Chapter 22 - respiratory system Flashcards
What are the 4 things the respiratory system is responsible for and where do they function?
- pulmonary ventilation (moving air in and out of lungs)
- pulmonary gas exchange (of O2 and CO2 between lungs and blood)
- transport respiratory gases (O2 and CO2 in blood)
- tissue gas exchange (O2 and CO2 between blood and tissues)
- in olfaction and speech
What is the major organs in the upper respiratory system?
- nose and paranasal sinuses
- pharynx
What is the major organs in the lower respiratory system?
- larynx
- trachea
- bronchi and their smaller branches
- lungs and alveoli
What is the respiratory muscles classified with?
muscular system
Describe the function of the nose.
- produces mucus
- resonance chamber for speech
- receptors for sense of smell
Describe the function of the paranasal sinuses.
- lighten skull
- filters air
Describe the function of he pharynx and the common name.
- passageway for air and food
- connects nasal cavity to larynx and mouth to esophagus
- facilitates exposure of immune system to inhaled antigen
- throat
Describe the function of the larynx.
connects pharynx to trachea (cartilage and dense connective tissue)
- airway passage
- prevents food from entering lower reparatory
- voice production
Describe the function of the trachea.
flexible tube running from larynx and divides 2 main bronchi
- airway passage
- cleans, moistens, warms incoming air
Describe the function of the bronchial tree.
contains right and left bronchi (lack cartilage but has smooth tissue)
- connects air from trachea with alveoli
- cleans, moistens, warms incoming air
Describe the function of the alveoli.
termini of bronchial tree (made of simple squamous epithelium with thin basement membrane)
- main site for gas exchange
- surfactant reduces surface tension (prevents alveolar collapse)
Describe the function of the lungs.
in the mediastinum in thorax (stroma is elastic connect tissue)
- respiratory passages smaller that the main bronchi
Describe the function of the pleurae.
serous membrane - lines thoracic cavity
- produces lubricating fluid and compartmentalize lungs
What are the two regions of the nose?
- External nose
- Nasal cavity
What are the surface features of the external nose?
- Root: Area between eyebrows.
- Bridge: The upper part of the nose.
- Dorsum nasi: Anterior margin of the nose.
- Apex: Tip of the nose.
- Nostrils (nares): External openings of the nose, bounded laterally by alae.
What is the skeletal framework of the external nose?
- Nasal and frontal bones superiorly: Form the bridge and root.
- Maxillary bones laterally: Form the sides of the nose.
- Plates of hyaline cartilage inferiorly: Includes alar and septal cartilages.
Where is the nasal cavity located and how is it divided?
- within and posterior to the external nose
- the midline nasal septum
What structures form the nasal septum?
- anteriorly by septal cartilage
- posteriorly by the vomer bone and perpendicular plate of the ethmoid bone
What are the posterior nasal apertures (choanae)?
openings that allow air to pass from the nasal cavity into the nasopharynx
What forms the roof of the nasal cavity?
the ethmoid and sphenoid bones
What forms the floor of the nasal cavity?
Hard palate (bone)
Soft palate (muscle)
What is the nasal vestibule?
is part of the nasal cavity located superior to the nostrils and is lined with vibrissae (hairs) that filter small particles from inspired air.
What lines the rest of the nasal cavity?
- olfactory mucosa: lines superior region and contains olfactory epithelium
- respiratory mucosa: line most of the cavity and contains:
- pseudostratified ciliated columnar epithelium with goblet cells
- lamina propria with seromucous nasal glands
What is the function of the respiratory mucosa?
- cilia that sweeps contaminated mucus posteriorly towards the throat
- seromucous nasal glands, which secrete:
- mucous cells
- serous cell (watery with enzymes)
What is the function of the mucosa’s sensory nerve endings?
trigger the sneeze reflex to remove irritants
How is inspired air treated in the nasal cavity?
warmed by plexuses of capillaries and thin-walled veins in the mucosa
What are the nasal conchae and how are they divided?
scroll-like, mucosa-covered projections that protrude medially from the lateral walls of the nasal cavity
1. superior concha
2. middle concha
3. inferior concha
What is the function of the nasal conchae?
- the shape increases the mucosal area exposed to air and enhances turbulent airflow
- helps trap more air particles in mucus, improving air cleaning
What happens during inhalation and exhalation regarding the conchae?
- During inhalation, conchae and nasal mucosa filter, heat, and moisten the air.
- During exhalation, conchae and mucosa reclaim most of the heat and moisture.
What are paranasal sinuses?
- air-filled spaces within the frontal, sphenoid, ethmoid, and maxillary bones that surround and connect with the nasal cavity.
How do sinuses drain?
Blowing the nose creates suction that helps drain the paranasal sinuses
What type of muscle makes up the wall of the pharynx?
contains skeletal muscle along its length, from the base of the skull to the C6 vertebra
Into how many regions is the pharynx divided?
- Nasopharynx
- Oropharynx
- Laryngopharynx
How does the mucosal epithelium vary in the pharynx?
based on region
Where is the nasopharynx located?
is posterior to, and continuous with the nasal cavity
What type of epithelium lines the nasopharynx?
pseudostratified ciliated columnar epithelium that propels mucus inferiorly
What is the primary function of the nasopharynx?
The nasopharynx serves only as an airway
How does the nasopharynx function during swallowing?
the soft palate and uvula move superiorly to close off the nasopharynx
What structures are located in the posterior wall of the nasopharynx?
contains the pharyngeal tonsils (also known as adenoids).
How are the lateral walls of the nasopharynx connected to the middle ear?
are connected to the middle ear by the pharyngotympanic (auditory) tubes
What is the function of the pharyngotympanic tubes and what protects the entrance?
drain the middle ear and allow pressure to equalize with atmospheric pressure
- tubal tonsils
What is a swollen adenoid?
- infection can block air passage in nasopharynx (breath through mouth)
- can disrupt speech and sleep
Where is the oropharynx located and its function?
- posterior to, and continuous with, the oral cavity
- passageway for food and air from the level of the soft palate to the epiglottis
What is the archway between the oropharynx and the oral cavity called?
isthmus of fauces
What type of epithelium lines the oropharynx?
protective stratified squamous epithelium.
Where are the palatine tonsils located?
in the lateral walls of the oropharynx, posterior to the oral cavity
What is the location of the lingual tonsil?
the posterior surface of the tongue
Where is the laryngopharynx located and its function?
- posterior to the larynx
- passageway for both food and air
What type of epithelium lines the laryngopharynx?
stratified squamous epithelium
How far does the laryngopharynx extend?
to the bottom of the larynx, where it is continuous with the esophagus