ch.22-respiratory Flashcards
What type of muscle is responsible for the control of the respiratory system?
skeletal
What are the top 5 functions of the respiratory system?
- gas exchange
- regulating pH
- voice production
- olfaction
- protection
What enters and leaves the body during gas exchange?
oxygen enters blood, CO2 leaves
What is the relationship between CO2 and pH?
increasing CO2 decreases pH making it more acidic
What occurs if you increase H+ ions?
pH decreases making it more acidic
How does smell occur?
airborne molecules are drawn into the nasal cavity
What are the functional divisions of the respiratory system?
conducting and respiratory
conducting division
passages serve mainly for airflow, nostrils to bronchioles
respiratory division
have alveoli for gas exchange
What are the anatomical divisions of the RS?
upper and lower respiratory tract
upper respiratory tract
organs in head and neck, nose through larynx, pharynx
lower respiratory tract
organs of the thorax, trachea through lungs,
larynx, bronchi, bronchioles, lungs
vestibule
inside nares
hard palate
floor of nasal cavity
nasal septum
portion dividing the nasal cavity, made of hyaline cartilage
conchae
bony ridges on lateral walls w/ meatures between, ensure that inspired air comes into contact w/ mucus
functions of nasal cavity
- passageway of air
- cleans the air w/ cilia and mucus
- humidifiers air
- smell
- resonating chambers for speech
pharynx
connects nose and mouth to larynx and esophagus
nasopharynx
air
oropharynx and laryngopharynx
air and food
larynx
voice box
What are the unpaired cartilages of the larynx?
thyroid, cricoid, epiglottis
thyroid cartilage
largest, Adams apple
cricoid cartilage
inferior voice box
epiglottis
flap that closes to prevent choking
What are the paired cartilages of the larynx?
arytenoid, corniculate, cuneiform
arytenoids
determine length of vocal folds
functions of the larynx
-maintain an open passageway for air movement
-prevent swallowed materials from moving into larynx by way of vestibular folds
-sound production
vocal folds
important for producing sound
trachae
supported by hyaline cartilage
respiratory zone
site of gas exchange, have macrophages instead of cilia
What are the 3 types of cells in the respiratory membrane?
type 1 and 2 pneumocytes, dust cells
type 1 pneumocytes
forms 90% of alveolus surface, gas exchange
type 2 pneumocytes
produce surfactant
hilus
where bronchi and blood vessels enter the lung
Pathway to the trachea
nasal cavity, pharynx, larynx, trachea
What are the muscles needed for inspiration?
diaphragm
external intercostals
pectoralis minor
scalenes
quiet inspiration
accounts for 2/3 of increase in size of thoracic volume
What muscles depress the ribs and sternum for expiration?
abdominal muscles
internal intercostals
quiet expiration
relaxation of diaphragm and external intercostals w/ contraction of abdominal muscles
visceral pleura
lines the outside of the lungs
parietal pleura
line the chest cavity
pleural cavity
filled w/ pleural fluid
What are the functions of parietal/pleural fluid?
reduce friction
create a pressure gradient
compartmentalization
What are the structures included in the pulmonary circulation blood supply?
pulmonary arteries and veins
pulmonary arteries
deliver systemic venous blood
pulmonary veins
carry oxygenated blood from respiratory zone to the heart
What are the structures in the systemic circulation blood supply?
bronchial arteries and bronchial veins
bronchial arteries
provide oxygenated blood to lung tissue
What are the two phases of pulmonary ventilation?
inspiration and expiration
inspiration
gases flow into the lungs
thoracic volume increases
intrapulmonary volume increases but the pressure drops
atmospheric pressure is less than intrapulmonary pressure
expiration
gases exit the lungs
intrapulmonary volume decreases, but the pressure increases
greater atmospheric pressure
atmospheric pressure
pressure exerted by the air surrounding the body
intrapulmonary pressure
pressure in alveoli
increases w/ expiration, decreases w/ inspiration
-lung volume increases
intrapleural pressure
pressure in pleural cavity
always negative
makes sure that lungs remain open
What forces promote lung collapse?
elastic recoil of lungs decrease size and surface tension of alveolar fluid
What forces prevent lung collapse?
elasticity of the chest wall
transpulmonary pressure
intrapulmonary pressure - intrapleural pressure
The greater the transpulmonary pressure….
the larger the lungs
pneumothorax
presence of air in the pleural cavity
What occurs if outside pressure is greater than alveolar pressure?
air flows into the alveoli
What is the relationship between pressure and volume?
inversely proportional
as volume increases, pressure decreases and vice versa
What occurs as a result of pressure differences?
gases move
Why is resistance in the respiratory system insignificant?
because of the large airway diameters and progressive branching
What happens as airway resistance rises?
breathing becomes harder
pulmonary compliance
the ease with which lungs can be inflated
affected by surface tension and the elastic properties of lungs
surface tension
thin film of water necessary for gas exchange and creates surface tension that acts to collapse alveoli
What effect does surface tension have on lung compliance?
decreasing surface tension increases lung compliance
surfactant
decreases surface tension
What 3 factors influence pulmonary ventilation?
airway resistance, alveolar surface tension, lung compliance
