Introduction to the Respiratory System Flashcards
what is ventilation?
it is the process of breathing - movement of gases in and out of the lungs
what is respiration?
it includes distribution of gases in the alveoli and diffusion of oxygen into and carbon dioxide out of the bloodstream
secondary functions of the resp system?
regulation of pH of the body fluids, temp control and phonation
upper resp system consists of?
external nares, nasal cavity, concha
sinuses, larynx
lower resp system consists of?
trachea, lungs, bronchi
bronchioles and alveoli
what are the external nares?
air enters the nasal cavity through the nares/nostrils
these openings vary in size and shape
philtrum?
groove in the lip and middle of the nose separating nostrils (dogs and small ruminants)
planum nasale/planum nasolabiale?
non-haired most rostral part of the nose
planum nasolabiale - in species with large muzzle
nasal cavity?
separated from one another by cartilaginous (rostrally) nasal septum, caudally nasal bone
what is the ventral part of nasal cavities formed by?
formed by hard and soft palates hence separated from the mouth
vestibule - and middle part filled with?
vestibule is the entrance to the nasal cavity and the middle part is filled with conchae
nasal cavity lined with?
with mucosal membrane
what does each side of the nasal cavity communicate with?
communicates with the nostril of the same side (rostrally) and with the pharynx (caudally) by way of choanae (caudal nares)
conchae and meatus?
project inwards from dorsal to lateral walls
scroll like bones (turbinates)
covered with highly vascular mucous membranes
what does the meatus do?
separates the cavity into passages
dorsal and ventral conchae occupy?
they occupy rostral parts and caudally ethmoidal conchae (part of ethmoid bone)
describe the mucosa of the concha?
it is well vascularised and increase air turbulence
hence, humidifies and filters the inhaled air
cooling the blood that supplies the brain
what does the mucous membrane cover?
the ethmoidal conchae
what is the ethmoidal conchae?
the olfactory epithelium which contains sensory endings of the olfactory nerve
what nasal meatuses does the upper resp system have?
dorsal, middle and ventral nasal meatuses
what does the middle nasal meatus communicate with?
with paranasal sinuses
what does the nasal ventral meatus do?
it is the main pathway for airflow leading to pharynx
what is the common nasal meatus?
it is the longitudinal space
which is the widest and best route for the introduction of nasogastric tube between ventral and common meatus
what are paranasal sinuses?
air filled cavities lined with mucosa in the skull that communicates with the nasal cavities through narrow openings
what is the clinical importance of the paranasal sinuses?
their openings are narrow and prone to clogging
what is the species difference related to the paranasal sinuses?
how the paranasal sinuses are connected to nasal cavity and each other shows species differences
do sinuses participate in respiration?
no
function of the paranasal sinuses?
affect the resonance of the voice; lighten the weight of the skull
heat exchange, sites for mucus secretion
increased insertion space for teeth and muscle
equalise pressure differences within nasal cavity
protection of intracranial structures from trauma
contribute to facial growth
what paranasal sinuses do all domestic species have?
all domestic species have frontal and maxillary sinuses
FRONTAL - dorsal part of the skull between nasal cavity and orbit
MAXILLARY - maxillary bone with nasal cavity on each side
all large farm animals also have which sinuses?
sphenoidal and palatine sinuses
Sphenoidal sinus?
sphenoid bone
palatine sinus?
palatine bone, communicates with maxillary sinus
lacrimal sinus?
swine, ruminants - on lacrimal bone
conchal sinus?
swine, ruminants, equine - formed by enclosure of conchae
type of paranasal sinuses?
frontal, maxillary, sphenoidal, palatine, lacrimal and conchal
where does the frontal sinus occupy in a dog?
it occupies the supraorbital process of the frontal bone
maxillary sinus termed as?
maxillary recess
what are the paranasal sinuses bounded by in a dog?
bounded by ethmoid, maxillary, palatine and lacrimal bones
where is the sphenoid sinus found?
within the presphenoid bone
two sides of frontal sinus are separated by?
by a median septum and divided into rostral, medial and lateral compartments
which animal does not have fully developed sinuses until age seven?
cows
describe the frontal sinus?
it has diverticula for the cornual process
what does the frontal sinus of the cow have?
the frontal sinus has diverticula for the cornual process
maxillary sinus occupies where in cow?
upper jaw dorsal to the alveolar bone
where is the palatomaxillary sinus found within in the cow?
within the caudal part of the hard palate and face
what are the paranasal sinuses of the horse?
rostral + caudal maxillary sinus
ventral conchal sinus
sphenopalatine sinus
frontal sinus
ethmoid labyrinth
frontomaxillary opening
dorsal conchal sinus
infraorbital canal
septum between maxillary sinuses
what are the regions of the pharynx?
oropharynx
nasopharynx
(contains auditory tube opening)
laryngopharynx
what is the pharynx?
common passageway for air and food
openings to pharynx include?
two nares
two eustachian tubes
a mouth
a glottis and an oesophagus
guttural pouch of horses?
paired diverticula of the auditory tubes, each containing 300ml of air
how are guttural pouches of horses separated?
they are in direct contact with each other, separated only by a thin medial septum
which bone forms the medial and lateral guttural pouches?
the stylohyoid bone
how do the guttural pouches communicate with the pharynx?
via the pharyngeal orifice of the auditory tube, covered by a thin fibrocartilage
which animal has a rostral bone?
pigs
what are the regions of the larynx?
musculocartilagenous organ
glottis
organ of phonation
glottis
epiglottis
laryngeal cartilages
mucous membrane covering the ethmoidal conchae contains sensory endings of which nerve?
olfactory
what is the musculocartilagenous muscle?
region of larynx
guarding the entrance to the trache
which meatus is the best way to introduce a nasogastric tube?
ventral/common meatus
organ of phonation?
region of larynx
vocal chords
lies below pharynx
glottis?
region of larynx
slit like openings between the vocal cords
epiglottis?
region of larynx
cranial to glottis - leaf shaped cartilage covered with the mucous membrane
laryngeal cartilages?
epiglottis, thyroid, cricoid, arytenoid (only the arytenoid is paired)
what does the cricoid cartilage mostly do?
preventing collapse or constriction of the laryngeal airway (mostly the cricoid)
what are the muscles of the larynx?
cricoarytenoideus dorsalis
Cricoarytenoideus lateralis
apart from the muscles of the larynx - what else does it consist of?
cricoid cartilage
glottic cleft
thyroid cartilage
describe the Cricoarytenoideus dorsalis:
ABductor
only dilator of the glottis, important in roaring
what movement does the Cricoarytenoideus lateralis do? (larynx)
ADductor
innervation of the laryngeal muscles?
the laryngeal muscles are innervated by cranial and caudal laryngeal nerves (branches vagus nerve)
where does the cranial laryngeal pouch detatch?
at the head/neck junction
where does the caudal laryngeal branch detach?
detaches in the thorax
where does the cranial branch enter the larynx?
enters the larynx by the thyroid foramen but just before gives a branch to cricothyroideus muscle
where does the caudal laryngeal (recurrent laryngeal nerve.) nerve leave?
leaves the vagus in the thorax then ascends through the neck and distributes itself to rest of the laryngeal muscles
what does the right and left recurrent nerve do?
it winds around right subclavian artery while the left one winds around the aorta
