respiratory physiology 4 - 5

Question 1

define ventilation

Answer 1

air getting into the alveoli (L/min), how much air can engage in gas exchange

Question 2

define perfusion

Answer 2

local blood flow through pulmonary circulation (L/min)

Question 3

where in the lung is blood pressure higher than ventilation and why?

Answer 3

at the base of the lungs, this is because arterial pressure exceeds alveolar pressure, thus compresses the alveoli as these blood vessels press more on them

Question 4

where in the lung is arterial pressure less than alveolar pressure?

Answer 4

at the apex of the lungs, this is because the arterioles are compressed, so alveoli compress the capillaries

Question 5

at what rib does ventilation and perfusion roughly match each other?

Answer 5

rib 3