The Larynx

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1. Cartilages (skeletal framework):
   Unpaired cartilages:
   Thyroid cartilage (largest, forms the "Adam’s apple").
   Cricoid cartilage (complete ring below the thyroid cartilage).
   Epiglottis (leaf-shaped flap that covers the airway during swallowing).

Paired cartilages:
Arytenoid cartilages (pyramidal, control vocal cord movement).
Corniculate cartilages (tiny, sit on top of arytenoids).
Cuneiform cartilages (small, embedded in the aryepiglottic folds).

2. Membranes and ligaments (connective structures):
   Thyrohyoid membrane (links thyroid cartilage to hyoid bone).
   Cricothyroid ligament and membrane (between cricoid and thyroid cartilages; site for cricothyrotomy).
   Cricotracheal ligament (connects cricoid to trachea).
   Quadrangular membrane and conus elasticus (form part of the vocal and vestibular folds).

3. Folds (mucosal structures):
   Vocal folds (true vocal cords) – produce sound.
   Vestibular folds (false vocal cords) – protective, do not normally produce sound.
   Aryepiglottic folds – form the laryngeal inlet.

4. Cavities:
   Laryngeal vestibule (from inlet to vestibular folds).
   Laryngeal ventricle (between vestibular and vocal folds).
   Infraglottic cavity (below vocal cords, continuous with trachea).

5. Muscles:
   Intrinsic muscles (control vocal cord movement, e.g., cricothyroid, posterior cricoarytenoid, lateral cricoarytenoid, thyroarytenoid, transverse/oblique arytenoids).
   Extrinsic muscles (move the larynx as a whole, e.g., suprahyoids and infrahyoids).

6. Nerve supply:
   Recurrent laryngeal nerve (branch of vagus) – motor to all intrinsic muscles except cricothyroid; sensory below vocal cords.
   External branch of superior laryngeal nerve – motor to cricothyroid.
   Internal branch of superior laryngeal nerve – sensory above vocal cords.