Gaseous exchange

Cards (11)

when does gas exchange occur?
when alveoli is filled with air
what is gas exchange?
the diffusion of oxygen and carbon dioxide between air in alveoli and blood in capillaries.
what is alveoli surrounded by?
capillaries
what type of walls does alveoli have (adaptation)?
thin moist walls to diffuse through
what is the alveoli’s surface area like (adaptation)?
large (400 mil)
what is an adaptation of the alveoli along with the capillaries?
they’re closely wrapped together creating short distance for diffusion.
what is blood supply like in alveoli?
substantial so gas is carried away quickly
what is diffusion?
movement of gas from area of high to low concentration after inhalation
when does oxygen diffuse from alveoli into blood?
when alveoli has high oxygen concentration but low in blood
when does carbon dioxide diffuse from blood into alveoli? 
when blood has high CO2 concentration but low in alveoli
what happens to gas exchange during exercise?
MORE GAS EXCHANGE TAKES PLACE: muscles use more oxygen. blood returning from muscles has low oxygen concentration. concentration difference between O2 in blood and air in alveoli is bigger. more O2 diffuses into blood. more CO2 created in muscles = high concentration in blood. more CO2 diffuses with air in alveoli.