Larynx and Alimentary Structures

Question 1

Fourth and Sixth Arches
Nerves?
Muscles?
Skeletal structures?
Ligaments?

Answer 1

Superior laryneal branch of vagus nerve (X) and recurrent laryngeal branch of vagus nerve (X)

Cricothyroid m, Levator veli palatini, constrictors of pharynx, intrinsic muscles of larynx, striated muscles of esophagus

Skeletal structures: thyroid cartilage, cricoid cartilage, arytenoid cartilage, cuneiform cartilage, corniculate

Question 2

Action of cricothyroid muscle

Answer 2

stretch and tense vocal ligament

Question 3

Action of posterior crico-arytenoid muscle action

Answer 3

abducts vocal folds (opens rima glottis)

Question 4

Lateral crico-arytenoid muscle action

Answer 4

Adducts vocal folds (closes rima glottis)

Question 5

Transverse and oblique arytenoids action

Answer 5

Adduct arytenoid cartilages (closes rima glottis)

Question 6

Thyro-arytenoid action

Answer 6

Relaxes vocal ligament

Question 7

Vocalis action

Answer 7

Relaxes posterior vocal ligament while maintaining tension of anterior part

Question 8

Vessels and Nerves of the larynx

Answer 8

Recurrent laryngeal n
External branch of superior laryngeal (aka external laryngeal n)
Internal branch of superior laryngeal n (aka internal laryngeal n)

Question 9

Function of recurrent laryngeal n

Answer 9

Motor to all laryngeal muscles EXCEPT cricothyroid

Question 10

External branch of superior Laryngeal n aka external Laryngeal n function

Answer 10

Motor to cricothyroid m.

Question 11

Internal branch of superior laryngeal n (aka internal larygneal n) function

Answer 11

sensory to glottis, laryngeal vestibule and vocal folds; cough reflex (only above the level of vocal folds bc after that there is no sensory so you choke)

Question 12

1. Pharyngeal constrictors function

2. Associated pharyngeal muscles function

Answer 12

1. constrics the walls of the pharynx to contract the food bolus down into the esophagus
2. Elevates pharynx, larynx, while speaking to facilitate swallowing (stylopharyngeus, palatopharyngeus, tensor veli palatini, levator veli palatini)

Question 13

Describe the stage of swallowing: bolus of food is compressed against the palate by the tongue and pushed into the oropharynx

Answer 13

Stage 1: Voluntary

Question 14

Describe the stage of swallowing: Soft palate elevates, sealing off the nasopharynx from the oropharynx and laryngopharynx. The larynx elevates, thereby widening and shortening the pharynx to recieve the bolus of food

Answer 14

Stage 2: Involuntary and rapid

Question 15

Describe the stage of swallowing: The three pharyngeal muscles contract sequentially which forces the food bolus inferiorly into the esophagus

Answer 15

Stage 3: involuntary

Question 16

Describe the stage of swallowing: Peristaltic contractions move the food bolus down the esophagus

Answer 16

Stage 4: Involuntary