2: Respiratory System Flashcards
What are the 5 functions of the respiratory system?
1) O2 and CO2 exchange
2) olification
3) phonation
4) provide defense
5) condition air
#1 = respiratory portion #2-5 = conducting portion
What are the 3 tiers of the filtration system?
1) large particle filter: bugs
2) medium particle filter: dust, pollen
3) small particle filter: bacteria, viruses
What are the parts of the nasal cavity?
vestibule, respiratory region, olfactory region
What type of surface epithelium is in the nasal cavity of the vestibule?
keratinized stratified squamous ( same as skin)
What glands are in the nasal cavity vestibule?
sebaceous & sweat
What supports the nasal cavity vestibule?
hyaline cartilage
What additional features are in the nasal cavity vestibule?
VIBRISSAE: large particle filter (nose hairs)
Where is the respiratory region of the nasal cavity found?
btwn the limen nasi and superior/middle concha
What are the 4 functions of the respiratory region?
1) warm air
2) clean air
3) humidify air
4) provide defense
What is the surface epithelium of the respiratory region of the nasal cavity?
respiratory (ciliated pseudostratified columnar)
moves mucus
What kind of cells are the mucociliary apparatus of the respiratory area made of?
globlet & ciliated columnar cells = medium particle filter
What does the mucociliary apparatus do?
mucociliary clearance
What type of glads are found in the respiratory region of the nasal cavity?
seromucus glands
Where are the seromucus glands found?
in the lamina propria (LP)
Mucus portion of seromucus glands contributes mucus for what?
1) mucociliary clearance
2) air humidity
Serous products produced by the seromucus gland are what?
1) lysozyme: anti-bacterial
2) interferons: anti-viral
3) cytokines: stimulate defensive cells
4) air humidity
SMALL PARTICLE FILTERS
What else is found in the LP of the respiratory nasal cavity?
cavernous plexus: many large venules; typically partially filled
What are the functions of the cavernous plexus?
1) humidify air
2) humidify air
3) provide defense (ex: inflammation)
What are the side effects of inflammation?
INCREASED BF:
- venules enlarge & LP increases in size, lumen decreases in size = STUFFY NOSE - O2 increases which will stimulate seromucus gland secretion = RUNNY NOSE
What supports 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 w/ supporting & basal cells and olfactory neurons
What do the supporting cells of the surface epithelium of the olfactory region do?
provide physical support, nourishment and electrical insulation for olfactory cells
COLUMNAR CELLS W/ MICROVILLI
What are olfactory neurons?
bipolar neurons w/ olfactory cilia extending onto the epithelial surface.
BASAL AXON: unmyelinated w/ Schwann cells
- passes through the cribriform plate ultimately connecting to the olfactory bulb
What are basal cells?
small phyramidal shaped cells that can divide and replace the other two types of cells
What glands are found in the olfactory region of the nasal cavity?
olfactory (Bowman’s) glands
What do olfactory (Bowman’s) glands do?
produces a serous product to “cleanse” olfactory cilia
What supports the olfactory region of the nasal cavity?
bone
What are the large particle filters of the nasal cavity?
Vibrissa
What are the medium particle filter structures of the nasal cavity?
mucocilliary apparatus or goblet & ciliated columnar cells
What are the small particle filters of the nasal cavity?
seromucus glands = serous portion
Where are the paranasal sinuses found?
ethmoid, sphenoid, frontal, and maxilla bones
What do the paranasal sinuses do?
connect to the nasal cavity through sinal ostia
What type of epithelium lines the paranasal sinuses?
respiratory epithelium
What is the lamina propria of the paranasal sinuses like?
thin but has seromucus glands, quite vascular
What is a possible problem with the paranasal sinuses?
with small ostia, if the LP swells the ostia can become blocked & sinus infection can thrive
What are the 3 subdivisions of the pharynx?
nasopharynx, oropharynx, laryngopharynx (sup-inf)
What is the surface epithelium of the nasopharynx?
respiratory
What is the surface epithelium of the oropharynx?
stratified squamous
What is the surface epithelium of the laryngopharynx?
stratified squamous
Can the LP of the pharynx have tonsils?
yes
What tonsils can the nasopharynx have?
pharyngeal tonsils
What tonsils can the oropharynx have?
palatine & lingual tonsils
What tonsils can the laryngopharynx have?
NONE
Can the muscularis mucosae (MM) have tonsils?
no
What can the submucosa of the pharynx also be called?
pharyngobasilar fascia
What is the structure of the submucosa of the pharynx?
collagen in the periosteum of basilar portion of the occiput blends into the wall of pharynx
What is the function of the submucosa (pharyngobasilar fascia) of the pharynx?
added support
What is the muscularis externa of the pharynx made of?
all skeletal muscle
What is the patterning of the muscluaris externa of the pharynx?
Reversed:
inner longitudinal muscle
outer circular muscular layer
(also occurs in the uterus)
What can the adventitia of the pharynx also be called?
buccopharyngeal fascia
What is the structure of the adventitia of the pharynx?
epimysium of buccinator muscle blends into the adventitia of the pharynx
What is the adventitia?
CT on longitudinal organs
What is the larynx?
an organ lying between the pharynx & trachea
What is the surface epithelium of the luminal wall?
upper surface: stratified squamous
parts will transition to respiratory
What is the LP of the luminal wall structure?
loose CT w/ seromucus glands
What is the function of the cartilages w/i the wall of the larynx?
maintain an open airway
aid sound production (long w/ skeletal muscle)
What are the types of cartilages found w/i the larynx?
hyaline cartilage & elastic cartilage
What parts of the larynx are made of hyaline cartilage?
thyroid, cricoid, & inferior arytenoid cartilages
What parts of the larynx are made of elastic cartilage?
epiglottis, cuneiform, corniculate & superior arytenoid cartilages
What is the general function of the epiglottis?
to keep food & liquid out of the larynx
What is the surface epithelium of the epiglottis?
upper surface: stratified squamous
lower surface: transitions to respiratory
What are the vestibular folds?
immovable folds of tissue
What is the surface epithelium of the vestibular folds?
respiratory epithelium
What is the LP of the vestibular folds?
loose CT w/ seromucus glands & possible lymph nodules
What is the surface epithelium of the laryngeal ventricle?
stratified squamous epithelium
What is the surface epithelium of the vocal cords (folds)?
stratified squamous epithelium
What is the function of the vocal cords?
protect from abrasion and to get some degree of drying of tissues due to the rapid air movement
What is the LP of the vocal folds made of?
dense regular bundles of elastic CT
What is the function of the LP of vocal folds?
supports vocal fold
What does the vocalis muscle do?
creates sound when air vibrates the vocal folds
Where is the vocalis muscle located?
deep to the mucosa
What is the vocalis muscle?
a striated muscle which will adduct to narrow the rima glottidis
What is the surface epithelium of the trachea?
respiratory epithelium
What are the cell types w/i the surface epithelium of the trachea?
30% goblet
30% ciliated columnar epithelium
30% basal
3% brush cells (maybe chemosensory, air quality)
3% serous cells (secretes an unknown product into the lumen)
3-4% DNES (diffuse neuroendocrine cells) (small granule, kulchitsky cells) secrete in LP, likely influences other cells
What is the LP of the trachea like?
loose CT w/ seromucus glands, quite vascular
The muscularis mucosa is ___________ in the trachea?
absent
What does the submucosa of the trachea contain?
hyaline cartilage C ring and blends w/ LP
What is the muscularis externa of the trachea?
made of individual trachealis muscles
What is the adventitia of the trachea made of?
connective tissue (fiberous or adipose)
What are the extrapulmonary bronchi?
includes the primary bronchi, structurally similar to the trachea
What are the structural trends in the bronchi?
Decreases in: amount of cartilage, numbers of glands, goblet cells, height of epithelium
Increases in: smooth muscle, elastic CT
What do the intrapulmonary bronchi include?
secondary & tertiary bronchi
trends continue
What are bronchioles characterized by?
What type of epithelium is in the bronchioles?
ciliated simple columnar/cuboidal cells w/ some goblet cells & Clara cells (can vary some along w/ length)
What are Clara cells?
secretory cells in surface epithelium of bronchoiles
- secrete product to protect epithelium
- produce enzymes, degrade toxins
- regenerate bronchiolar epithelium
- secrete lysozyme
- produce a surfactant type material
- other cells
What do clara cells have?
have short microvilli
What are terminal bronchioles?
last part of the conducting portion of the respiratory system
What is the surface epithelium of the terminal bronchioles?
simple columnar/cuboidal (often some cilia) w/ clara cells
What is the LP of the terminal brochioles?
fibroelastic CT
What type of muscles are in the terminal bronchials?
1-2 layers of smooth muscle
What are the respiratory bronchioles?
1st region of respiratory portion of respiratory system
What is the structure of respiratory bronchioles?
simple cuboidal epithelium w/ Claras & some cilia;
similar to terminal bronchioles w/ some simple squamous epithelium = GAS EXCHANGE POSSIBLE
What is the function of alveolar ducts?
gas exchange
What is the structure of alveolar ducts?
see alveoli
What is the function of alveolar sacs?
gas exchange
What is the structure of alveolar sacs?
see alveoli
What is the general function of alveoli?
gas exchange
What is the structure of alveoli?
MC cell types: alveolar type I, alveolar type II, alveolar macrophages
What are the alveolar type I cells?
AKA: type I pneumocyte
~95% alveolar surface
squamous cell type w/ zonula occludens btwn cells
GAS EXCHANGE
What are the alveolar type II cells?
AKA: type II pneumocyte
most to sides btwn alveoli
What is the general fxn of alveolar type II cells?
stem cell for alveolar type 1&2
produce pulmonary surfactant
produce lysozyme
What are alveolar macropahges?
AKA: dust cells
fxn: clean septal cell walls using phagocytosis also produce ______???
What is the interalveolar septum?
region btwn 2 alveoli
What parts are included in the interalveolar septum?
alveolar types I&II, continuous capillaries, fibroblasts, basal lamina, small amounts of CT w/ many elastic fibers
What is the blood-gas barrier?
region where O2 & CO2 pass btwn the air and blood
Parts of the blood-gas barrier (air to blood)
1) pulmonary surfactant
2) alveolar type I
3) fused basal lamina: shared btwn alveolar type I cells & endothelial cell of capillary
4) endothelial cells of the capillary
THIS IS THE MINIMUM DIFF. DISTANCE ALLOWING MOST EFFICIENT GAS EXCHANGE
What is the pulmonary nerve supply?
Thoracic sympathetic chain ganglia: relax bronchial smooth muscle = bronchiodilation
Sympathetic fibers: paradoxical response of constricting pulmonary BV’s via smooth muscle and tunica media
What does the vagus nerve do?
parasympathetic fibers contract bronchial smooth muscle resulting in bronchoconstriction
What happens with chronic exposure to irritants and metaplasia in the upper respiratory tract?
globlet cell #’s increase = increased mucus
ciliated columnar cell #’s decrease = congestion increase
seromucus glands increase in size = more fluid
a lot of coughing = change from stratified squamous epithelium instead of respiratory epithelium
What is RDS in newborns?
Respiratory distress of the newborn, haline membrane disease
What is the cause of RDS?
too few mature alveolar type II cells
What are the treatments for RDS?
artificial surfactant & CPAP (only a few treatments)
glucocorticosteroids given before birth will induce surfactant production
What is emphysema?
decrease in elastin so decrease in alveolar tissue
reduced surface for gas exchange
irreversible
What are the two common causes of emphysema?
inflammation & genetic condition
What happens with emphysema caused by inflammation?
attracts macrophages & neutrophils, secrete elastase
alpha 1: antityrosine is a protein that protects elastic fibers
alpha 1-AT: produced by hepatocytes
free radicals in cigarrette smoke inactivates alpha 1-AT
What produces alpha 1-AT?
hepatocytes
What happens with genetic emphysema?
hepatocytes produce alpha 1-AT but cannot release it = levels are too low
gene is inherited dominantly
heterozygous - affected some
homozygous - affected greatly
