The nasal and paranasal cavities

Question 1

What are the 3 distinct compartments?

Answer 1

1. External nose
2. nasal cavities
3. paranasal cavities

Question 2

why does your nose run when you cry?

Answer 2

As the nasolacrimal duct opens into the vestibule . Fluid from the tears, is draining through the duct.

Question 3

What is the external nose?

Answer 3

• An external plate located on the philtrum
• the paired nasal cavities are separated by the nasal septum
• is flexible and cartilaginous
• unmodified skin
• extends back into the vestibule and in these areas is covered by mucosa

Question 4

What are the nasal cavities?

Answer 4

• twinned pair of cavities
• contains a turbinate bones covered by mucosa conchae
• certain bones bordering nasal cavity are thickened by air spaces. They aren’t part of the nasal cavity, but communicate with the cavity. These spaces are called paranasl sinuses.

Question 5

What features of the neighbouring anatomy reduced tight size of the nasal cavity?

Answer 5

• Paranasal sinuses in neighbouring bones
• embedded portion of upper cheek teeth occupy a surpring amount of spacde
• mucosal covering of the turbinate bones

Question 6

What are conchae?

what are meatus(es) ?

what are the sizing of the conchae like?

Answer 6

• Conchae are folding of the nasal inner wall. They compartmentalise the nasal cavity*
• meatus(Es) are the compartments for the nasal cavity*
• rotstarlly, the dorsal and ventral conchae are very large, where as the middle conchae is relatively small*

Question 7

Where does the horses septum rum?

Answer 7

the entire length of the hard palette

Question 8

1. What is the point in the compartmentalising the nasal cavity?
2. what do the different compartments do?
3. whats the nasal cavity like of an animal which has an accuse sense of smell?

Answer 8

1. Creates flow of the air and creates a turbine for the flow of air. Also so that the air can be sniffed and used for different purposes
2. Dorsal most meatus is for the sense of smell. The middle meatus is for access to the perinatal sinuses. The air in the ventral sinus is for is encounte to the lungs
3. the better the sense of smell, the less the cavity is filled, and has extensive conchae

Question 9

What are each conchae sepearted by?

what is the ethmoidal turbinates?

Answer 9

• by narrow clefts*
• towards the olfactory bulb. Are finer with a LSA covered in mucosa still. Covered in nerve endings driectly from bulb., so gives the sense of smell*

Question 10

PARANASAL SINUSES:

1. what are they
2. how are they connected to the nasal cavity
3. what do all domestic species have
4. what is their no connection between

Answer 10

1. are excavations of the neighbouring bones with air
2. by small openings
3. frontal and maxillary
4. no contra-lateral sinus connection

Question 11

What is the frontal sinus?

what is the maxillary sinus?

Answer 11

• Opens into the nasal cavity in ethmoid meatus. (Via caudal maxillary sinuous in the horse though )*
• opens into nasal cavity within caudal/lateral part of the upper jaw. Is associated with the hard palette, sphenoid bones, orbit and ventral conchae.*

Question 12

What is the horses frontal and maxillary sinus like?

what happens to the sinuses as the horse ages and grows?

Answer 12

• frontal sinus=huge with a caudal and rostral part.*
• maxillary sinus= has 2 halves. Is connected to the middle nasal meatus, ton allow for drainage. As the horse ages, the sinus gets larger as the skull grows, and moves further caudally.*
• The sinuses get more extensive, and hollow out the bones more. This makes them lighter. Their position relative to the teeth changes a bit.*