export_resp 34 Flashcards

(59 cards)

1
Q

what causes ventilation/perfusion (V/Q) inequality?

A

gravity

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

V/Q is ___ in higher lung than in lover

A

lower

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

PO2 is ___ in higher lung

A

higher

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

why isn’t PCO2 affected by V/Q inequality?

A

CO2 has a greater solubility

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

when do pulmonary capillaries reach pO2 of 100?

A

~25% of length

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

which part of the lungs does most blood flow through?

A

bottom

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

during exercise it takes ___ time to reach equilibrated PO2 (why?)

A

more, increased blood flow rate

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

hyperventilation

A

dec PCO2, inc PO2

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

normal P02 and PCO2

A

O2- 105mmHg

CO2- 40mmHg

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

hyporventilation

A

dec PO2, inc PCO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

CO2 ___ bronchiols

A

relaxes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

pulmonary edema and affects on O2/CO2

A

fluid in lungs, inc diffusion distance, PO2 dec, PCO2 same (when ventilate to compensate or in sever cases, inc CO2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

pulmonary embolism

A

clots blocking arteries, dec flow to regions, dec PO2, more severe more inc PCO2

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

emphysema

A

walls of alveoli and caps broken down, inc resistance, dec surface area, PO2 dec, PCO2 inc with severity

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

pulmonary fibrosis

A

thickening of alveolar walls, inc diffusion distance, dec ventilation bc can’t expand lung, dec PO2, dec PCO2 with severity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

asthma

A

narrowed airways, high mucus production, dec ventilation, dec surface area, dec PO2, inc PCO2 with severity

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

fick’s law

A
V= D*A*(P1-P2)/T
-A= surface area

-T= thickness

D= solubility coeff

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

how is O2 carried in blood?

A

hemoglobin (4 binding sites/1)

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

resting oxygen consumption

A

250 ml/min

we hold 1L

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

hemoglobin structure

A

2 alpha
2 beta

1 heme in each

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

what is PO2 measuring?

A

O2 disovled in plasma

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

what happens to PO2 in blood?

A

when PO2 alveoli > PO2 blood, diffuses into plasma, binds to Hb, released when PO2 blood > PO2 tissues

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

what % of O2 is released to tissues?

A

25

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what effects Hb saturation curve?

A
dec pH/inc H+ (right)
inc temp (right)

inc PCO2 (right)

inc 2,3DPG (right)

25
what are DPGs?
- produced by RBCs during anaerobic glycolysis | - produced in response to hypoxia
26
how does CO2 exist in blood?
1) dissolved in plasma (10%) 2) globin-bound (30%) 3) bicarbonate (HCO3-) (60%)
27
CO2/HCO3 equation
CO2+H2O H2CO3 HCO3- + H+
28
enzyme used in carbonic acid eq?
carbonic anhydrase
29
pH is ___ in venous blood than arterial 
lower
30
3 peripheral chemoreceptors
1) aortic 2) carotid 3) axons to medulla oblongata
31
what stimulates chemoreceptors?
dec PO2, dec pH, inc PCO2
32
central chemoreceptors
in brain, measure PCO2 change in inerstitial fluid, go to medulla oblongata
33
how does brain pH change?
blood PCO2 > brain ECF PCO2, CO2 into brain and dec brain pH
34
are central receptors sensitive to PO2 or H+?
NO
35
when does ventilation change start (PO2)? what is responsible for this change?
60 mmHG | peripheral receptors
36
what is responsible for ventilation change (PCO2 and H+)
central and peripheral chemoreceptors
37
what drives ventilation inc during exercise?
pH (lactic acid)
38
where do the peripheral chemoreceptors signal to?
medullary inspiratory center
39
pH of blood is ___ in arterial blood vs venous
higher
40
what is the CO2 buffer in cells?
proteins (globin)
41
what is respiratory acidosis? alkalosis?
inc PCO2, inc H+, dec pH dec PCO2, dec H+, inc pH
42
how does respiration compensate for metabolic acidosis? alkalosis?
hypoventilation (inc CO2, H+) | hyperventilation (dec CO2, H+)
43
venous PO2 PCO2 pH
100mmHg 40mmHG 7.4
44
arterial PO2 PCO2 pH
40mmHg 45mmHg 7.36
45
Pre-Botzinger
pacemaker cells of respiratory center (in medulla oblongata)
46
how does the respiratory center control inhale/exhale?
pre-botzinger --> VRG/DRG --> motor neurons -->diaphragm/intercostals   --> contractions
47
pneumotaxic/apneustic center
in pons, send signals to pacemakers
48
types of inputs to pre-botz?
sensory (PO2, pH, PCO2, stretch, irritants), pons, cortex (voluntary)
49
action potentials cause?
inspiration
50
what causes expiration?
stopping of APs (passive)
51
what changes depth of breaths?
frequency of APs in burst
52
how does gas exchange occur?
diffusion down the pressure gradient
53
gas exchange direction at alveoli
- CO2 into alveoli | - O2 into blood
54
gas exchange at cells
- CO2 into blood | - O2 into cells
55
what does partial pressure measure?
gas concentration in blood
56
what is the pressure of CO2 in the air?
neglegible
57
what determines gas concentration?
solubility and partial pressure
58
what is more soluble, O2 or CO2?
CO2 - 24x
59
what do central chemoreceptors sense?
CO2 in brain