chapter 23 part 2 Flashcards Preview

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Flashcards in chapter 23 part 2 Deck (60):
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

31

medulla oblongata
-2 groups

1. dorsal respiratory group (DRG)
2. ventral respiratory group (VRG)

32

dorsal respiratory group
-type of center
-active when

inspiration center
-active every breathing cycle

33

ventral respiratory group
-type of center
-active when

-expiration center
-active only during forced breathing

34

when does alternate inhibition occur

between neurons involved in inhalation and exhalation

35

quiet breathing
-6 steps

1. dorsal respiratory group active (fires action potentials)
2. Inspiratory muscles contract
3. inspiration occurs
4. dorsal respiratory group inhibited
5. inspiratory muscles contract
6. passive expiration occurs

36

forced breathing
-6 steps

1. VRG inhibited; DRG active
2. inspiratory muscles contract and expiratory muscles relax
3. inspiration occurs
4. DRG inhibited; VRG active
5. inspiratory muscles relax and expiratory muscles contract
6. active expiration occurs

37

pons
-2 centers
-function

1. apneustic
2. pneumotaxic
-regulate rate and depth of repiration

38

pneumotaxic center of the pons
-definition
-favors what

inhibits apneustic center
-favors exhalation

39

apneustic center of the pons
-definition

stimulates the DRG
-favors inhalation

40

respiratory rhythmicity centers
-2
-function

-1. DRG
2. VRG
-establish the basic pace and depth of respiration

41

pneumotaxic center modifies that pace:
-increased activity
-decreased activity

- increases pace of respiration by shortening the duration of inhalation
-decreases pace of respiration and increases depth of respiration

42

3 factors that affect breathing

1. carbon dioxide
2. pO2
3. pH

43

carbon dioxide
- 2 factors

-high plasma CO2
-low plasma CO2

44

high plasma CO2
-known as
-cause
-8 steps

-hypercapnia
-hypoventilation
-1. homeostasis disturbed: increased pCO2
2. stimulation of arterial chemoreceptors and increase in pCO2 in CSF
3. increased stimulation of CNS chemoreceptors
4. increased respiratory centers
5. increased respiratory rate and depth
6. increased CO2 elimination in lungs
7. decreased pCO2
8. homeostatsis restored

45

hypercapnia
-definition
-what do you have to do to reverse is

-increase pCO2 of arterial blood
-increase breathing

46

low plasma CO2
-known as
-cause
-8 steps

-hypocapnia
-hyperventilation
-1. homeostasis disturbed: decreased pCO2
2. inhibition of arterial chemoreceptors and decreased pCO2 in CSF
5. decreased stimulation of CNS chemoreceptors
6. decreased respiratory centers
7. decreased rate and depth of respiration
8. decreased CO2 elimination in lungs
9. homeostasis restored

47

hypocapnia
-definition
-what do you need to do to reverse it

-low pCO2 of arterial blood
-decrease breathing

48

factors that affect breathing:
-high or low pO2

low blood oxygen (hypoxia)

49

hypoxia
-function
-must see a ____ before effect is seen

-stimulates chemoreceptors in carotid bodies = respiratory rate and depth
-drop of 40%

50

factors the affect breathing:
- high or low pH

low plasma pH

51

low plasma pH affecting breathing
-increased or decreased concentration of ____
-formula
-decreased pH =
-increased pH =

-increased; hydrogen ion
-CO2 + H2O H+ + HCO3-
- increased pCO2 = increased respiratory rate and depth
-decreased pCO2 = decreased respiratory rate and depth

52

what is the main factor that controls breathing
-a change in pCO2 of ____ is enough to ___

-CO2 concentration in blood
-~10%; double respiratory rate (even is pO2 is normal)

53

7 additional factors affecting rate and depth of repiration

1. higher centers of the brain
2. stretch receptors of the lungs
3. irritant receptors
4. receptors in muscles and joints
5. central chemoreceptors
6. peripheral chemoreceptors
7. other receptors (ex. pain) and emotional stimuli acting through the hypothalamus

54

additional factors affecting rate and depth of respiration: higher centers of the brain
-inhibit or activate respiratory centers
-voluntary or involuntary control over breathing
-ex

-voluntary
-emotions such as anger and fear and singing

55

additional factors affecting rate and depth of respiration: stretch receptors in the lungs
-inhibit or activate respiratory centers
-type of reflex
-function

-inhibit
-hering-breuer reflex
-prevents over expansion and inhibits inspiration

56

additional factors affecting rate and depth of respiration: irritant receptors
-inhibit or activate respiratory centers
-definition
-function

-inhibits
-toxic chemicals or vapors
-increases coughing and sneezing

57

additional factors affecting rate and depth of respiration: receptors in muscles and joints
-inhibit or activate respiratory centers
-defintion

-activate
-anticipation of exercise with increase respiration rate

58

additional factors affecting rate and depth of respiration: central chemoreceptors
-inhibit or activate respiratory centers
-location
-function

-activates
-medulla oblongata
-increase CO2 and increase H+

59

additional factors affecting rate and depth of respiration: peripheral chemoreceptors
-inhibit or activate respiratory centers
-function

-activate
-decrease O2, increase CO2 and increase H+

60

additional factors affecting rate and depth of respiration: other receptors
-inhibit or activate respiratory centers
-function

-both
-increase respiratory rate = fever and chronic pain