The Respiratory System

The Respiratory System

1. The 5 functions of the Respiratory System

   • Sound
   • Smell
   • Protection
   • Exchange of Gases
   • Air Movement

2. Structures of the Respiratory Tract

   • Upper Respiratory Tract
     • Nasal Cavity
     • Pharynx
       • Nasopharynx
       • Oropharynx
       • Laryngopharynx
     • Larynx - Voice Box
       • Epiglottis
       • Thyroid Cartilage
       • Cricoid Cartilage
     • Nose
   • Lower Respiratory Tract
     • Trachea
       • Walls supported with tracheal cartilage
         • incomplete C-shaped cartilage
         • Strengthen & Protect Airway
     • Bronchi
       • Right Primary Bronchus
         • Supplies right lung
         • Larger, steeper angle
       • Left Primary Bronchus
         • Supplies Left lung
       • Secondary Bronchi
         • Tertiary Bronchi
           • Bronchioles
             • Alveoli
               • 150 million
               • Spongy airy appearnce
               • Vastly increased surface area 140m^2
                 • For extensive, rapid gas diffusion
               • Pneumocyte 1
               • Pneumocyte 2
                 • Surfactant
                   • Oily secretion that reduces surface tension of alveoli & keep it open
             • no cartilage
             • Smooth muscle

3. Functional Zones

   • Conducting Portions
     • Nose, Pharynx, Larynx, Trachea
       • Air is filtered, warmed and humidified
       • Lined with respiratory Mucosa with Cilia
         • Pseudostratified Columnar Epithelia
   • Respiratory Portion
     • Small bronchioles and Alveoli
       • Where gas exchange occurs

4. Lungs

   • Left Lung
     • 2 lobes
       • Superior
       • Inferior
   • Right lung
     • 3 Lobes
       • Superior
       • Middle
       • Inferior
   • Pleura
     • Visceral Pleura
     • Parietal Pleura
       • When punctured
         • Pneumothorax
     • Pleural Fluid
       • Reduces friction & lubricates space between the two pleural areas