Body Support and Movement

• The muscular and skeletal systems provide support to the body and allow for a wide range if movement.
• Hydrostatic Skeleton - Is a skeleton formed by a fluid-filled compartment within the body, called the Coelom.

   
• Exoskeleton - An external skeleton that consists of hard encasement on the surface of an organism.
• Endoskeleton - A skeleton that consists of hard, mineralized structures located within the soft tissue of organs.
• Cardiac Muscles - Found only in heart and are involuntary.
• Smooth Muscles - Found in walls of hollow organs such as stomach, intestines, blood vessels, uterus, etc.
• Skeletal Muscles - voluntary muscles and is long and cylindrical in appearance.
• The human skeleton is an endoskeleton that consists of 206 bones in the adult. It has five main functions:

  
  

  1.providing support to the body

  2. storing minerals and lipids

  3. producing blood cells

  4. protecting internal organs

  5. allowing for movement
• The body contains three types of muscle tissue: skeletal muscle, smooth muscle, and cardiac muscle.
• Myofibrils contain repeating units called sarcomeres, which consist of thick (myosin) and thin (actin) filaments arranged in parallel.
• Sarcolemma - is the site of action potential conduction, which triggers muscle contraction.
• The plasma membrane of a skeletal muscle fiber is called the sacrolemma.
• Each skeletal muscle fiber is a skeletal muscle cell.
• Muscle cells are specialized for contraction.