Muscle Intro

1
Muscle Intro

• Functions of muscles
• Movement respiration, circulation, defecation
• Stability resists gravity and provides tension
  to tendons
• Communication
• Heat Production muscle provides 85 of body heat

2
Connective Tissue

• Think of connective tissue as the wrapping that
  holds muscle bundles together and separates them
• Endomysium thin layer that surrounds each muscle
  cell(fiber) makes room for capillaries and nerve
  fibers
• Fascicles bundles of muscle cells that appear as
  grain to the naked eye

3
Connective Tissue

• Perimysium A thick connective layer that
  surrounds each fascicle.
• Epimysium/Deep Fasciae a layer that surrounds
  each muscle
• Superficial fascia the layer of connective
  tissue between the muscle and skin, can be fatty

4
Anatomy of Muscles

• Origin a relatively stationary attachment
• Belly thick midregion of muscle
• Insertion a relatively mobile attachment
• Fusiform muscle thick in the middle thin at ends
  (biceps brachii)
• Parallel muscles straplike muscles uniform with
  parallel fascicles (sartorius)

5
Anatomy of Muscles

• Convergent muscles Fan-shaped, broad at origin,
  narrower at insertion
• Pennate muscles feather-shaped, fascicles run
  obliquely to a tendon that runs the length of
  muscle
• Circular muscle Sphincters (eyelids, anus)

6
Coordinated Action

• Prime mover muscle that produces most force
  during movement
• Synergist a muscle that aids the prime mover
• Antagonist muscle that resists the prime mover
  controlling rate of movement
• Fixator muscle that prevents a bone from
  moveing, holds steady