Respiration System Flashcards
ventilation
Exchange of gases between the atmosphere and alveolar gas
diffusion
exchange of gases across the alveolar membrane into the bloodstream or exchange of gases between circulatory system and bloodstream
circulation
exchange of gases between circulatory systems and body cells
external respiration
takes place in lungs, involves the exchange of O2 and CO2 molecule between air and blood
internal respiration
takes place within the body and involves the exchange of O2 and CO2 molecules between the blood and tissue fluids
pleural cavity
membrane surrounding lungs, reduces friction from thoraic cavity (chest cavity)
exhalation
diaphragm and intercostal muscles relax, chest volume decreases. This causes pressure in the lungs to increase (greater pressure in lungs than atmospheric pressure) air moves out
inhalation
diaphragm and intercostal muscles contract, chest volume increases. The pressure in the lungs is lower than atmospheric pressure, air moves into lungs
what % of each gases are inhaled?
O2 = 21%
CO2 = 0.04%
N2 = 78%
what % of each gas is exhaled?
O2 = 16%
CO2 = 5%
N2= 78%
Alveoli
exchange of gases occurs here, one cell layer thick so gases can diffuse easily
tidal volume
amount of air inhaled and exhaled in a normal breath
expiritory reserve volume (erv)
amount of air that can be forcibly exhaled after a normal exhalation
inspiratory reserve volume (irv)
amount of air that can be inhaled after a normal inhalation
vital capacity (vc)
maximum amount of air that can be forcibly exhaled after a full inhalation, calculated from irv, erv, tv (VC= IRV + ERV + TV)
