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Flashcards in chapter 23 part 2 Deck (60)
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1

ventilation
-definition
-atmospheric pressure

air will flow from high pressure areas to low pressure areas
-760 mmHg

2

before inspiration: interpleural pressure
-always negative or positive
-what does this do
-___mmHg

-negative
-keeps lungs open
-759 mmHg (-1 mmHg)

3

Before inspiration: interpulmonary pressure

760 mmHg

4

Inspiration
-chest width
-chest depth
-chest vol
-according to boyle law
-interpleural pressure
-air pressure is ___ than outside than in so air flows __

-increase
-increase
-increase
-increase in vol = decrease in pressure
-759 mmHg (-1 mmHg)
-higher; in

5

end inspiration

air pressure inside = air pressure outside

6

expiration
-chest width
-chest depth
-chest vol
-according to boyles law
-intrapulmonary pressure
-air pressure is ___ inside than out, so air will flow __

-decrease
-decrease
-decrease
-decrease in vol = increase in pressure
-761 mmHg (+1 mmHg)
-higher, out

7

gas exchange
-where does it occur
-what is it due to

occurs across the respiratory membrane and across capillary walls between blood and other tissues
-due to pressure gradients

8

dalton's law of partial pressure
-total pressure of a gas mixture is...
-partial pressure
-atmospheric pressure

-the sum of the pressures exerted by each gas
-pressure exerted by a single gas in a mixture
- pN2 + pO2 + pCO2 + pH2O = P

9

formula for partial pressure

Partial pressure of gas A = total atmospheric pressure due to all gases X % of atmospheric pressure composed of gas A

10

Room air
-pO2
-pCO2

-160 mmHg
-0.3 mmHg

11

gas exchange between alveolus and alveolar capillary
-pO2 = 40; pCO2 = 45
-pO2 = 100; pCO2 = 40; alveolar air contains more ___
-pO2 = 100; pCO2 = 40

-deoxygenated blood coming from pulmonary circuit
-incoming air mixes with air remaining in the lungs after last breath; contains more CO2 and less O2 room air
-oxygenated blood goes to left side of the heart and systemic circuit

12

when does blood equalibrate with alveolar air

when pO2 = 100 and pCO2 = 40

13

interstitial fluid and systemic capillary
-pO2 = 95; pCO2 = 40
-pO2 = 40; pCO2 = 45
-pO2 = 40; pCO2 = 45

-systemic capillary carrying oxygenated blood
-cells consumes O2 and produce CO2 (increase in CO2 and decrease in O2 in tissues)
-deoxygenated blood in systemic capillary

14

when does blood equalibrate with the tissues

pO2 = 40 and pCO2 = 45

15

5 principles affecting the efficiency of gas exchange

1. differences in partial pressure across the respiratory membrane are substantial
2. distances involved are short (~0.5 um)
3. Gases are lipid soluable
4. total surface area is large
5. blood flow and airflow are coordinated

16

greater the distance=

the faster the rate of gas exchange

17

what can easily diffuse across plasma membrane

gases because they are lipid soluable

18

large surface area =

more efficient gas exchange

19

what do blood flow and airflow play a role in

maximizing efficiency of both pulmonary ventilation and pulmonary circulation

20

oxygen
-100 ml of blood contains ___ ml of O2; %
-___ is dissolved in plasma
-___ are bound to hemoglobin

-20; 20%
-~1.5%
-~98.5%

21

hemoglobin saturation
-definition
-formula
-what will determine the direction of the reaction

-% of heme units containing bound to O2
-Hb+O2 ->

22

hemoglobin
-pO2 = 100 mmHg
-pO2 = 70 mmHg
-pO2 = 40 mmHg
-pO2 = 20 mmHg
-pO2 = 10 mmHg
-pO2 = 0 mmHg

-99%
-98%
-75%
-35%
-10%
-0%

23

the oxygen-hemoglobin saturation curve
-definition
-___% of Hb is
-___% represents
-is all O2 released in tissues; what does this generate
-change in pO2 produces

graph that relates the saturation of Hb to pO2
-75%, oxyhemoglobin in the tissues
-25%; O2 that has been released in tissues
-no; a reserve of O2
-large changes in amount of O2 released from Hb

24

hemoglobin undergoes what
-what does this promote

a change in shape each time it binds an O2
-the binding of additional O2

25

3 factors that shift O2 + Hb saturation curve to the right
-what does this allow

1. decrease in blood pH (more acidic)
2. Increase in pO2
3. Increase in temp
-allows Hb to release O2 more rapidly (makes it easier to unload O2)

26

Carbon dioxide
-where does it come from
-3 fates

-generated by cellular metabolism
-1. ~70% is converted to a molecule of carbonic acid
2. ~23% bound to the protein portion of Hb molecules
3. ~7% dissolved in blood plasma

27

carbonic anhydrase in RBC
- formula

CO2 + H2O (H2CO3) H+ + HCO3-

28

most of the CO2 is transported as

bicarbonate ions (HCO3-)

29

Respiration
-definition
-cellular rates of absorption =

-restoration of equilibrium
-capillary rates of delivery and removal

30

respiratory centers in the brain
-2

-voluntary and involuntary
-1. medulla oblongata
2. pons