Structure of the Airway Flashcards
What is the definition of respiration?
Providing oxygen to the body and removing carbon dioxide through inhalation and exhalation
Ways you can increase the size of the thorax for inhalation?
Contraction of the diaphragm and raising the ribs
Creating a negative intra-thoracic pressure that sucks air through the conductive passages into the lungs
What are the components of the conductive passages?
Nasal cavity
nasopharynx
larynx
Bronchi
In what condition must air be in when it reaches the lungs?
Warmed, filtered and humidifed- achieved by vascular mucosa, cilia and mucus
How is exhalation achieved?
By decreasing the size of the thorax usually in a passive process (as no muscles are contracting so therefore no energy being expended)
What is the structure that marks entry to the nasal?cavity?
Nares
What holds the nasal cavities open?
Bone and cartilage
Where are the nasal cavities found?
Above the oral cavity, between the 2 orbits, posterior to the nose, and anterior to the nasopharynx
What lines the nasal cavities?
A highly vascularised mucosal membrane lined by respiratory epithelium
What composes the respiratory epithelium?
pseudostratified, ciliated, columnar, interspersed with goblet cells that secrete mucous
What is the nasal septum?
Mid-line cavity that separates right and left nasal cavities
What makes up the nasal septum?
Anteriorly it is made up of septal cartilage
Posteriorly it is made up of bone
What can happen if the septum is deviated from the midline?
Sinus drainage may be compromised and can predispose to sinusitis
What are the boundaries of the nasal cavities?
Nasal septum- medially
Soft and hard palates- floor
Nasal concae- laterally
Bone: frontonasal, ethmoid, sphenoid bone- roof
Where is the olfactory epithelium restricted to?
The roof and adjacent lateral wall of the nasal cavities
What are the 3 nasal conchae and what is its function?
Superior, middle and inferior
Provide turbulence and increase surface area for air flow and heat exchange, this helps humidify and moisten air as it enters the body
What is found under each concha and what is its function?
A meatus which works in communication between the sinuses and the nasal cavities
What structures makes up a nasal cavity?
Septum
Lateral walls with conchae
Meati
Airway
What do sinuses do?
Increase air space for breathing, moistening and humidifying air
What are sinuses?
Empty spaces in head, reduces the weight of the skull significantly
Where are orbits found?
Immediately lateral to nasal cavity
Where is the opening of the maxillary sinus found?
High in its medial wall