Nasal Sensation Screencast

Question 1

What are the three distinct parts of the nasal cavity?

Answer 1

Nasal vestibule, respiratory epithelium, olfactory epithelium

Question 2

What cells line the nasal vestibule?

Answer 2

Stratified squamous epithelium (keratinised to non-keratinised)

Question 3

What does the nasal vestibule represent?

Answer 3

The initial transition from the skin of the face to specialised mucosa of the nasal cavity

Question 4

Where does the respiratory epithelium cover in the nasal cavity?

Answer 4

Middle and inferior cochlea and their associated meatuses

Question 5

Where is the olfactory epithelium located in the nasal cavity?

Answer 5

Located superiorly = covers superior cochlea and spheno-ethmoidal recess

Question 6

What is the function of the nasal conchae in olfaction?

Answer 6

Create turbulence which holds air in the nasal cavity for longer to allow air to reach olfactory sensors on the roof

Question 7

What do olfactory receptors form?

Answer 7

Olfactory epithelium

Question 8

How can olfactory nerve receptor cells be described as bipolar?

Answer 8

Have their cell bodies within the epithelium, have dendrites which pick up odorants, and axons which convey these through the cribriform plate

Question 9

Which bone is the cribriform plate associated with?

Answer 9

The ethmoid bone

Question 10

Where is the olfactory area split between?

Answer 10

On the lateral wall of the nasal cavity and the nasal septum

Question 11

What nerve provides special sensory olfaction input and output?

Answer 11

Cranial nerve I (olfactory nerve)

Question 12

What is the olfactory pathway?

Answer 12

Receptor cells in olfactory epithelium
Pass up through cribriform plate
Synapse with olfactory bulb (ganglia)
Neurons pass along the olfactory tract
Go to temporal lobe and olfactory areas

Question 13

What provides general somatic sensory innervation to the anterosuperior aspect of the nasal cavity?

Answer 13

Ophthalmic division of the trigeminal nerve (CN V1)

Question 14

What provides general somatic sensory innervation to the postero-inferior aspect of the nasal cavity?

Answer 14

Maxillary division of the trigeminal nerve (CN V2)

Question 15

What nerve represents the ophthalmic division of the trigeminal nerve in supplying the nasal cavity?

Answer 15

Anterior ethmoid nerve (CN V1) = passes through anterior ethmoidal foramina closely related to the cribriform plate

Question 16

What provides general somatic sensation to the tip of the nose and the external bridge of the nose?

Answer 16

CN V1 = anterior ethmoid nerve

Question 17

What nerve represents the maxillary division of the trigeminal nerve in supplying the nasal cavity?

Answer 17

Nasopalatine nerve (CN V2) = passes through sphenopalatine foramen and courses inferiorly

Question 18

What features of the nasal cavity are covered by the nasopalatine nerve (CN V2)?

Answer 18

Middle and inferior conchae, and their associated meatuses

Question 19

Where does the nasopalatine nerve (CN V2) course on the septum?

Answer 19

Courses diagonally towards the incisive foramen and descends through this foramen

Question 20

What supplies the hard palate with general somatic sensation?

Answer 20

CN V2 = nasopalatine nerve

Question 21

Where does the nasopalatine nerve (CN V2) send axons towards once it passes through the incisive canal?

Answer 21

Sends axons towards the hard palate

Question 22

What is the ophthalmic division of the trigeminal nerve (CN V1) closely related to?

Answer 22

The orbits of the eyes = send axons through the orbit

Question 23

Where do axons from the ophthalmic division of the trigeminal nerve (CN V1) go once they have left the orbit?

Answer 23

Sent through the superior orbital fissure before having its cell bodies in the trigeminal ganglion

Question 24

Where is the trigeminal ganglion located?

Answer 24

On the lateral aspect of the cavernous sinuses in the middle cranial fossa

Question 25

Where does the trigeminal ganglion send its axons to?

Answer 25

Into the posterior cranial fossa and into the pons

Question 26

Where does the maxillary division of the trigeminal nerve (CN V2) send its axons to?

Answer 26

Sends axons through the foramen rotundum and into the trigeminal ganglion