respiratory-- physiology Flashcards
3 stages of respiration
pulmonary ventilation
external respiration
internal respiration
pulmonary ventilation- the mechanism of breathing
process of moving air (inhalation) out of the lungs (exhalation)
gas travel from an area of high pressure to low pressure
muscles of breathing
what is boyles law
pressure of a gas in a closed container is inversely proportional to the volume of the container
whats average pressure gradient
atmospheric pressure: 760mmHg
intrapulmonary pressure: 760mmHg
intrapleural pressure: 756mmHg
gases will only travel into lungs with intrapulmonary pressure drops
inspiration ……
intercostal muscles:
external intercostals contract pulling the ribs up and out
parietal pleura moves with the thoracic cavity, the visceral pleura follows pulling the lungs with it
diaphragm contracts:
increased volume of pleural cavity
reduced pressure
air moves down the pressure gradient
intrathoracic pressure < atmospheric air
air enters lungs
high compliance ……..
lungs and thoracic cage are easily expanded
low compliance ……
lungs and thoracic cage arent easily expanded
whats laplaces law
the larger the vessels radius, the larger the wall tension required to withstand a given internal fluid pressure
pulmonary ventilation- mechanism of breathing
process of moving air into lungs (inhalation) and out of the lungs (exhalation)
gases travel from an area of high pressure to low pressure
diaphragm and intercostal muscles
tidal volume
500ml at rest
the amount of air passing into and out of the lungs during each cycle of breathing
residual volume
1200ml
cant be measured. volume remained in lungs following forced expiration
expiratory reserve volume
1000-1200ml
largest volume of air that can be expelled during maximal expiration
inspiratory reserve volume
3300ml
this is the extra volume of air that cant be inhaled into lungs during maximal inhalation
inspiratory capacity
amount of air that can be inspired with maximal effort (TV+IRV)
vital capacity
maximal amount of air that can be moved into and put of the respiratory system in a single breath
add all capacity = vc 4800ml
external respiration …..
exchange of gases between the alveoli and the blood in alveolar capillaries across the respiratory membrane
internal respiration ….
exchange of gases between blood in capillaries and the blood cells
gas exchange
gas moves from areas of high pressure to low
same for mixed gases
pressure that each gas exerts to make up the pressure of air is known as gas’s partial pressure
daltons law
diffusion and henrys law
diffusion= movement of a chemical substance from an area of high concentration to low concentration
henrys law= the amount of dissolve gas is proportional to its partial pressure in the gas phase
