3. Oral Cavity, Tongue, and Salivary Glands I

Question 1

Main functions of oral cavity:

Answer 1

-prehension=getting food
-mastication=chewing
-insalivation of food
-aggression and defense
-breathing
-vocalization

Question 2

Oral cavity includes:

Answer 2

-walls of oral cavity
-accessory structures that project into it (teeth, tongue)
-structures that drain into it (salivary glands)

Question 3

Oral cavity location:

Answer 3

-entered between lips and continues into pharynx

Question 4

Lips are made of:

Answer 4

-skin
-intermediate layer of muscle
-tendon
-glands
-oral mucosa

Question 5

Salivary glands: lips

Answer 5

-small ones are scattered among muscles below mucosa

Question 6

Mimetic muscles:

Answer 6

-muscles that are not to do with chewing
-encircle mouth
-raise, depress or retract lips
*all supplied by facial nerve (cranial nerve 7)

Question 7

What determine form of lips?

Answer 7

-diet and feeding habits
-wide gape vs. smaller opening

Question 8

Wide gape lips:

Answer 8

-needed to use teeth in seizing prey or in fighting

Question 9

Smaller opening lips:

Answer 9

-suffices in most herbivores and rodents

Question 10

New born animals:

Answer 10

-lips form seal around the teat for suckling

Question 11

Lips in dogs:

Answer 11

-extensive, but thin
-can be drawn back from teeth to show aggression
-not that motile, serrated margin

Question 12

Lower lip of dogs:

Answer 12

-loose, but fastened to lower jaw at level of canine

Question 13

Lips in horses:

Answer 13

-sensitive and mobile for food prehension
-some have hair on upper lip (vibrissae or whiskers)

Question 14

Lips in cattle:

Answer 14

-thick and insensitive (tongue is used to collect food)
-area above lip is a nasolabial plate

Question 15

Nasolabial plate: cattle

Answer 15

-area above upper lip
-modified hairless and moist skin
-can be used for nose-printing for ID
-conical papillae

Question 16

Lips in sheep and goat:

Answer 16

-used for prehension of food=motile
-hairless skin is much smaller=philtrum
-conical papillae

Question 17

Conical papillae:

Answer 17

-protect mucosa from roughage in ruminants

Question 18

Oral cavity divided by:

Answer 18

-teeth and margins of jaws into outer vestibule
-bounded by lips/cheeks externally
-central oral cavity proper

Question 19

Cheeks (buccae):

Answer 19

-are structurally similar to lips
-in herbivores: have protective buccal papillae

Question 20

Buccinator muscle:

Answer 20

-main support of oral cavity to return food into oral cavity proper

Question 21

Salivary glands in the oral cavity:

Answer 21

-buccal salivary glands

Question 22

Buccal folds:

Answer 22

-allow occasional maximum opening of mouth while avoiding injury by teeth

Question 23

Caudal limit of oral cavity:

Answer 23

-marked by Palato-glossal arch (palate-tongue)
>mucosal folds from soft palate to each side of tongue root
>seen best when tongue is pulled to one side

Question 24

Beyond oral cavity:

Answer 24

-oropharynx starts
>has palatine tonsils on it’s caudolateral surfaces

Question 25

Frenulum:

Answer 25

-joins the tongue to the floor of the oral cavity >sublingual caruncle on each side >drainage to some salivary glands

Question 26

Palate:

Answer 26

-roof of oral cavity proper

Question 27

Hard palate:

Answer 27

-flat in most species (vaulted in humans) -dental pad -rugae -palatine raphe -buccal papillae

Question 28

Herbivores hard palate:

Answer 28

-covered by heavily keratinized transverse ridges (rugae), on either side or palatine raphe

Question 29

Dental pad:

Answer 29

-ruminants -tough but yielding cushion in lieu of upper incisive teeth, as counterpart to lower teeth

Question 30

incisive papilla:

Answer 30

-flanked by incisive canals >usually continue to the nasal cavity

Question 31

Tongue is involved in:

Answer 31

-prehension -lapping -grooming -mastication -speech -heat loss

Question 32

Tongue:

Answer 32

-highly muscular >capable of vigorous and precise movements

Question 33

Parts of the tongue:

Answer 33

-apex -base -root

Question 34

Apex of tongue:

Answer 34

-free moving tip (rostral)

Question 35

Body of tongue:

Answer 35

-attached to mandibular symphysis and supporting muscles (mylohyoideus)

Question 36

Root of tongue:

Answer 36

-attached to the hypoid bone (caudal)

Question 37

Intrinsic and extrinsic muscles of the tongue:

Answer 37

*intermingle

Question 38

Intrinsic muscles of the tongue:

Answer 38

-not named -fibers go in different directions -have structural fat mixed with fibers

Question 39

3 extrinsic muscles of the tongue:

Answer 39

-enter tongue -names end in ‘glossus’ 1. Genioglossuss 2. Styloglossus 3. Hypoglossus

Question 40

Genioglossus:

Answer 40

-from symphysis go in median plane -some fibers thru frenulum to apex, body and root

Question 41

Genioglossus to apex:

Answer 41

-retract the tongue

Question 42

Genioglossus to body:

Answer 42

-depress tongue

Question 43

Genioglossus to root:

Answer 43

-protract the tongue

Question 44

Hypoglossus:

Answer 44

-from hyoid (thyrohyoid and basihyoid) to root of tongue >retract and depress -more lateral

Question 45

Styloglossus:

Answer 45

-fibers from stylohyoid to body of tongue >retract and elevate -most lateral

Question 46

Supportive muscles of the tongue:

Answer 46

-mylohyoideus -geniohyoideus

Question 47

Mylohyoideus:

Answer 47

-fibers go across inter-mandibular (like a hammock) >support and raise tongue -thin layer

Question 48

Geniohyoideus:

Answer 48

-from symphysis to basihyoid >bring hyoid and tongue forward -cord like