exam 2 Ch 17

Question 1

two major functions of pulmonary diffusion

Answer 1

replenishes blood oxygen supply
removes carbon dioxide from blood

Question 2

at rest how much blood do lungs receive

Answer 2

4-6 L blood/min

Question 3

lung mean arterial pressure at rest

Answer 3

15 mmHg

Question 4

Why do the lungs have a small pressure gradient

Answer 4

they have thinner vessel walls

Question 5

Standard atmospheric pressure

Answer 5

760 mmHg

Question 6

Daltons law

Answer 6

total air pressure = PN2 + PO2 + PCO 2

Question 7

AIr percentages

Answer 7

N2 = 79.04%
O2 = 20.93
CO2 = 0.03%

Question 8

Total in standard atmosphereic P
N2
O2
CO2

Answer 8

N2 - 600.7 mmHg
O2 - 159.1 mmHg
CO2 - 0.2 mmHG

Question 9

Gases dissolve in liquids in proportion to partial P
Depends on temp
Solubility in blood is constant at given temp

Answer 9

Henrys Law

Question 10

Most importatn factor for determing gas exchange
drives gas diffusion

Answer 10

partial pressure gradient

Question 11

PO2 gradient across respiratory membrane

Answer 11

65 mmHg

Question 12

Rate of diffusion is proportional to surface area and partial pressure gas gradient

Answer 12

Flicks law

Question 13

PCO2 gradient

Answer 13

6 mmHg

Question 14

Does CO2 diffuse easier despite lower gradient

Answer 14

yes

Question 15

O2 diffusion capacity

Answer 15

O2 volume diffused per min per mmHg of gradient

Question 16

Resting O2 diffusion capacity

Answer 16

231 mL O2 / min for 11 mmHg gradient

Question 17

As venous O2 decreases what happens

Answer 17

PO2 bigger gradient
Diffusion capacity increases by 3 times resting rate

Question 18

At rest how much of the lung is getting blood flow for lung perfusion

Answer 18

only bottom 1/3 of lung (because of gravity)

Question 19

What happens to lung perfusion during exercise

Answer 19

systemic blood pressure increases which opens up 2/3 perfusion

Question 20

Pulmonary artery PCO2
Alveolar PCO2

Answer 20

46 mmHG
40mmHG

Question 21

How much greater is the CO2 diffusion constant compared to O2

Answer 21

20 times