Throat Anatomy & Physiology

Question 1

What are the different areas of the throat?

Answer 1

Question 2

What are the 2 parts of the oral cavity?

Answer 2

• Oral vestibule (between lips and teeth)
• Oral cavity proper

Question 3

What are the boundaries of the oral cavity?

Answer 3

• Lips to palatoglossal arch (anterior pillar)
• Palate to floor of mouth/tongue
• Buccal mucosa

Question 4

What is A?

Answer 4

Upper lip

Question 5

What is B?

Answer 5

Superior labial frenulum

Question 6

What is C?

Answer 6

Glossopalatine arch

Question 7

What is D?

Answer 7

Pharyngopalatine arch

Question 8

What is E?

Answer 8

Palatine tonsil

Question 9

What is F?

Answer 9

Salivary duct orifice - sublingual

Question 10

What is G?

Answer 10

Salivary duct orifice - submandibular

Question 11

What is H?

Answer 11

Inferior labial frenulum

Question 12

What is I?

Answer 12

Lower lip

Question 13

What is J?

Answer 13

Hard palate and tranverse palatine folds

Question 14

What is K?

Answer 14

Soft palate

Question 15

What is L?

Answer 15

Uvula

Question 16

What is M?

Answer 16

Fauces

Question 17

What is N?

Answer 17

Tongue

Question 18

What is O?

Answer 18

Lingual frenulum

Question 19

What is P?

Answer 19

Teeth

Question 20

What is Q?

Answer 20

Gingivae

Question 21

What are functions of the oral cavity?

Answer 21

• Taste
• Mastication
  
  • Teeth, tongue
• Speech
  
  • Tongue, cheek, lips
• Digestion
  
  • Salivary enzymes
• Swallowing
  
  • Tongue, hard and soft palate

Question 22

What are the 2 parts of the tongue?

Answer 22

• Anterior 2/3rds
  
  • From 1^st branchial arch
  • Sensation by lingual nerve (CN V3)
  • Taste by chorda tympani (CN VII)
• Posterior 1/3^rd
  
  • From 3^rd branchial arch
  • Supplied by CN IX

Question 23

Innervation of the tongue?

Answer 23

• Anterior 2/3rds
  
  • From 1^st branchial arch
  • Sensation by lingual nerve (CN V3)
  • Taste by chorda tympani (CN VII)
• Posterior 1/3^rd
  
  • From 3^rd branchial arch
  • Supplied by CN IX

Question 24

What are the 2 categories of tongue muscles and what is their function?

Answer 24

• Intrinsic muscles (after shape)
• Extrinsic muscles (after position)

Question 25

What are functions of the tongue?

Answer 25

* Taste * Mastication * Swallowing * Speech

Question 26

What is mastication?

Answer 26

Mastication = chewing

Question 27

What are the 4 muscles of mastication?

Answer 27

* Lateral pterygoid * Medial pterygoid * Temporalis * Masseter

Question 28

What is the nerve supply for mastication?

Answer 28

* CN V₃

Question 29

What are the boundaries of the oropharynx?

Answer 29

* Lower border of soft palate to upper margin of epiglottis * Palatoglossal arch to posterior pharyngeal wall * Lateral is faucial pillars and palatine tonsils

Question 30

What is the structure of the epithelium of the oropharynx?

Answer 30

* Stratified, non-keratinised squamous

Question 31

What is the nerve supply of the oropharynx?

Answer 31

* Pharyngeal plexus (CN IX and X)

Question 32

Where does the hypopharynx receive blood supply from?

Answer 32

Blood supply is the superior thyroid artery, lingual artery and the ascending pharyngeal artery

Question 33

What are the boundaries of the hypopharynx?

Answer 33

* Superior margin of epiglottis to lower border of cricoid cartilage * Continuous with oesophagus * Anterior wall back of pharynx

Question 34

What are the 3 subunits of the hypopharynx?

Answer 34

* Pyiform sinus * Post-cricoid area * Posterior pharyngeal wall

Question 35

What is the nerve supply of the hypopharynx?

Answer 35

* Pharyngeal plexus (CN IX and X)

Question 36

What are the 3 phases of swallowing?

Answer 36

1. **Oral phase (voluntary)** * Tongue propels food (bolus) into pharynx * Triggering swallowing reflex (afferent is CN V, IX and X, swallowing centre in the medulla, efferent by CN VII, X and XII) 1. **Pharyngeal** * Soft palate pulled upwards * Epiglottis covers the larynx, vocal cord approximate, larynx moves upward * Upper oesophageal sphincter (UOS) relaxes * Respiration is reflex inhibited 1. **Oesophageal** * Once bolus passed UOS, the sphincter constricts * Bolus propelled downwards by peristaltic motion, reflex via myenteric plexus

Question 37

What happens in the following phases of swallowing: 1) Oral 2) Pharynx 3) Oesophageal

Answer 37

1. Oral phase (voluntary) * Tongue propels food (bolus) into pharynx * Triggering swallowing reflex (afferent is CN V, IX and X, swallowing centre in the medulla, efferent by CN VII, X and XII) 1. Pharyngeal * Soft palate pulled upwards * Epiglottis covers the larynx, vocal cord approximate, larynx moves upward * Upper oesophageal sphincter (UOS) relaxes * Respiration is reflex inhibited 1. Oesophageal * Once bolus passed UOS, the sphincter constricts * Bolus propelled downwards by peristaltic motion, reflex via myenteric plexus

Question 38

What are the functions of the larynx?

Answer 38

* Part of the respiratory tract * Voice * Swallowing

Question 39

What are the 3 parts of the larynx?

Answer 39

* Supraglottis * Extends from the superior tip of the epiglottis to the floor of the ventricular fold (junction of respiratory and squamous epithelium) * Glottis * Begins superior at the true vocal fold and extends inferiorly to a horizontal plane 5mm inferior to the vocal cord * Subglottic * Begins 5mm below the free edge of the true vocal cord and proceeds to the inferior border of the cricoid cartilage

Question 40

What are the segments of cartilage in the larynx?

Answer 40

7 segments of cartilages: * Cricoid cartilage * Thyroid cartilage * Epiglottis * Paired arytenoid cartilages (corniculate and cuneiform)

Question 41

What are the muscles of the larynx?

Answer 41

* Extrinsic * Infrahyoid, suprahyoid and thyrohyoid * Move the entire laryngeal complex * Intrinsic * Regulate movement of the vocal folds

Question 42

Innervation of the larynx?

Answer 42

Motor innervation: * CN X * All intrinsic muscles supplied by recurrent laryngeal nerve except for cricothyroid muscle (external laryngeal) Sensory innervation: * Supraglottic by internal laryngeal nerve * Glottic and subglottic by recurrent laryngeal nerve

Question 43

What are intrinsic larynx muscles supplied by for motor innervation?

Answer 43

* All intrinsic muscles supplied by recurrent laryngeal nerve except for cricothyroid muscle (external laryngeal)

Question 44

What is the sensory innervation of: - supraglottic larynx - glottic larynx - subglotic larynx

Answer 44

* Supraglottic by internal laryngeal nerve * Glottic and subglottic by recurrent laryngeal nerve

Question 45

What are the different steps of speech?

Answer 45

1. Respiration 1. Source of energy, from air flow 2. Inhalation and exhalation 2. Phonation 1. Flow of air through different voice cord position, tension, vibration and length 3. Resonation 1. Oral/nasal speech balance 2. Depend on nasopharynx, nasal cavity and oral cavity 4. Articulation 1. Production of speech, determined by action of lips, tongue and jaw 5. Prosody 1. Production of syllable stress and emphasis 2. Provide effective speech tone