Human Respiratory Organs

• The human body can be divided into three regions.

  A) Head

  B) Thorax

  C) Abdomen

  
• As the air passes through the nasal cavity, the air is smelt, warmed, filtered and moistened slightly. The air meets at the pharynx, a junction at back of the oral cavity.
• The pharynx is a junction between two tubes. The air must travel down only one of these tubes. One is the windpipe (trachea) and the other is the gullet (oesophagus).

  A) trachea

  B) gullet

  
• Pharynx


  Passageway of both air and food.
• Epiglottis

  Covers larynx during deglutition.
• Larynx (Voice Box)


  Production of sound.
• Trachea (Windpipe)


  • The main airway.
  • Located in front of the neck.
  • Hard with tough and flexible C-shaped cartilage rings to keep it open all the time.
• Bronchi


  Branching airways
• Bronchioles


  Small bronchi.
• Lungs

  A) Trachea

  B) Bronchi

  C) Alveoli

  
• Throat

  A) Epiglottis

  B) Larynx

  C) Pharynx

  D) Mouth

  
• Nose and the Nasal Cavity

  • Provides airway
  • Moistens and warms air
  • Filters air (Hair)
  • Resonating chamber for speech
  • Olfactory receptors

  A) Nasal Cavity

  B) Pharynx

  C) Nose

  D) Mouth

  
• Lungs

  • The major organ for respiration.
  • Sponge-like organ that is rich in blood capillaries for gas exchange which occurs in the alveoli.

  A) Alveoli

  B) Trachea

  C) Bronchi

  D) Bronchole

  
• Alveoli 


  • Site for external respiration. (Exchange of O2 from the atmosphere to CO2 from the cell as waste product).
  • Surfactant.