Section 2 Flashcards
What does the conducting portion of the respiratory system function to do?
Carries air to and from the lungs WITHOUT contributing to gas exchange.
What are all the anatomical structures that make up the conducting portion of the respiratory system?
- Paranasal sinuses
- Nose and nasal cavity
- Pharynx
- Larynx
- Trachea
- Primary bronchi
- End of the conducting portion
What are the paranasal sinuses/what are they used in?
- The paranasal sinuses are a collection of air filled spaces within the bones of the skull communicating with the nasal cavity
- Aid in the conditioning of air (warming and humidifying), defence against pathogens, and act as resonance chambers for speech as well
Which bones contain paranasal sinuses?
The paired sinuses are named after the bones of the skull that contain them:
- frontal sinus (2)
- maxillary sinus (2)
- ethmoid sinus (2)
- sphenoid sinus (2)
What are the paranasal sinuses lines with, and what does this contribute to?
- Lined with respiratory tract epithelium
- Contributes to its function in defense and conditioning
*interesting fact
What happens when epithelial lining of the sinuses becomes inflamed or swollen due to infection?
Pressure can build up due to blockage of mucus flow, which can result in a sinus cold or a headache!
Describe the first line of defence against invading pathogens and debris.
- The nose and nasal cavity
- Traps pathogens and debris in coarse hairs and mucus
- Air enters the vestibules (openings) of the nostrils and is passed into the nasal cavity where it is conditioned
What are the nasal cavity boundaries?
The nasal cavity is surrounded by bony structures that create the boundaries of the cavity:
- Roof (ethmoid bone)
- Floor (hard palate/roof of mouth)
- Medial wall (nasal septum)
- Lateral wall (contains nasal conchae)
- Anterior (nares/opening between nose and nasal cavity)
- Posterior (opening to nasopharynx (choanae))
What is the bone of the roof of the nasal cavity?
A bone in the skull called the ethmoid
What is the bone of the floor of the nasal cavity?
The floor is composed of the hard palate (roof of mouth)
What does the medial wall of the nasal cavity make up?
Makes up the nasal septum.
The septum is composed of the vertical bones in the skull, and separates the two halves of the nasal cavity.
What do the lateral walls of the nasal cavity contain?
- Contains structures called nasal conchae
- These structures create turbulence in the air as it passes through the cavity
- This allows for conditioning and catching debris
What is the anterior border of the nasal cavity made by?
- made by the nares (this is the opening between the nose and nasal cavity)
What is the posterior border of the nasal cavity?
- The opening to the nasopharynx (choanae), where the nasal cavity connects to the pharynx
*note: nasal conchae and nasal choanae are SEPARATE structures, don’t get them confused!!
What type of epithelium is the nasal cavity mostly covered in? And why?
- respiratory tract epithelium (RTE)
- because of its role in protection from airborne debris and microorganisms, as well as the conditioning of air
What type of epithelium is the roof of the nasal cavity lined with?
Olfactory epithelium, which contains sensory receptors for smell