Lecture on Respiratory System Structures

Overview

• The lecture covers the structures of the respiratory system using a half-head model.
• Focuses on the nasal cavity, pharynx, and larynx.

Nasal Cavity

• Vestibule & External Nares:
  • Vestibule: Initial area in the nasal cavity.
  • External Nares: Outer openings where air enters.
• Tissue Composition:
  • Pseudostratified ciliated columnar epithelial tissue with cilia.
  • Functions: Humidify, warm, moisten, and filter incoming air.
  • Vibrissae (Nose hairs): Pick up particles.
• Nasal Conchae and Meatuses:
  • Superior, Middle, and Inferior Nasal Conchae.
  • Superior, Middle, and Inferior Meatuses respectively.
  • Function: Create turbulence to increase air contact with mucosal surfaces.
• Internal Nares:
  • Posterior apertures leading into the pharynx.

Pharynx

• Nasopharynx:
  • Lined with pseudostratified ciliated columnar epithelium.
  • Primarily for air passage.
• Oropharynx and Laryngopharynx:
  • Lined with stratified squamous epithelial tissue.
  • Handle air, food, and liquid contact.
• Tonsils and Tubes:
  • Pharyngeal tonsils, Tubal tonsils.
  • Eustachian tube: Connects to middle ear for pressure equalization.

Larynx

• Structures & Composition:
  • Epiglottis: Elastic cartilage, prevents food from entering the trachea during swallowing.
  • Vocal Cords:
    • False Vocal Cords: Above true vocal cords.
    • True Vocal Cords: Vibrate for sound production (phonation).
  • Glottis: Space between true vocal cords.
  • Cricothyroid ligament: Links cricoid and thyroid cartilages.
• Cartilages:
  • Thyroid Cartilage: Forms Adam's apple, more prominent in males due to testosterone.
  • Cricoid Cartilage: Complete ring, provides structure.
  • Arytenoid Cartilage: Controls vocal cord tension.

Additional Structures

• Palates:
  • Hard Palate: Bone structure separating nasal and oral cavities.
  • Soft Palate & Uvula: Muscle and connective tissue; elevates to prevent food from entering nasal cavity.
• Sinuses:
  • Frontal and Sphenoid Sinuses: Air-filled spaces within bones.

Conclusion

• The lecture provided a detailed examination of the respiratory system structures on a model.
• Emphasized the functions and interconnectivity of these structures in aiding respiration and phonation.