L16 - alveolar ventilation

Question 1

does gas exchange take place in single unit of alveoli or individual alveolus

Answer 1

individuals one s

Question 2

what’s ficks law

Answer 2

the gases diffuse down their partial pressure gradient

Question 3

what’s the partial pressure graident for oxgyen and CO2

Answer 3

O2- from alveolo to blood

CO2- from blood to alveoli

Question 4

what gas partial pressure is gas exchange dependent on

Answer 4

alveolar gas partial pressure

- that determines the direction of the O2 and CO2 diffusion down their conc gradients

Question 5

will the alveolar gas partial pressure be same for every individual alveoli

Answer 5

different but it becomes an average when it comes to whole lung
-they have different gas compositions since they are in different location in the lung

Question 6

what happens to the partial pressures of the gases during the exchange

Answer 6

will reach EQB no matter the levels of partial pressures in different alveoli

Question 7

factotrs determining alveolar gas partial pressure

Answer 7

• added metabolic gases through ventilation in the alveoli
• the partial pressures of the gases in the blood from metabolism
• both will equalibrate

Question 8

what happens to metabolism if ventilation is increased

Answer 8

met increases by same factor.

• PO2 increases while PCO2 decreases
• this allows the partial pressures of O2 and CO2 to be constant so the levels of the gases remains constant too
• Alveolar partial pressures (PA) is still the same no matter what the increase or decrease

Question 9

if everything remains constant, what will determine the gas levels

Answer 9

ventilation

Question 10

why isnt ventilation the same in different part of the lungs

Answer 10

because there’s different Pdist in diff parts of the lungs

-so there is a greater ven at the base than the apex of the lung