Respiratory System Flashcards
What is the respiratory function of the respiratory system?
Oxygen and CO2 exchange
What functions make up the conducting portion of the respiratory system?
Olfaction, phonation, provide defense, condition air
What are the three tiers of the respiratory system?
Large, medium, and small particle filters
What is an example of something that can get stuck in the large particle filter of the respiratory system?
Bug
What are examples of things that can get stuck in the medium particle filter of the respiratory system?
Dust, pollen
What are examples of things that can get stuck in the small particle filter?
Bacteria and viruses
What surface epithelium makes up the nasal vestibule?
Keratinized stratified squamous
What glands in the connective tissue can be found in the nasal vestibule?
Sebaceous and sweat glands
What supports the nasal vestibule?
Hyaline cartilage
What are the additional features seen in the nasal vestibule?
Vibrissae (nose hairs) = large particle filter
Where is the respiratory region of the nasal cavity located?
Between the limen nasi and superior and middle nasal concha
What are the functions of the respiratory portion of the nasal cavity?
Warm air
Clean air
Humidify air
Provide defense
What is the surface epithelium of the respiratory region of the nasal cavity?
Ciliated pseudostratified columnar (made of goblet cells, basal cells, and dilated columnar cells)
What cells is the mucociliary apparatus made of?
Goblet and ciliated columnar cells (medium particle filter)
What type of glands are found in the respiratory region of the nasal cavity?
Seromucus glands
What is the purpose of the mucus of the respiratory region of the nasal cavity?
Mucociliary clearance
Air humidity
In what layer are the glands of the respiratory region located?
Lamina propria
What are the serous products produced in the respiratory region of the nasal cavity?
Lysozymes, interferons, cytokines, air humidity
Lysozymes protect against what substances?
Bacteria
Interferons protect against what substances?
Viruses
What is the function of the cytokines in the respiratory region of the nasal cavity?
Recruit defensive cells
Where is the small particle filter of the respiratory system found?
Respiratory region (serous products)
Where is the large particle filter of the respiratory system found?
Nasal vestibule
Where can the middle particle filter of the respiratory system be found?
Mucociliary apparatus
What else can be found in the lamina propria?
Cavernous plexus - many large venules (usually partially filled)
What are the functions of the cavernous plexus?
Warm air
Humidify air
Provide defense
What is the support for the respiratory region of the nasal cavity?
Hyaline cartilage and bone
What is the surface epithelium of the olfactory region of the nasal cavity?
Olfactory epithelium with supporting and nasal cells, also olfactory neurons
What are the effects of increased blood flow on the venules?
Venules enlarge and lamina propria increases in size
Lumen size decreases and leads to a slight runny nose
What are the functions of the respiratory system?
Oxygen and CO2 exchange Olfaction Phonation Provide defense Condition air
How does increased blood flow affect oxygen levels in the nasal cavity?
Increases oxygen which leads to stimulation is seromucus glands which leads to a more intense runny nose
What kind of epithelium is seen in the paranasal sinuses?
Respiratory epithelium
Where are paranasal sinuses found?
In the ethmoid, sphenoid, frontal, and maxilla bones
How do the paranasal sinuses connect to the nasal cavity?
Sinal ostia
What is the lamina propria like of the paranasal sinuses?
Thin but has seromucus glands and is quite vascular
What is the potential problem with paranasal sinuses?
If small ostia are present, lamina propria can swell and the ostia can become blocked then a sinus infection can thrive
What kind of cells are the supporting cells of the olfactory region of the nasal cavity?
Columnar cells with microvilli
What kind of neurons are olfactory neurons?
Bipolar
Are olfactory axons myelinated?
No but have a layer of Schwann cells
What shape are the basal cells of the olfactory region?
Pyramidal
What glands produce a serous material to cleanse the olfactory cilia?
Olfactory “Bowman’s” glands
What structure provides support in the olfactory region of the nasal cavity?
Bone
What is the surface epithelium of the nasopharynx?
Respiratory epithelium with mucociliary clearance
What is the surface epithelium of the oropharynx?
Stratified squamous
What is the surface epithelium of the laryngopharynx?
Stratified squamous
What are the three parts of the pharynx?
Nasopharynx, oropharynx, and laryngopharynx
What part of the pharynx does not have tonsils?
Laryngopharynx
In what part of the pharynx do we see palatine and lingual tonsils?
Oropharynx
In what part of the pharynx do we see the pharyngeal tonsils?
Nasopharynx
What type of connective tissue makes up the lamina propria of the pharynx?
Loose connective tissue
What is another term for the submucosa of the pharynx?
Pharyngobasilar fascia
What is function of the pharyngobasilar fascia?
Added support
What is the pharyngobasilar fascia?
Collagen in periosteum of the basilar portion of the occiput blends into the wall of the pharynx
What kind of muscle makes up all of the muscularis externa?
Skeletal muscle
What is unique about the muscularis externa of the pharynx?
Reversed pattern of muscle layers
What is the reversed muscle pattern seen in the pharynx?
Inner longitudinal layer and outer circular muscle layer
Where else is the reversed muscular layer pattern seen besides the pharynx?
Ureters
What is another name for the adventitia of the pharynx?
Buccopharyngeal fascia
What is the buccopharyngeal fascia?
Epimysium of buccinator muscle blends into the adventitia of pharynx
What is the function of the adventitia of the pharynx?
Hold pharynx in place
Where is the larynx found?
Between the pharynx and trachea
What is the surface epithelium of the upper surface of the larynx?
Stratified squamous
What makes up the lamina propria of the larynx?
Loose connective tissue with seromucus glands
What are the functions of the cartilage of the larynx?
Maintain an open airway
Aid in sound production (along with skeletal muscle)
What are the two types of cartilage seen in the larynx?
Hyaline and elastic
What is a good classic example of elastic cartilage of the larynx?
Epiglottis
What are the hyaline cartilages of the larynx?
Thyroid, cricoid, and inferior arytenoid cartilages
What are the elastic cartilages of the larynx?
Epiglottis, cuneiform, corniculate, and superior arytenoid cartilages
What is the function of the epiglottis?
Keep food and liquid out of the larynx
What is the surface epithelium of the upper surface of the epiglottis?
Stratified squamous
What is the surface epithelium of the lower part of the epiglottis?
Transitions into respiratory epithelium
What is the surface epithelium of the vestibular folds?
Respiratory epithelium
What is the surface epithelium of the laryngeal ventricle?
Stratified squamous
What is the surface epithelium of the vocal folds?
Stratified squamous
Where is the vocalis muscle located?
Deep to the mucosa
What kind of muscle fibers are seen with the vocalis muscle?
Striated
What is the function of the vocalis muscle?
Adduct to narrow rima glottidis to allow entrance to vibrate vocal folds to produce phonation
What is the surface epithelium of the trachea?
Respiratory
What is the function of the brush cells of the trachea?
Maybe chemosensory
What is the function of the serous cells of the trachea?
Secretion of a product into lumen but the serous product is unknown
Do we see a muscularis mucosa in the trachea?
No (nowhere in the respiratory system)
What layer of the trachea has the hyaline cartilage C ring?
Submucosa
What makes up the muscularis externa of the trachea?
Modified by individual trachealis muscles
What type of muscles are the trachealis muscles?
Smooth
What layer anchors the trachea?
Adventitia (connective tissue)
The extrapulmonary bronchi are similar to what other respiratory structure?
Trachea
What are the structural trends of the bronchi?
Decrease in amount of cartilage, numbers of glands, number of goblet cells, and height of epithelium
What kinds of structures increase in the bronchi?
Smooth muscle and elastic connective tissue
What are the extrapulmonary bronchi?
Primary bronchi
What are the intrapulmonary bronchi?
Secondary and tertiary bronchi
What is the size of bronchioles?
Less than 1mm
What is the epithelium type of bronchioles?
Ciliated columnar with some goblets and Clara cells
What is the only location of Clara cells?
Bronchioles
Bronchioles are characterized by the absence of what kind of tissues and structures?
Cartilage, seromucus glands
What is unique about the smooth muscle in bronchioles?
Complete layer
What are the secretory cells in the surface epithelium of the bronchioles?
Clara cells
What are the functions of the Clara cells of the bronchioles?
Secrete product to protect epithelium
Produce enzymes which degrade toxins
Regenerate bronchiolar epithelium
Secrete lysozyme and produce a surfactant-type material
What is the last part of the conducting portion of the respiratory system?
Terminal bronchioles
What is the epithelium of terminal bronchioles?
Ciliated simple columnar/cuboidal with Clara cells
What makes up the lamina propria of terminal bronchioles?
Fibroelastic connective tissue
What is the muscle portion of the terminal bronchioles?
1-2 layers of smooth muscle
What is the first part of the respiratory portion of the respiratory system?
Respiratory bronchioles
What is the structure of the respiratory bronchioles?
Simple cuboidal epithelium with Clara’s and some cilia in places
What makes respiratory bronchioles different from terminal bronchioles?
Some simple squamous epithelium making some gas exchange possible in the respiratory bronchioles
Which cell type acts as the stem cell for bronchiolar epithelial cells?
Clara cells
What are the functions of Clara cells?
Secrete product to protect epithelium
Produce enzymes to degrade toxins
Regenerate bronchiolar epithelium
Secrete lysozyme and produce surfactant-like material
What is the general function of the alveolar ducts, alveolar sacs, and the alveoli?
Gas exchange
What type of gap junctions are found between the alveolar type I cells?
Zonula occludens
What type of alveolar cell makes up 95% of the alveolar surface?
Alveolar type I
What type of alveolar cell can play a role in respiratory distress syndrome?
Alveolar type II
What is another name for both alveolar type I and alveolar type II cells?
Type I and type II pneumocytes
Which type of alveolar cell is the last to be fully functional in a developing fetus?
Alveolar type II
What is the cell shape of alveolar type II cells?
Cuboidal
What are the general functions of alveolar type II cells?
Produce pulmonary surfactant
Stem cell for alveolar type I and II
Produce lysozymes
What is the general function of alveolar type I cells?
Gas exchange
Which type of alveolar cell produces surfactant?
Alveolar type II
Alveolar macrophages are derived from what cells?
Monocytes
What are the general functions of alveolar macrophages?
Clean septal walls using phagocytosis
Produce lysozymes
Where is the interalveolar septum located?
Between two alveoli
What are the parts of the interalveolar septum?
Continuous capillaries
Basal lamina
Small amount of connective tissue with MANY elastic fibers
Alveolar type I and type II cells
What cell types are seen in the interalveolar septum?
Fibroblasts, myofibroblasts, and mast cells
What is the region where oxygen and carbon dioxide pass between the air and the blood?
Blood-Gas barrier
What are the parts (in order) of the blood-gas barrier?
Pulmonary surfactant
Alveolar type I
Fused basal lamina
Endothelial cells
The fused basal lamina of the blood-gas barrier is between what cell types?
Alveolar type I and endothelial cells in capillaries
What provides the most efficient gas exchange?
Minimum diffusion barrier
What provides fibers that relax bronchial smooth muscle to lead to bronchiodilation?
Thoracic sympathetic chain ganglia
Sympathetic fibers also have an constrictive effect on what layer of the pulmonary blood vessels?
Tunica media (smooth muscle)
What provides fibers that contract bronchial smooth muscle to lead to bronchoconstriction?
Vagus nerve (parasympathetic fibers)
Stimulation of what part of the autonomic nervous system results in bronchial relaxation and bronchiodilation?
Sympathetic
Stimulation of what part of the autonomic nervous system results in bronchial contraction and bronchioconstriction?
Parasympathetic
Which type of alveolar cells appear to synapse with nerve fibers?
Type II
Since alveolar type II cells appear to synapse with nerve fibers, production of what substance could be under neural influence?
Pulmonary surfactant
Why is increased mucus production a result from chronic exposure to irritants of the upper respiratory tract?
Number of goblet cells increased during metaplasia
Why is increased fluid production a result from chronic exposure to irritants of the upper respiratory tract?
Seromucus glands increase in size
Why does congestion increase as a result from chronic exposure to irritants of the upper respiratory tract?
Decreased cilia due to damage, ciliated columnar cell numbers decrease
How does the surface epithelium change during chronic exposure to irritants and coughing in the upper respiratory tract?
Change from respiratory epithelium to stratified squamous (metaplasia)
What is another name for respiratory distress syndrome?
Hyaline membrane disease
What is the cause of RDS in newborns?
Too few mature and functioning alveolar type II cells
Not enough surfactant
How is elastin affected by emphysema?
Decreased (therefore decrease in alveolar elasticity)
How is the surface area for gas exchange affected by emphysema?
Decreased
Is emphysema reversible?
NO
What can cause emphysema?
Inflammation from irritants, infections, smoking
Genetic condition
What is the mechanism of action of inflammation-induced emphysema?
Macrophages and neutrophils are attracted to the area and secrete elastase which destroys elastic fibers
What is the mechanism of action for the genetic condition that causes emphysema?
Hepatocytes produce but cannot release alpha-antitrypsin which is a natural protector of elastic fibers in the lungs; therefore, elastic fibers are destroyed
What is the genetic pattern of the condition that can cause emphysema?
Autosomal dominant: if heterozygous, affected somewhat; if homozygous, affected greatly
What provides fibers that relax bronchial smooth muscle to lead to bronchiodilation?
Thoracic sympathetic chain ganglia
Sympathetic fibers also have an constrictive effect on what layer of the pulmonary blood vessels?
Tunica media (smooth muscle)
What provides fibers that contract bronchial smooth muscle to lead to bronchoconstriction?
Vagus nerve (parasympathetic fibers)
Stimulation of what part of the autonomic nervous system results in bronchial relaxation and bronchiodilation?
Sympathetic
Stimulation of what part of the autonomic nervous system results in bronchial constriction and bronchioconstriction?
Parasympathetic
Which type of alveolar cells appear to synapse with nerve fibers?
Type II
Since alveolar type II cells appear to synapse with nerve fibers, production of what substance could be under neural influence?
Pulmonary surfactant
Why is increased mucus production a result from chronic exposure to irritants of the upper respiratory tract?
Number of goblet cells increased during metaplasia
Why is increased fluid production a result from chronic exposure to irritants of the upper respiratory tract?
Seromucus glands increase in size
Why does congestion increase as a result from chronic exposure to irritants of the upper respiratory tract?
Decreased cilia due to damage
How does the surface epithelium change during chronic exposure to irritants in the upper respiratory tract?
Change from respiratory epithelium to stratified squamous
What is another name for respiratory distress syndrome?
Hyaline membrane disease
What is the cause of RDS in newborns?
Too few mature and functioning alveolar type II cells
Not enough surfactant
How is elastin affected by emphysema?
Decreased (therefore decrease in alveolar elasticity)
How is the surface area for gas exchange affected by emphysema?
Decreased
Is emphysema reversible?
NO
What can cause emphysema?
Inflammation from irritants, infections, smoking
Genetic condition
What is the mechanism of action of inflammation-induced emphysema?
Macrophages and neutrophils are attracted to the area and secrete elastase which destroys elastic fibers
What is the mechanism of action for the genetic condition that causes emphysema?
Hepatocytes produce but cannot release alpha-AT which is a natural protector of elastic fibers in the lungs; therefore, elastic fibers are destroyed
What is the genetic pattern of the condition that can cause emphysema?
Autosomal dominant: if heterozygous, affected somewhat; if homozygous, affected greatly
What are the two treatments for RDS?
Artificial surfactant or gluticosteroids to induce surfactant production
What is the function of alpha 1-antitrypsin?
Protects elastic fibers in the respiratory system
What produces alpha 1-antitrypsin?
Hepatocytes in the liver
How does cigarette smoke affect alpha 1-antitrypsin?
Free radicals inactivate it
