Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

S2 MAP II > Gas Exchange and Gas Transport > Flashcards

Gas Exchange and Gas Transport Flashcards

1
Q

what is emphysema

-leading cause

A

form of COPD
deterioration of the alveoli - less surface area
smoking is leading cause

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

diffusion

-what is it

A

process of randomly moving molecules making their way back and forth across the respiratory membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

diffusion requires…

A

motion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

total pressure at sea level

-composition

A 
760 mmHg
nitrogen: 78.62%
oxygen: 20.84%
CO2: 0.04%
water: 0.50%
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

nitrogen partial pressure

A

600 mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

oxygen partial pressure

A

160 mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

partial pressure of a gas in fluid is determined by

A

concentration

solubility coefficient of the gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

partial pressure in fluid

-equation

A

concentration of dissolved gas / solubility coefficient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

solubility coefficient of O2 and CO2

A

O2
-0.024
CO2
-0.57

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

net rate of diffusion determined by…

A 
pressure difference
solubility of the gas in the fluid
cross-sectional area of the fluid
distance gas must diffuse
molecular weight of the gas
temperature of the fluid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

diffusion is proportional to…

A 
(delta P x A x S) / (d x sqrt MW)
P: pressure
A: cross sectional area
S: solubility
d: diffusion distance
MW: molecular weight
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

diffusion coefficient of

  • oxygen
  • CO2
  • CO
  • nitrogen
  • helium
A 
oxygen
-1
CO2
-20.3
CO
-0.81
nitrogen
-0.53
helium
-0.95
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

respiratory gases

  • very soluble in…
  • -implication
A

very soluble in lipids

-diffusion across membranes occurs relatively easily

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

limiting factor in rate of diffusion of gas through tissue

A

water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

purpose of concentration of O2, CO2, H2O, and N2 in making up pressure in body

A 
O2
-constantly being absorbed from alveoli
CO2
-constantly diffusion from blood into alveoli
H2O
-air is humidified in respiratory tract (water vaporizes)
-PH2O at body temperature = 47 mmHg
N2
-makes up balance to total 760 mmHg
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

change in N2 partial pressure in

  • atmospheric air
  • humidified air
  • alveolar air
  • expired air
A

highest in atmospheric air (597)

decreases in other 3 (similar values; 563.4 - 569)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

change in O2 partial pressure in

  • atmospheric air
  • humidified air
  • alveolar air
  • expired air
A

highest in atmospheric air (159)
decreases to lowest in alveolar air (104)
slightly higher in expired air (120)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

change in CO2 partial pressure in

  • atmospheric air
  • humidified air
  • alveolar air
  • expired air
A

0.3 in atmospheric and humidified air
40 in alveolar air
27 in expired air

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

change in H2O partial pressure in

  • atmospheric air
  • humidified air
  • alveolar air
  • expired air
A

3.7 in atmospheric air

47 in humidified, alveolar, and expired air

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

alveolar air replacement

A

get partial replacement of alveolar air with each breath
new air into alveoli with each breath - 350 ml (same amount of old air expired)
therefore, 1/7 alveolar air replaced by new air each breath

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

alveolar oxygen concentration

  • controlled by
  • PO2 in alveoli cannot exceed _____ at sea level
  • -why?
A

controlled by
-rate of absorption by pulmonary capillaries (amount leaving the alveoli)
-rate of oxygen entry into alveoli via ventilation (amount entering the alveoli
PO2 in alveoli cannot exceed 149 mmHg
-pressures of the other gases limits it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

respiratory membrane

-rapid diffusion of gases aided by what properties of the tissues?

A

large surface area of respiratory membrane with small amount of blood spread throughout
small diameter of pulmonary capillaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

diffusion of gases through respiratory membrane

  • similar to
  • affected by…
A 
similar to diffusion fo gases through water
affected by
-thickness of membrane
-surface area of respiratory membrane
-diffusion coefficient
-pressure difference across the membrane
24
Q

respiratory membrane’s diffusion capacity

-what is it?

A

volume of a gas that will diffuse through the membrane each minute for a partial pressure difference of 1 mmHg

25
normal Va/Q (ventilation perfusion ratio) | -what is it?
0.8
26
what 2 Va/Q values would result in no gas exchange occurring?
zero (no ventilation) | infinity (no perfusion)
27
what 2 factors determine the PO2 and PCO2 in the alveoli
ventilation rate | solubility
28
what is the partial pressure at the arterial end for - O2 - CO2
O2 -40 mmHg CO2 -45 mmHg
29
at rest, where does pulmonary diffusion occur?
in the first 1/3 of the capillary length
30
bronchial arteries | -function
supply deep tissues of lungs and do not come into contact with lung air - returned via pulmonary veins
31
PO2 in - interstitial fluid surrounding tissue cells - tissue cells
interstitial fluid -40 mmHg tissue -5-40 mmHg
32
tissue cells require _____ to fully support chemical processes
1-3 mmHg
33
transport of CO2 from tissues - CO produced when... - rate of CO2 diffusion compared to O2
CO2 produced in cell when O2 used; cellular CO2 pressure rises pattern of diffusion and transport from tissue cell to alveoli follow same reasoning as O2 in opposite direction CO2 diffuses much more rapidly than O2 (higher solubility) -less pressure difference needed to to cause CO2 diffusion than O2 diffusion
34
intracellular and interstitial PCO2
intracellular -46 mmHg interstitial -45 mmHg
35
affect of blood flow and metabolism on PCO2
decrease in blood flow at tissue interstitial fluid increases PCO2 in the fluid increase in blood flow at tissue interstitial fluid decreases PCO2 in fluid increase in metabolism increases interstitial fluid PCO2 at all blood flow levels
36
hemoglobin - transports _____ % of O2 from lungs to tissues - -_____ carries the rest
97% | rest carried in H2O of plasma and RBCs
37
oxygen-hemoglobin dissociation curve - illustrates... - PO2 has direct effect on _____ - percent saturation of Hgb demonstrated by...
illustrates % of hemoglobin saturated by oxygen at any given point along transport route PO2 has direct effect on O2 binding capacity percent saturation of Hgb demonstrated by oxy-hemoglobin curve
38
oxygen saturation of hemoglobin - PO2 when leaving lungs - -hemoglobin saturation at this point - PO2 at end of tissues - -hemoglobin saturation at this point
``` PO2 lungs -95 mmHg -Hgb = 97% PO2 end of tissues -40 mmHg -Hgb saturation = 75% ```
39
15 grams of Hgb can carry _____ O2 in 100 mg blood (assuming 100% saturation)
20 ml
40
at rest, how much O2 is left at the tissues per 100 ml blood?
5 ml
41
oxygen release from hemoglobin under strenuous exercise conditions
increased O2 use with exercise interstitial fluid PO2 can drop from 40 mmHg to 15 mmHg result: 4.4 ml O2 left in 100 ml blood - net delivery of 15 mL to the tissues combine with increased CO by 6-7x normal, can get 20-fold increase of O2 delivery to tissues
42
factors that shift the curve to the right
increase in blood acidity (lower pH) increase CO2 increased blood temperature increased 2,3-biphosphoglycerate (BPG)
43
factors that shift the curve to the left
higher pH
44
increase in H+ and CO2...
increase in H+ and CO2 shifts curve to right which enhances - release of O2 from Hgb in tissues - oxygenation of blood in lungs
45
Bohr effect - what is it? - purpose
weakening of hemoglobin-oxygen bond | O2 unloaded where it is most needed
46
curve shifts right during exercise due to...
increased CO2 produced increased H+ in muscle capillary blood increased temperature of blood
47
normally, PO2 of _____ is sufficient for cellular reactions
> 1 mmHg
48
_____ is the limiting factor for reactions in the cellq
[ADP]
49
carbon monoxide poisoning
CO combines with Hgb in same location at O2 PCO of 0.4 mmHg allows CO to compete with O2 in combining with Hgb; allows 1/2 of Hgb to bind with CO PCO of 0.6 mmHg can be lethal hyperbaric chamber can displace CO with O2 on Hgb
50
under normal conditions, how much CO2 is transported per 100 mL blood from the tissues to the lungs
4 mL
51
how can CO2 be transported from the tissues to the lungs
CO2 in plasma (7%) combines with H2o to form carbonic acid in the RBC carbonic acid dissociated into H+ and HCO3- -H+ combines with Hgb - "buffered" -HCO3 diffuses out of RBC into plasma (70% of CO2 transport), Cl- diffuses into RBC CO2-Hgb
52
carbon dioxide dissociation curve
normal [CO2] in blood (i.e. volumes percent) is 50 volumes percent (50 mL CO2 per 100 mL blood) 4 mL exchanged during normal blood transport dissociation curve - normal range of blood PCO2 is 45 mmHg in tissues and 40 mmHg in arterial blood
53
effect of CO2 picked up in the tissues capillaries on pH
can decrease pH from 7.41 to 7.37
54
respiratory quotient - what is it - equation - differs depending on... - approximates..... - precise determination of energy expenditure requires...
ratio of metabolic gas exchange RQ = CO2 produced / O2 consumed differs depending on type of substrate metabolized (carb, fat, protein) approximates the nutrient mixture catabolized for energy during rest and exercise precise determination of energy expenditure requires measuring both respiratory quotient and O2 consumption
55
RER - compares... - R changes boased on...
``` compares the CO2 output to O2 intake R changes based on fuels for body metabolism -carbs: R = 1 -fat: R = 0.7 -mix carb, fats, proteins: R = 0.85 ```

S2 MAP II (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions