrector pili muscles attached to hair follicles
  19. What are some key words to remember for cardiac muscle?
    • cardiac
    • striated
    • involuntary
  20. What are some key words to remember for skeletal muscle?
    • skeletal
    • striated
    • voluntary
  21. What are striations?
    Obvious stripes within the muscle cells.
  22. What are some key words to remember for smooth muscle?
    • visceral
    • nonstriated
    • involuntary
  23. Epimysium
    Sheath of fibrous connective tissue surrounding a muscle. Means literally 'outside the muscle'.
  24. Fascicle
    Bundle of nerve or muscle fibers bound together by connective tissue. Resembles bundles of sticks. Means 'bundles'.
  25. Perimysium
    Connective tissue that bundles muscle fibers into fascicles. Means 'around the muscle [fascicles]'
  26. Endomysium
    Thin connective tissue surrounding each muscle cell. Means 'within the muscle'.
  27. Insertion
    Movable attachment of a muscle.
  28. Origin
    Attachment of a muscle that remains relatively fixed during muscular contraction.
  29. Direct muscle attachment
    Also known as fleshy attachments. Epimysium of the muscle is fused to the periosteum of a bone or perichondrium of a cartilage.
  30. Indirect muscle attachment
    Where the muscle's connective tissue wrappings extend beyond the muscle either as a ropelike tendon or as a sheetlike aponeurosis.
  31. Aponeurosis
    Fibrous or membranous sheet connecting a muscle and the part it moves.
  32. Tendon
    Cord of dense fibrous tissue attaching muscle to bone.
  33. Which type of muscle attachment is more common?
    Indirect muscle attachment is more common than direct muscle attachment.
Card Set
Module 4 - MUSCLES