Nasal Cavity, Paranasal Sinuses, Nasopharynx Flashcards
What is respiration?
Exchange of oxygen from environment to cells for utilisation and removal of CO2
3 stages of gas exchange?
1= ventilation (moving gas to site of exchange)
2= gas exchange (capillary beds at lungs and tissues)
3= cellular respiration (cells use oxygen in biochemical processes)
What are the 8 functions of the respiratory system?
- warm, humidify and filter inhaled air
- pH balance
- primarily gas exchange
- speech/vocalisation
- protect and maintain itself from the rest of the body
- prostaglandin synthesis
- metabolic function (angiotensin 1 to angiotensin 2)
Why is there a thin walled and a selectively permeable membrane in the respiratory system?
To facilitate diffusion
What does the moist membrane help to facilitate?
Oxygen and co2 can be dissolved in water to facilitate diffusion
Describe how/why the system work autonomously?
- effective monitoring and feedback mechanisms
- has to be able to do so it can function voluntarily for desired increased and decreased rates
Conducting portion of the respiratory system?
- nose
- nasal cavity
- parasternal sinus
- pharynx
- larynx
- trachea
- bronchi
- bronchial trees
- terminal bronchials
Respiratory portion?
- respiratory bronchioles
- alveoli (ducts and sacs)
How are the alveoli made for optimal gas exchange?
- 400 million per lung
- large surface area
- rich vascular supply
What makes up the upper respiratory tract?
1) nose (nasal cavity)
2) nasopharynx
What makes up the lower respiratory tract?
1) larynx
2) trachea
3) bronchial tree
4) alveolar ducts
5) alveolar sac
6) pulmonary alveoli
What is the nasal cavity held open by?
Held open by a box made of bone and cartilage (osteocartilaginous)
Why is bone needed to hold the nasal cavity open?
Because the decreasing intrathoracic pressure on inhalation would result in the nasal cavity closing if it was held open by cartilage
What are the anterior openings supported by?
Cartilage
What are the 3 muscles around the nostrils (nasal muscles)?
1) procerus
2) nasalis
3) levator labii superioris alaeque nasi
What is the functions of the nasal muscles?
1) acts as sphincters or dilators
2) controls the diameter of the nares and adjusts air flow
THEY ARE MUSCLES OF FACIAL EXPRESSION
What are the nasal muscles innervated by?
Facial nerve
Where is the nasal vestibule?
Immediately after passing the nostrils
What is the nasal vestibule lined with?
Squamous mucosa Epithelium which has VIBRISSAE
Function of vibrissae
First air filters in the respiratory system
The nasal vestibule is at risk of what?
Nasal vestibulitis caused by S.aureus
What does the nasal septum act as?
What does the nasal septum consist of?
1- acts as a medial wall in the nasal cavity, diving it into right and left nasal fossa
2- the nasal septum consists of bone posterior lay and cartilage anterior lay
What are the 2 bones of the septum?
Vomer and ethmoid
Describe the position and nasal cavity is covered in?
It is posterior to the nose and the bony structures are converted in respiratory mucosa
Floor of the nasal cavity made from?
Hard and soft palate
Lateral wall of the nasal cavity is made from what?
- Ethmoid
- superior and middle conchae
- inferior nasal conchae
- maxilla
- sphenoid
- palatine bone
- lacrimal
- nasal bone
What is hard palate made from?
Palatine process maxilla
Horizontal plate of palatine bone
What are the 4 bones of the roof of the nasal cavity?
What mucosa is on the nasal cavity?
1- nasal bone
2- frontal bone
3- ethmoid bone
4- sphenoid bone
Specialised olfactory mucosa
What are the 2 bones of the floor of the nasal cavity?
1- palatine bones
2- maxilla bone
THESE MAKE UP THE HARD PALATE
What makes up the roof of the mouth
Frontal bone
Ethmoid bone
Cribiform plate
sphenoid
Specialised olfactory mucosa
What makes up the medial wall of the nasal cavity?
- septal cartilage
- ethmoid (perpendicular plate)
- vomer
What is the structure called in the middle of the ethmoid bone?
Cribiform plate
- civ like
- this is how the olfactory nerves go from the anterior cranial fossa to the nasal cavity.
What are nasal conchae?
They are pairs of bones that project from the lateral wall of the nasal cavity like shelves
What do conchae produce/
Passages between the inferior surface of the concha and the lateral wall called the meatus.