Respiration L.1

• Respiration


  Provides energy for cellular metabolism
• Respiratory Structure


  • Large surface area for maximal oxygen and carbon dioxide exchange rate
  • Moist environment to dissolve oxygen and carbon dioxide
• Stages in Respiration


  1. Breathing-inspiration and expiration

  2. External respiration - exchange of gases between air and blood

  3. Internal respiration - exchange of gases between blood and body tissue

  4. Cellular respiration - energy releasing chemical reactions within the cell
• Respiratory Tract


  • Lungs are protected by bone and muscle of thoracic cavity
  • Respiratory tract is the passageway that moves air from external environment to respiratory surface
• Upper Respiratory Tract


  • Nasal passages
  • Pharynx (throat)
  • Epiglottis
  • Glottis
  • Larynx
• Nasal passages


  • Serve to warm, moisten, and clean incoming air via mucous and cilia, Coughing/Sneezing
• Larynx


  • Made of cartilage and contains vocal cords, air passes through to create sound
  • Longer cords = lower sound
  • Shorter cords = higher sound
• Trachea


  • Semicircular, cartilage arches prevent collapsing
• Lower Respiratory Tract


  • Bronchi
  • Bronchioles
  • Alveoli
• Bronchi


  • Branches from trachea that enter the left and right lung, have cartilage rings and mucous producing cells
• Bronchioles


  • Smaller branches within each lung, do not have cartilage rings
• Alveoli


  • Tiny sacs at the end of bronchioles for gas exchange with capillaries, walls are one cell thick
  • Lined with lubricating film (surfactant) that prevents them from collapsing/sticking together by reducing surface tension
• Right lung


  • Has 3 lobes
• Left lung


  • Has 2 lobes (to make room for the heart)
• Pleural Membrane


  • Thin, double layered membrane that surrounds each lung and connects lungs to body
  • Outer layer attaches to inside of chest wall
  • Inner layer attaches to lung
  • Fluid is between the 2 layers so that they stick to each other
  • Allows lungs to expand with thoracic cavity
• Path of air as it enters our bodies

  Nostrils -> Nasal passages -> Pharynx -> Epiglottis -> Glottis -> Larynx -> Trachea -> Bronchi -> Bronchioles -> Alveoli -> and back out again