Anatomy Flashcards
what are 4 functions of the upper GI tract?
1) mastication (chewing)
2) taste
3) deglutition (swallowing)
4) Salivation
what muscle and feature of the mouth controls mastication?
= temporo-mandibular joint
- muscles of TMJ, face and tongue
- dentition (teeth)
what 4 things are involved in deglutition (swallowing)?
- tongue
- palate
- pharynx
- oesophagus
what 4 glands are involved in salivation?
- parotid gland
- submandibular gland
- sublingual gland
- minor glands
what 3 things are involved in taste?
- mastication
- salivation
- tongue
how is mastication (chewing) conducted?
what does mastication facilitate?
by movement of jaw which occurs at the TMJ and tongue, to breakdown good.
- facilities taste and digestion by mixing food with saliva
how many teeth do adults have?
and how many quadrants do the mouth have?
= 32 teeth
4 quadrants
- upper right
- upper left
- lower right
- lower left
what 3 points does the TMJ articulate?
1) mandibular fossa
2) head of condylar process
3) articular tubercle
what are all the muscles of mastication supplied by?
= mandibular division of tri-geminal nerve
CN V3
how many muscles are there at each TMJ?
4 muscles
- 3 close
- 1 opens
what are 4 muscles involved in mastication?
1) temporlais muscle
2) masseter muscle
3) lateral pterygoid
4) medial pterygoid
describe what the temporalis and masseter muscle are?
TEMPORALIS
- coronoid process of mandible to temporal fossa
MASSETER
- angle of mandible to zygomatic arch
describe what the lateral and medial pterygoid are?
LATERAL PTERYGOID
- condyle of mandible to pterygoid plates of sphenoid bone
MEDIAL PTERYGOID
- angle of mandible (Medial side) two pterygoid plates of sphenoid bone
what are the 2 cavities of TMJ and what do they each allow?
1) superior cavity
= translation
2) inferior cavity
= rotation
what are the 2 cavities in TMJ divided by?
= articular discs
what function do mandibular division of tai-geminal nerves (CNV3) have?
= sensory and motor fibres
describe the course of the mandibular division of tai-geminal nerve (CNV3)?
- from pons
- through foramen oval
- to muscles of mastication and sensory area
see diagram of oral cavity
see diagram of oral cavity
see diagram of surface anatomy of oral cavity
see diagram of surface anatomy of oral cavity.
what things should you be cautious of in the oral cavity?
- any dental work
- loose teeth or loose parts of teeth = choking hazard and an aspiration risk
= aspiration is the inhalation of liquid or solid matter into lungs - potential infection
match the following; Posterior 1/3rd Anterior 2/3rd with Vertical part Horizontal part
Posterior 1/3rd = vertical part
Anterior 2/3rd = horizontal part
where is the posterior 1/3rd and anterior 2/3rd found?
Posterior 1/3rd in oropharynx
Anterior 2/3rd in oral cavity
what are the functions of posterior 1/3rd and anterior 2/3rd of the tongue?
Posterior 1/3rd = taste & general sensation (CNIX)
Anterior 2/3rd = general sensory (CNV3)
what are the different points of the tongue?
TIP = filiform papillae
MID = fungiform papillae
BACK = vallate papillae
BACK EDGE = foliate papillae
what is the course of the facial nerves?
- from ponto-medullary junction
- travels through temporal bone via internal acoustic meatus then stylomastoid foramen
To supply;
- taste ant. 2/3rds tongue
- muscles of facial expression
- glands in floor of mouth
see slide on facial nerve course diagram.
see slide on facial nerve course diagram
describe whats on the superior half of oral cavity?
and what is the general sensation of superior half of oral cavity?
= gingival of oral cavity and palate
- CN V2
what particular area of the oropharynx is extremely sensitive to touch?
= posterior wall
describe whats on the inferior half of oral cavity?
and what is the general sensation of inferior half of oral cavity?
= gingival of oral cavity & floor of mouth
- CN V3
what is the gag reflex?
a protective reflex preventing foreign bodies from entering the pharynx or laryngeal
what is sensory part of the gag reflex carried by?
what is the motor part of the gag reflex carried by?
Sensory
= by nerve fibres within CN IX
Motor
= by nerve fibres within CN IX and CN X
part of the gag reflex involves response to touching posterior wall of oropharynx, why is this?
to constrict pharynx, as patient attempts to close it of as an entry point into node
if you spray a local anaesthetic into the mouth, what sensory action potential will it block?
- CN V2
- CN V3
- CN VII
- CN IX
what is the course of CN V2?
- from pons
- through foramen rotundum
- to sensory area (mid-face)
what is CN IX also known as?
= glossopharyngeal
- special sensory, motor, visceral afferent and parasympathetic
what is the course of CN IX?
- from medulla
- through jugular foreman
- to posterior wall of oropharynx (sensory), parotid gland (secretomotor), and post
1/3rd tongue (sensation and taste)
what are the 3 salivary glands?
1) parotid gland
2) sub-mandibular gland
3) sub-lingual gland
where are the salivary glands located?
Parotid
- parotid duct crosses face secretes into mouth by upper 2nd molar
Sub-Mandibular
- sub-mandibular duct enters floor of mouth secreting via lingual caruncle
Sub-lingual
- lays in floor of mouth secreting via several ducts superiorly
what can duct clotting/blockage cause?
- swelling due to back up of secretions
how is the tongue suspended in oral cavity?
by 4 Paris of skeletal muscle;
- PALATOGLOSSUS
- STYLOGLOSSUS
- GENIOGLOSSUS
- HYYPOGLOSSUS
what are the functions of the extrinsic muscles of the tongue?
- function to change the position of the tongue during mastication, swallowing and speech
where are the 4 pairs of skeletal intrinsic muscles of tongue located and what is their function?
- mainly dorsally/posteriorly
Function = to modify the shape of the tongue during function
what are all the tongue muscles innervated by?
CN XII (hypoglossal nerve)
EXCEPT PALATOGLOSSUS
describe the course of the hypoglossal nerves, CN XII?
- from medulla
- through hyypoglossal canal
- to intrinsic and extrinsic muscles of tongue (except palatoglossus)
how many circular (constrictor) muscles does the pharynx have?
and what layer do they form of the pharynx?
3x circular (constrictor) muscles
= the external layer
what are the circular constrictor muscles in the pharynx like?
= voluntary muscles
what do the external (circular) layers of the pharynx overlap with?
= each other and contract sequentially
what is the pharynx circular muscles innervated by?
CN X (vagus)
where is the CN X inserted in the pharynx?
= onto the midline raphe
how many longitudinal muscles are there in the pharynx?
= 3x longitudinal muscles
what are the longitudinal muscles in the pharynx like?
skeletal (voluntary) muscles
what layer do the longitudinal muscles make up of the pharynx?
= inner layer
what are the longitudinal muscles innervated by?
- CN X and IX (one muscle, stylopharyngess)
what do both the internal and external layers of the pharynx do?
elevate the pharynx and larynx
- attach to laryngeal
- contrat to shorten pharynx
- raise larynx to close over the laryngeal inlet
what is used to view inside the GI tract?
endoscopy
when you insert an endoscopy, what should you ask the patient to do?
swallow
what happens when you ask the patient to swallow?
1) tongue pushes bolus of food towards oropharynx
= voluntary
2) soft palate elevated, larynx elevated
= involuntary
3) circular layer of pharyngeal constrictor mussels contract
= involuntary
4) bolus of food enters oesophagus and travels inferiorly by peristalsis
= involunttary
what is the anatomy of swallowing?
1) Close the lips to prevent drooling (orbicularis oris & cranial nerve VII)
2) The tongue (cranial nerve XII) pushes the bolus posteriorly towards the
oropharynx
3) Sequentially contract the pharyngeal constrictor muscles (cranial nerve X) to
push the bolus inferiorly towards the oesophagus
4) At the same time the inner longitudinal layer of pharyngeal muscles (cranial
nerves IX & X) contracts to raise the larynx, shortening the pharynx and closing off the laryngeal inlet to help prevent aspiration
5) The bolus reaches the oesophagus
what are all the muscles of involved in swallowing?
skeletal muscles
is the initiation of swelling involuntary or voluntary?
voluntary
what are all the muscles of swelling supplied by?
cranial nerves