Skeletal System

• Anatomy


  Science of structure
• Physiology


  Science of function
• Structure


  Determines Function
• Function


  Modifies Structure
• Attachment of muscle


  Determines function - origin + insertion
• Cortical bone


  Hard bone
• Trabecular bone


  Spongy bone
• Organization of the body


  • Cell
  • Tissues
  • Organs
  • Systems
• Cell


  Basic structural unit
• Tissues


  Group of cells with common function
• Organs


  Group of tissue that perform a function
• Systems


  Complex systems: organs that function together
• Homeostasis


  Constant balance in the body
• Cell membrane


  Thin, elastic, has small pores allowing certain movement, boundary that determines what gets in and out
• Cytoplasm


  Contains cytosol + organelles, where basic chemical reactions occur
• Mitochondria


  Powerhouse, has enzymes
• Nucleus


  Controls all chemical reactions and all body functions
• Cells are specialized but have some similar structure</b>
• Organelles


  • Lysomes: digestion
  • Golgi apparatus: protein synthesis
  • SER + RER: Synthesize protein + cholesterol
• Histology


  Study of tissues
• 4 basic types of tissues


  • Epithelial
  • Muscle
  • Nervous
  • Connective
• Epithelial tissue


  Covering/lining tissue, cells very close together with little space between, cover body surfaces, line body cavities, form the inner coat of blood vessels, form glands
• Connective tissue


  Connects and supports, highly vascular and well nourished
• Types of connective tissue


  • Mesenchymal: embryonic
  • Connective tissue proper: resists being pressed and pulled apart
• Ground substance


  Loose matrix, determines compressive strength, traps water, can be fluid or a stiff hydrated gel
• Fibers


  Embedded in ground substance, determine tensile strength
• Types of fibers


  • Collagen: most abundant, largest, greatest stress resisters, very flexible
  • Elastic: composed of elastin, recoil to original shape
  • Reticular: help form networks, common in lymph nodes
• Loose connective tissue


  Watery, contains all 3 fiber types haphazardly arranged, can't stand tensile stress
• Dense irregular connective tissue

  Has collagen, can stand more tensile stress
• Fascia


  Delineates structure, can help reduce infection, binds to underlying skin and muscle, easy to move
• Dense regular connective tissue


  Parallel arranged collagen fibers
• Dense elastic connective tissue


  Very stretchy
• Other forms of connective tissue


  • Cartilage
  • Blood
  • Bone
• Axial skeleton


  Skull, ribs, sternum, vertebrae - everything except extremities
• Appendicular skeleton


  Appendages and skeleton
• Fabella


  204th bone, cause of knee pain and osteoarthritis
• 5 ways the skeletal system serves the body

  • Supports surrounding tissue
  • Protects vital organs
  • Makes up a system of levers that operate muscles
  • Manufacturing of red blood cells
  • Provide storage for minerals
• As aging occurs, RBC production and fat cells decrease
• Functions of bones in sports medicine


  • Serve as points of attachment for muscles and ligaments
  • Enter in formation of joints
  • Serve as landmarks for body measurements
  • Frequent site of movement injuries
  • Important variables in movement performance
• Bone classifications


  • Long bones: 2 ends and a shaft
  • Short bones: 3 equal dimensions
  • Flat bones: no articular surface
  • Irregular bones: irregular shaped
  • Sesamoid bones: small, rounded, enclosed in tendons