3- Throat (Anatomy and physiology) Flashcards
the oral cavity
- Nasal cavity separate to oral cavity= the hard and soft palate
- Tip of soft palate= uvula
- The tongue and 32 Teeth
- Area between lips and teeth= vestibule
- Palatoglossal and palatopharyngeal arches (Mc Donald’s signs)
-> Where tonsils sit
how may teeth do we have
32
how may teeth do we have
32
salivary glands
2x3
- Parotid
- Submandibular
- Sublingual
salivary glands
2x3
- Parotid
- Submandibular
- Sublingual
parotid gland
Saliva:It produces serous saliva – a watery solution rich in enzymes – which is then secreted into the oral cavity, where it lubricates and aids in the breakdown of food.
Contribution: second largest amount
Location
- Lies anterior to the SCM and ear
- Behind the masseter and zygomatic arch
- Duct opens up in the upper region of the oral cavity- Stenson’s duct (near upper 2nd molar)
submandibular gland
Type of saliva: mixed serous and mucous salivary secretions
- important for the lubrication of food during mastication to enable effective swallowing and aid digestion.
Contribution Most of saliva (60%)
Location
- Sits under the mandibular in the submandibular triangle
- Saliva exits the Wharton’s ducts
Think salivary calculi
Sublingual gland
Type of saliva: predominatley mucous
- These secretions are important in lubricating food, keeping the oral mucosa moist and initial digestion.
Contribution: Least at 3-5% of overall salivary volume
Location
- under the tongue
the tongue and motor supply
Intrinisc muscles (not atatched to other muscles exzcept outher intrinsic muscles.
- 4 pairs
- longitudinal
- transverse
- vertical
- inneration: hypoglossal
Extrinsic muscles- arise from other structures and insert into tongue
- genioglossus
- hyoglossus
- styloglossus -> hypoglossal nerve
- palatoglossu -> vagus nerve
the tongue and sensory supply
divided into anterior 2/3 and posteiror 1/3
Anterior 2/3
- sensation- trigeminal (V3)
- taste - facial
Posterior 1/4
- Sensation and taste - glossopharangeal
throat also known as
pharynx
throat also known as
pharynx
pharynx subdived into
- Nasopharynx
o Behind nasal cavity - Oropharynx
o Behind oral cavity - Laryngopharynx
o Behind larynx
The nasopharynx- upper pharynx
- Pink part in the photo
- Behind the nasal cavity
- Borders
o Base of skull- upper border
o C1,C2- posterior border - Nasal cavity- anterior border
- Contains
o Pharyngeal tonsil e.g. adenoids
The oropharynx- middle pharynx
- Yellow part on photo
- Starts where the nasopharynx end
- Borders
o Soft palate to epiglottis
o Anterior- oral cavity
o Posterior (C2,C3) - Contains
o Palatine tonsils
palatine tonsils
Laryngopharynx – lower pharynx
- Blue part on photos
- Borders
o Oropharynx to oesophagus
o Epiglottis to cricoid cartilage
o Anterior- larynx
o Posterior (C4, C5, C6) - Contains
o Piriform fossa
Piriform fossa
Epiglottis (flap on right photo) acts as a director of flow of fluid and water into the piriform fossa into the oesophagus instead of the trachea
General overview of nerve innervation of pharynx
satges of swallowing
1) Oral phase
2) Pharyngeal phase
3) Oesophageal phase
oral stage of swallowing
- Voluntary
- Tongue touching hard-palate to bring bolus to the pharynx
pharyngeal phase
- Involuntary
- Tongue touching hard palate
- Soft palate elevation
- Dangerous stage- shared airway space
o Need to protect airway
-> By shortening longitudinal muscles- elevate larynx and pharynx -> widening it
-> Closure of epiglottis (sealing the airway)
oesophageal phase
- Relaxes upper oesophageal sphincter
- Rapid peristalsis
- Lower oesophageal sphincter relaxes and bolus goes into stomach
