oral cavity and mastication SDL

Question 1

How do mammals chew and breathe at the same time?

Answer 1

By sealing off the buccal cavity and oropharynx from the common pharynx: seal is made by tongue against soft palate, and soft palate against epiglottis.

Question 2

What is the embryological origin of the gut epithelium

Answer 2

endoderm

Question 3

Where is the transition between the skeletal muscles of the oral cavity and the smooth muscle of the stomach?

Answer 3

Oesophagus. Cats, pigs, horses have extensive smooth muscle, other species mainly skeletal muscles until last part of oesophagus.

Question 4

which cranial nerves are responsible for olfaction

Answer 4

olfactory (I)

Question 5

which cranial nerves are responsible for skin sensation of the lips

Answer 5

trigeminal maxillary and mandibular

Question 6

which cranial nerves are responsible for lip movement

Answer 6

facial (VII)

Question 7

which cranial nerves are responsible for jaw opening

Answer 7

trigeminal and facial

Question 8

which cranial nerves are responsible for tongue movement

Answer 8

hypoglossal (XII)

Question 9

which cranial nerves are responsible for taste

Answer 9

Rostral 2/3 of tongue is VII, caudal 1/3 is IX, larynx is X.

Question 10

which cranial nerves are responsible for jaw closing

Answer 10

trigeminal mandibular branch

Question 11

what hindrances are there to intubating a chinchilla

Answer 11

pharyngeal ostium

Question 12

what is the diastema

Answer 12

dental gap between incisors and premolars

Question 13

embryological origin of ameloblasts and what they produce

Answer 13

oral ectoderm - produce enamel

Question 14

what is the embryological origin of odontoblats and what do they produce

Answer 14

neural crest cells - dentine

Question 15

what does heterodont mean

Answer 15

different types of teeth

Question 16

what happens to tooth pulp with age

Answer 16

It gets smaller as the odontoblasts migrate through the pulp laying down secondary dentine.

Question 17

What is the difference between primary and secondary dentine

Answer 17

Primary = laid down as tooth grows inside the bone (ie as a fetus or neonate).
Secondary = laid down in the erupted tooth.