Week 11: Larynx and Pharynx

Question 1

Where is the larynx located?

Answer 1

From the epiglottis until the lower border of cricoid cartilage (C6)

Question 2

The 3 main parts of the laryngeal skeleton

Answer 2

• Hyoid bone
• Thyroid cartilage
• Cricoid cartilage

Question 3

Thyroid cartilage landmarks

Answer 3

On each side:

• Superior and inferior horns.
• Lamina
• Angle

Question 4

The development of the thyroid is dependent on sex hormones. True or false?

Answer 4

True

Question 5

The arytenoid cartilage sits ____________ on the cricoid cartilage. It has _______ processes. Name them.

Answer 5

posterolaterally

2 processes

Muscular process (away from centre line)
Vocal process (towards centre line)

Question 6

2 movements of arytenoid cartilages are

Answer 6

Swivel in their own axis and coming together

Question 7

Vocal ligament attaches to what?

Answer 7

Vocal process of arytenoid cartilage and the angle of the thyroid.

Question 8

What produces sound?

Answer 8

The vibration of the vocal ligaments pressing on each other with air moving through it.

Question 9

What are the folds of the membrane in the larynx?

Answer 9

• Aryepiglottic fold
• False vocal cord (vestibular fold)
• Vocal cord (on top of vocal ligament)

Question 10

Which muscle is the only muscle that contributes to abduction of the vocal ligaments?

Answer 10

Posterior cricoarytenoid m.

Question 11

Which muscles contribute to adduction of the vocal ligaments?

Answer 11

• Lateral cricoarytenoid m.

- Oblique and transverse arytenoid m.

Question 12

Which muscles contribute to lower pitch sounds (lax vocal cords)?

Answer 12

• Vocalis m.

- Thyroarytenoid m.

Question 13

Which muscles contribute to higher pitch sounds (tight vocal cords)?

Answer 13

Cricothyroid m.

Question 14

Branches of the vagus n. that go to innervate the larynx.

Answer 14

• Superior laryngeal n. : innervates the mucosa.
• External laryngeal n. (only innervates the cricothyroid m. )
• Recurrent laryngeal n. (mucosa + all intrinsic muscles except cricothyroid m.)

Question 15

Vascular supply of larynx

Answer 15

Superior and inferior thyroid vessels.

Question 16

What are the 3 areas of the pharynx?

Answer 16

Naso, oro and laryngo.

Question 17

External sling muscles are

Answer 17

The constrictors. Superior, middle and inferior.

Question 18

Cricopharyngeus m.

Answer 18

Small constrictor below the inferior constrictor, most texts consider it part of the inferior constrictor.

Question 19

Internal layer of muscles (pharynx)

Answer 19

• Salpingopharyngeus
• Palatopharyngeus
• Stylopharyngeus

Question 20

Nasopharynx

Answer 20

Floor: soft palate
Walls: superior constrictor
Features: 
- opening of auditory tube
- pharyngeal tonsils (adenoids)
- salpingopharyngeus m.

Question 21

Oropharynx

Answer 21

Roof: soft palate
Floor: posterior part of the tongue
Walls: superior and medial constrictor m.
Features:
- 2 arches (palatopharyngeal and palatoglossal)
- palatine tonsils
- vallecula (space between tongue and epiglottis)

Question 22

Laryngopharynx

Answer 22

Located between epiglottis and oesophagus

Features:

• epiglottis (closing incomplete, cartilage)
• piriform recess (pathway for liquids)
• laryngeal inlet (larynx opening)

Question 23

Main and supporting SENSORY nerves of the pharynx

Answer 23

Main: Glossopharyngeal n.

Support:

• vagus n. (internal laryngeal branch) inferiorly
• trigeminal n. (maxillary branch) superiorly

Question 24

Main and supporting MOTOR nerves of the pharynx

Answer 24

Main: Vagus n.
Support: glossopharyngeal n. (innervating stylopharyngeus m.)

Question 25

Muscles that elevate the soft palate, and why would they do that?

Answer 25

• Tensor vali palitini
• Levator vali palitini

They elevate the soft palate during swallowing and coughing to prevent food or particles entering the nasal cavity.

Question 26

Muscles that depress the soft palate, and why would they do that?

Answer 26

• Palatoglossal m.
• Palatopharyngeus m.

They depress the soft palate during chewing to block the oral cavity, allowing free passage of air during breathing.