Exam 4 Flashcards
function of the respiratory system
supply the body with oxygen/dispose of carbon dioxide
sound/voice production
regulation of plasma ph
removal/destruction of airborne pathogens and toxins
name and describe the processes that define respiration
1 pulmonary ventilation - breathing
2 external respiration - O2 loading/CO2 unloading (occurs in lungs)
3 transport - via blood circulation
4 internal respiration - O2 unloading/CO2 loading (occurs in tissues)
describe the pharyngotympanic tubes
aka eustachian tubes
location: above the nasopharynx
pharyngeal tonsil
aka adenoid
above the pharyngotympanic tube
describe the nasal cavity
bottom - palate - separates from oral cavity
hard palate - maxilla and palatine bones
soft palate - muscle
middle (above nostrils) - nasal vestibule
lined with vibrissae - hairs that filter coarse debris
top (rest of cavity) - nasal conchae - lined with mucous membranes
superior, middle, and inferior
*olfactory mucosa: superior; smell receptors
* respiratory mucosa - pseudostratified ciliated columnar epithelium with goblet cells (mucus)
describe paranasal sinuses
open areas in bones that surround the nasal cavity
lighten the skull
help to warm and moisten the air
sinusitis
inflamed sinuses - can lead to blocked passageways that lead from the sinus to the nasa
which bronchus is more vertical?
right primary bronchus
*therefore, inhaled objects tend to get lodged here
describe type 1 cells
simple squamos
form a part of the respiratory membrane that gases diffuse across
gas exchange occurs via simple diffusion/movement from high concentration to low concentration
describe type 2 cells
secrete a lipoprotein (surfactant!) that coats the gas exposed alveolar surfaces
it interferes with the cohesiveness of water molecules which reduces the surface tension of alveolar fluid
describe the visceral and parietal pleuras
visceral: touching the lungs
parietal: lining the outside of the lungs
describe intrapleural and intrapulmonary pressures
intrapleural (outside of lung): 756 mmHg ( -4 mmHg)
intrapulmonary/intra-alveolar (inside of lung): 760 mmHg (0 mmHg)
if the pressures are equal, it leads to atelectasis (lung collapse)
pneumothorax
air in the pleural cavity
describe diaphragm contraction and relaxation
contraction: inspiration
relaxation: expiration
describe expiration
passive process (except for forced expiration)
relaxation of inspiratory muscles
depends on elasticity of lungs (recoil)
alveoli size decreases to smallest diameter , but does not stick together or collapse because of surfactant
describe the respiratory volumes
inspiratory reserve volume (forcefully inhaled) - 3100
tidal volume (normal breathing) - 500ml
expiratory reserve volume (forcefully exhaled) -1200 ml
residual volume (air remaining in lungs after forced expiration) - 1200 ml
boyle’s law
the relationship between the pressure and volume of gases
when the lung volume changes, the pressure in the lungs change
when temperature is constant, pressure is inversely related to volume
dalton’s law of partial pressure
the total pressure (760 mmHg) exerted by a mixture of gases is the sum of the pressures exerted independently by each gas in the mixture
partial pressure
the pressure exerted by each gas
henry’s law
when a gas is in contact with a liquid, the gas will dissolve in the liquid in proportion to its partial pressure
*gases move into/out of liquids until equilibrium is attained
describe carbon dioxide transport
70% transported as HCO3- (bicarbonate) in plasma
20% bound to globin of Hb (carbaminohemoglobin)
10% dissolved in blood
*crabon dioxide diffuses into RBCs and combines with water to form carbonic acid which quickly dissociates into hydrogen ions and bicarbonate ions
haldane effect
decreased oxygen saturation allows more carbon dioxide to enter and be carried within a red blood cell
carbonic anhydrase
enzyme that converts CO2 and H2O to carbonic acid
chloride shift
outrush of negative bicarbonate ions from the RBCs is balanced as chloride ions move in from the plasma
