Gas exchange

Question 1

movement of gases bw two compartments

Answer 1

gas exchange

Question 2

what are the two locations where gas exchange occurs?

Answer 2

respiratory membrane and systemic capillary wall

Question 3

in the respiratory membrane, the gases move between what locations?

Answer 3

alveolar air and the plasma in the pulmonary circuit

Question 4

in the systemic capillary wall, gases move between what locations?

Answer 4

plasma and ISF in the systemic circuit

Question 5

gases move across barriers by

Answer 5

simple diffusion

Question 6

gas exerts its pressure independently of other gases, and gas press is proportional to temp and concentration

Answer 6

dalton’s law

Question 7

pressure exerted by a gas is called

Answer 7

partial pressure (Px)

Question 8

what is the formula for partial pressure?

Answer 8

Px=Fx(Ptot)

Question 9

during gas exchange, each gas will move down its partial pressure gradient from…

Answer 9

higher to lower pressure

Question 10

if the partial pressure is the same in two compartments, then the partial pressure is..

Answer 10

at equilibrium = no net movement bw compartments

Question 11

movement down a partial pressure gradient can occur from several mediums like what?

Answer 11

from a gas to a liquid, from a liquid to a gas, and from one liquid to another

Question 12

what is typical resting Po2 and Pco2 within the alveolar air?

Answer 12

100mmHg and 40mmHg

Question 13

plasma entering a pulmonary capillary has a typical Po2 and Pco2 of

Answer 13

40mmHg and 46mmHg

Question 14

the partial pressure gradient for O2 favors what movement?

Answer 14

movement of O2 from alveolar air to plasma

Question 15

the partial pressure gradient for CO2 favors what movement?

Answer 15

movement of CO2 from plasma to alveolar air

Question 16

diffusion of gases across the respiratory membrane is _______, and the alveolar air and plasma reach ___________ before blood exits pulmonary capillary.

Answer 16

rapid; equillibrium

Question 17

plasma exiting the pulmonary capillary had a Po2 and Pco2 of what?

Answer 17

100mmHg and 40mmHg

Question 18

what kind of gas exchange occurs before blood enters the systemic capillaries?

Answer 18

none

Question 19

plasma entering a systemic capillary has a typical Po2 and Pco2 of

Answer 19

100mmHg and 40 mmHg

Question 20

ISF will have a ________ value for Po2 and _________ value for Pco2. why is that?

Answer 20

lower; higher; cells take up o2 from the ISF and excrete co2 into the ISF (amount depends on metabolic activity of the cells)

Question 21

what is a typical Po2 and Pco2 for ISF?

Answer 21

40 and 46 mmHg

Question 22

the partial pressure gradient for o2 in the systemic capillaries favors

Answer 22

movement from plasma to ISF

Question 23

the partial pressure gradient for co2 in the systemic capillaries favors

Answer 23

movement from ISF to plasma

Question 24

plasma exiting the systemic capillary has a Po2 and Pco2 of

Answer 24

40mmHg and 46mmHg

Question 25

alveolar air has a _______ Po2 and a ________Pco2 than the atmosphere

Answer 25

lower; higher

Question 26

dry air has a Po2 and Pco2 of what?

Answer 26

160 and 0.3 mmHg

Question 27

what are the factors that determine the value of alveolar Po2 and Pco2?

Answer 27

Po2 of the atmosphere, the rate of alveolar ventilation, and the rate of total body O2 consumption

Question 28

when does Po2 decrease?

Answer 28

w increasing altitude

Question 29

when altitude changes, what changes and what stays the same?

Answer 29

the proportion of the pressures stays the same but the total pressure decreases

Question 30

what is ventilation rate? how does it affect alveolar Po2?

Answer 30

the amount of air being moved in and out of the lungs per unit time; an increase in ventilation rate will increase alveolar Po2

Question 31

when does increased O2 consumption occur? how does it affect Po2?

Answer 31

increased metabolic activity (like exercise); cells utilize more O2, so it will decrease Po2

Question 32

of the factors that affect partial pressures, which one least affects Pco2?

Answer 32

altitude

Question 33

increased ventilation rate will have what effect on Pco2?

Answer 33

decrease Pco2

Question 34

how will increased O2 consumption effect Pco2?

Answer 34

increase Pco2