Function of the Respiratory System  Trap irritants / infectious particles  Moistens and warms incoming air  Breathing process  Oversees gas exchanges Exchange O 2  Air to blood & Blood to cells Exchange CO 2  Cells to blood & Blood to air  Exchange of gasses takes place within the lungs in the alveoli  Enable speech production

Organs of the Respiratory system  Nose  Pharynx  Larynx  Trachea  Bronchi  Lungs – alveoli

Upper Respiratory Tract

Anatomy of the Nasal Cavity  Nose is primary passageway for air entering respiratory system  Nasal septum : divides cavity into right & left halves  The cavity is lined with respiratory mucosa  Moistens air  Traps incoming foreign particles  Lateral walls have projections called conchae  Increases surface area  The nasal cavity is separated from the oral cavity by the palate  Anterior hard palate (bone)  Posterior soft palate (muscle)

Respiratory Tree Divisions  Primary bronchus  Secondary bronchus  Tertiary bronchus  Bronchiole  Terminal bronchiole

Bronchioles & Alveoli  Smallest branches of the bronchi  Terminal bronchioles end in alveoli  Structure of alveoli  Alveolar duct  Alveolar sac  Alveolus