Intro to Respiratory Flashcards
What are the primary functions of the respiratory system?
- Gas exchange
- Vocalization
- Olfaction
- Temperature control (cooling of blood through evaporation of water in the URT)
- Acid- base regulation (regulation of blood pH)
What is respiration necessary for regarding metabolism?
Oxidative metabolism. e.g. glucose metabolism:
C6H12O6+6O2–> 6CO2+6H2O+ ATP
What is the nasopharynx associated with?
Auditory tubes
What does dolichocephalic mean and what species is an example?
Long snout- greyhound
What does mesaticephalic mean and what species is an example?
Medium length snout- beagle
Who has a nasal plate?
Carnivores and small ruminants (sheep and goats)
Who has a nasolabial plate?
Ox (underlying glands to keep nasal plate moist)
Who has a rostral plate?
Pig- contains rostral bone
How do dogs keep their noses moist?
overflow from nasal cavity
What is the mucocutaneous junction? Where it is?
Within vestibule- site of opening of lateral nasal gland ducts (and nasolacrimal duct in horse)
What separates the nasal from the oral cavity?
Hard palate
What is the caudal limit of the nasal cavity?
Ethmoid bone
What divides up the nasal cavity (not referring to the nasal septum)?
Conchae (turbinate bones)- divided into small passages.
Delicate scrolls of bone, covered in mucosa, projecting into nasal cavity from dorsal and lateral walls.
How does the nasal cavity communicate with the nasopharynx? What is its purpose?
Choana. Air passes from nasal cavity into nasopharynx.
What is the rostral part of the nasal septum called?
Septal cartilage
What moves the nasal cartilage?
Levator nasolabialis and caninus (facial nerve- CNVII)
What are the three conchae?
- Dorsal- single elongated scroll
- Ventral- rostral part of nasal cavity (double scroll in most species; horse- single scroll; dog- complex, filling ventral part of nasal cavity)
- Ethmoidal (=ethmoturbinates)- numerous fine bony scrolls attached to ethmoid bone and lateral and dorsal walls (support olfactory mucosa)
What do the nasal chonchae do?
Increase surface area for heat exchange, filtration, and humidification of air by nasal mucosa and for olfaction (ethmoidal concha)
Divide cavity into dorsal, middle, ventral, and common nasal meatuses
What is the lateral nasal gland? Who has it?
Carnivores. Large serous gland between mucosa and maxillary bone in lateral wall. Duct opens in lateral wall of nasal vestibule. Secretions important in wetting external nose.
What is the purpose of the nasolacrimal duct?
Duct which drains tears from eye to rostral part of nasal cavity. Proximal opening at medial canthus of eye. Distal opening in nasal vestibule. (at mucocutaneous junction in horse & just ventral to alar fold in dog)
What are the paranasal sinuses?
Diverticula (outpocketings) of nasal cavity into skull bones, increase in size with age, lined with normal secretory nasal epithelium, frontal and maxillary present in all species.
Functions: lighten skull and bony development for muscle attachment, probably thermal and mechanical protection of soft tissues of head, resonance of voice
Frontal sinuses
drain into ethmoid region (except in horse)
Extend into cornual process (base of horn) in ruminants
Maxillary sinuses
Communicate with nasal cavity through narrow nasomaxillary opening except in dog and cat- wide opening maxillary recess
house roots of upper cheek teeth
In some species further diverticula into adjacent bones (e.g. palatine sinus)
Where does the frontal sinus drain in a horse?
Caudal maxillary sinus
