Gas exchange

Question 1

What portion of the respiratory tract does dry air go through?

Answer 1

the conducting portion

Question 2

What happens to dry air in the conducting portion of the respiratory tract?

Answer 2

it is warmed and humidified

Question 3

Where does the exchange of O2 and CO2 occur?

Answer 3

at the alveolar respiratory membrane

Question 4

How do gas molecules move?

Answer 4

by diffusion via kinetic motion

Question 5

Does the kinetic motion by which gas molecules move change?

Answer 5

yes, at -273 degrees celcius

Question 6

In what direction does gas movement go?

Answer 6

from higher concentration to lower concentration

Question 7

What is partial pressure determined by?

Answer 7

concentration and solubility

Question 8

Explain Dalton’s law of partial pressures?

Answer 8

the pressure of a mixture of gases is the sum of the pressures of individual components

Question 9

How is pressure affected at higher altitudes?

Answer 9

it is lower

Question 10

What pressure reduces PO2?

Answer 10

vapor pressure

Question 11

CO2 is __ times more soluble than O2

Answer 11

24

Question 12

What is Ficks law of diffusion of gases?

Answer 12

Vgas = (A x D(P1-P2))/ T

Question 13

What is P1 in Ficks law of diffusion of gases?

Answer 13

O2 on the alveolar side (altitude)

Question 14

What is P2 in Ficks law of diffusion of gases?

Answer 14

O2 on the capillary side

Question 15

What is D in Ficks law of diffusion of gases?

Answer 15

diffusion co-efficient

Question 16

What is T in Ficks law of diffusion of gases?

Answer 16

thickness of the membrane

Question 17

In emphysema, the area is reduced, why is this bad?

Answer 17

because there is a smaller area for oxygenation

Question 18

Does thickness affect CO2’s diffusion?

Answer 18

no, because it diffuses 20 times faster than O2

Question 19

Explain Henry’s law of gas diffusion.

Answer 19

the basis of getting N2 dissolved into the blood under higher pressure

Question 20

What is the equation for Henry’s law of gas diffusion?

Answer 20

Cx=Px X Beta x

Question 21

What is the clinical application of Henry’s law of gas diffusion?

Answer 21

scuba diving and N2 narcosis

Question 22

Why is hyperbaric oxygen therapy beneficial?

Answer 22

the atm is higher to allow for more O2 absorption

Question 23

Why is air humidified?

Answer 23

for saturation

Question 24

What happens to PH20 and P1O2 when temperature increases?

Answer 24

PH2O increases and P1O2 decreases

Question 25

Where does O2 diffuse from and to?

Answer 25

alveolus to the red blood cell

Question 26

Where does CO2 diffuse from and to?

Answer 26

red blood cell to the alveolus