Upper Respiratory Tract

Upper Respiratory Tract

1. Nose

   • Hyaline Cartilage
   • DICT
   • Lateral Cartilages (One Pair)
   • Alar Cartilages (2 Pair)
   • Nostrils (Nares)

2. Nasal Cavity

   • Choanae (Paired)
     • Pharynx
       • ~13 cm length
       • Nasopharynx
         • Pseudostratified ciliated columnar epithelium
         • Everything other than food is blocked by the soft plate (elevates)
         • Auditory tubes: connect to middle ear - equalize pressure
         • Pharyngeal Tonsil -- enlarged = adenoids
           • helps to prevent the spread of infection.
       • Oropharynx
         • Immediately posterior to oral cavity - extends from soft palate superiorly to hyoid bone inferiorly
         • Palatine Tonsils - lateral walls of oropharynx
         • Lingual Tonsils - base of tongue
         • Common passageway for food
       • Laryngopharynx
         • Located posterior to larynx
         • Common passageway for food and air
         • Nonkeratinized stratified squamous epithelium
     • Superior
     • Middle
     • Inferior
     • Nasal Meatus: Separate ocnchae (immediately inferior to corresponding nasal concha
   • Floor
     • hard and soft palate
   • Roof
     • Nasal
     • Frontal
     • Ethmoid
     • Sphenoid
   • Septum
     • Divides nasal cavity into L and R portions
     • Formed with Septal Nasal Cartliage
   • Divided into three parts
     • Nasal Vestibule
       • Immediately Internal to nostrils
       • Lined with Vibrissae to trap large particulates
     • Olfactory Region
       • Superior Portion
       • Contains: olfactory epithelium
       • Helps detect different odors
     • Respiratory Region
       • Lined with mucosa - pseudostratified ciliated columnar epithelium
       • Nasolacrimal Ducts: drain lacrimal secretions from the surface of each eye into the resp region
   • Function
     • Condition air
       • Conditioning Process
         • 1. Air warmed to body temp
           • The vessels dilate in response to cold air, resuling in increased blood flow that helps to more effective warm the inhaled air.
         • 2. Air is cleansed
           • in haled microbes, dust, and other foreign material become trapped in the mucus covering the inner lining of the resp tract
         • 3. Cilia "sweep" the mucus and its trapped contents towards the pharynx to be swallowed
         • 4. Air is humidified
   • Paranasal Sinuses (Superior to Inferior)
     • Frontal
     • Ethmoidal
     • Maxillary
     • Posteriorly: Spenoidal