2.1 headgut, pharynx, larynx Flashcards
define prehension
the intake of food through the mouth
define mastication
the mechanical break down of food
allow mixing with saliva
define deglutition
the act of swallowing in several phases
what are the phases of deglutition and what differences do they have
initial phase is voluntary
the remaining phases are involuntary
what is the 4 musculature of prehension (4)
- Zygomaticus: Retracts the mouth’s angle.
- Levator labii superioris: Elevates the upper lip.
- Buccinator: Keeps food between molar teeth during mastication.
- Orbicularis oris: Closes lips, assists in gathering food .
function of zygomaticus
retracts the mouth’s angle
function of levator labii superioris
elevates the upper lip
function of buccinator
keep food between molar teeth during mastication
orbicularis oris
close lips, assisting in gathering food
where are the location of the prehension muscles
look at diagram
location of the oral cavity
extends from lips to the entrance into the pharynx
what’s the difference between hard palate and soft palate
- Hard palate has a bone with it
- Soft palate doesn’t have a bone with it
function of the hard palate
- separate the oral cavity from the nasal cavity
function of the nasopharynx
a passage from nasal cavity to the larynx and trachea
is the trachea dorsal or ventral to the oesophagus
ventral
function of oropharynx
passage for both food and air
function of the larynx
for sound production
function of the epiglottis
a flap of cartilage that covers the trachea during swallowing, preventing food from entering the airway
where is the guttural pouch present
in horses
function of the guttural pouch
- reduce in density of the head
- involve in formation of horses voice
- for thermal regulation
what structural difference is with brachycephalic dogs
very long soft palate
how does the structural difference in brachycephalic dogs affect them
the soft palate blocks the entrance of larynx and the trachea, causing snoring and breathing problems
what surgery helps with brachycephalic dogs
BOAS surgery
how does BOAS surgery work
Cut parts of the soft palate to unblock the entrance to the larynx and the trachea
what are the 2 muscles for swallowing (soft palate)
tensor veli palatini
levator veli palatini
function of the 2 muscles for swallowing
During swallowing, they assists in elevating the soft palate to seal off the nasopharynx from the oral cavity, preventing food from entering the nasal passages.
The elevation caused by tensor veli palatini and levator veli palatini results in the caudal free edge of the soft palate pressing on the pharyngeal wall, sealing off the nasopharynx
The action of the tensor veli palatin
the 3 divisions of the pharynx
nasopharynx
oropharynx
laryngopharynx
what is monostomatic and polystomatic glands
Monostomatic glands - delivers saliva to a distant site through a single duct
Polystomatic glands - produce saliva locally through multiple openings adjacent to the saliva-producing glands
what are the 4 minor salivary glands
- lingual
- labial
- buccal
- palatine
what are the 4 major salivary glands (1 of them might not count as major)
- parotid
- sublingual
- mandibular
- zygomatic
salivary gland innervation
Sympathetic:
vasoconstriction and the flow of saliva decreased
Parasympathetic (most important):
- Facial (CN Vll)
- Glossopharyngeal (CN lX)
why do we release less saliva in sympathetic nervous system
When we are nervous, our mouth gets dry, because less saliva flow = less digestion of food as not needed
where is the hyoid apparatus located
in the larynx
5 bone type of the hyoid apparatus
basialhyoid
epihyoid
stylohyoid
keratohyoid
thyrohyoid
which one of the bones are paired and which are unpaired
basilhyoid - unpaired
the rest of them are paired
function of the hyoid apparatus
hold the larynx in place
location of the bones of the hyoid apparatus
look at diagram
what are the unpaired cartilage associated with the hyoid apparatus
Epiglottis, Thyroid, and Cricoid.
what are the paired cartilage associated with the hyoid apparatus
Arytenoid
4 laryngeal muscle
- ventricularis
- cricoarytenoideus
- thyroarytenoideus
- vocalis
function of ventricularis
vocal fold adduction (bringing the vocal cords together) and glottis constriction (narrowing the spaces between vocal cords)
function of cricoarytenoideus dorsalis
abducts the arytenoid cartilage to open the glottis
function of thyrotenoideus
give rise to ventricularis and vocalis muscles
function of vocalis
control vocal cord
function of tongue
- Grooming
- Lapping
- Prehension food in the oral cavity
- Delugtition reflex
- vocalisation
what is lyssa
rod like structure in the middle of a dogs tongue
how do dogs consume water
Dog tongue swings backward, acting like a cup holding water, pulling it into the oral cavity
tongue intrinsic muscles
dorsal and ventral longitudinal muscle
tongue extrinsic muscles
- styloglossus
- genioglossus
- hyoglossus
- geniohyoideus
function of styloglossus
- it retracts and elevates the tongue
function of genioglossus
- it protrudes and depressed the tongue
function of hyoglossus
it retracts and depresses the tongue
function of geniohyoideus
it lies below the tongue (not within it) and draws the hyoid and therefore the tongue forwards
tongue innervation
Movement: hypoglossal nerve (CN Xll)
Sensory (temperature and touch)
types of papilla (5)
- conical
- foliate
- vallate
- fungiform
- filiform
details about conical
Types of papillae:
- Conical - mechanical
a. Absent in horses
b. Present in the caudal 1/3 of the tongue
c. No taste buds
details about foliate
- Foliate (gustatory)
a. Absent in ruminant
b. Present in the caudal 1/3 of the tongue
c. Taste buds present
d. 8-12 papillae in parallel folds, one either side of the tongue midline
details about vallate
- Vallate (gustatory)
Taste buds and lymphatics present
details about fungiform
- Fungiform (gustatory)
a. Red dots
b. Consists of blood vessels
c. They are involved in heat loss by panting in dogs
d. Contain taste buds
details about filiform
- Filiform (mechanical)
a. No taste buds
Very prominent in cats
