Larynx

Question 1

Function of larynx

Answer 1

Phonation
Cough reflex
Protective sphincter preventing foreign bodies from entering airway
Allows air passage in and out of trachea

Question 2

Anatomical relations to larynx

Answer 2

Superiorly opens into the laryngopharynx which forms its anterior wall
Continues inferiorly with trachea
Covered laterally by lobes of the thyroid gland
Posterior to larynx is oesophafus
Epiglottis swings down to protect airway

Question 3

Intrinsic laryngeal muscles and nerve supply

Answer 3

Control
- the shape of the rima glottidis (opening between the vocal folds and the arytenoid cartilages)
- length and tension of the vocal folds
- opening or closing of the laryngeal inlet

All intrinsic muscles except the cricothyroid are innervated by the recurrent laryngeal nerve and cricothyroid is innervated by the external branch of the superior laryngeal nerve
Both are branches of the vagus nerve

Question 4

Cricothyroid muscle

Answer 4

Intrinsic laryngeal muscle

Action: Lengthen and tenses the vocal folds to give higher pitch

Innervation: external laryngeal nerve of