Essentials of Anatomy and Physiology

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CHAPTER 7

Chapter Outline

Muscle Structure
Muscle Arrangements
Antagonistic muscles
Synergistic muscles
The Role of the Brain
Muscle Tone
Exercise
Muscle Sense
Energy Sources for Muscle Contraction
Muscle Fiber—Microscopic Structure
Sarcolemma—Polarization
Sarcolemma—Depolarization
Contraction—The Sliding Filament Mechanism
Responses to Exercise—Maintaining
Homeostasis
Aging and the Muscular System
Major Muscles of the Body
Muscles of the Head and Neck
Muscles of the Trunk
Muscles of the Shoulder and Arm
Muscles of the Hip and Leg

BOX7–1 ANABOLIC STEROIDS

BOX7–2 TETANUS AND BOTULISM

BOX7–3 MUSCULAR DYSTROPHY

BOX7–4 MYASTHENIA GRAVIS

BOX7–5 COMMON INJECTION SITES

Student Objectives

• Name the organ systems directly involved in
  movement, and state how they are involved.


• Describe muscle structure in terms of muscle cells,
  tendons, and bones.


• Describe the difference between antagonistic and
  synergistic muscles, and explain why such arrange-
  ments are necessary.


• Explain the role of the brain with respect to skele-
  tal muscle.


• Define muscle tone and explain its importance.


• Explain the difference between isotonic and iso-
  metric exercise.


• Define muscle sense and explain its importance.


• Name the energy sources for muscle contraction,
  and state the simple equation for cell respiration.


• Explain the importance of hemoglobin and myo-
  globin, oxygen debt, and lactic acid.


• Describe the neuromuscular junction and state the
  function of each part.


• Describe the structure of a sarcomere.


• Explain the following in terms of ions and charges:
  polarization, depolarization, and repolarization.


• Describe the sliding filament mechanism of mus-
  cle contraction.


• Describe some of the body’s responses to exercise
  and explain how each maintains homeostasis.


• Learn the major muscles of the body and their
  functions.