Physiology

Question 1

What are surfactants made of?

Answer 1

Apoprotein + phospholipids + Ca+2

Question 2

What produces surfactant in bronchioles?

Answer 2

Clara cells

Question 3

What type of fluid is pleural fluid?

Answer 3

Mucoid (interstitial + protein)

Question 4

What is the main muscle of forceful inspiration?

Answer 4

Sternocleidomastoid

Question 5

What is the main muscle of quiet inspiration?

Answer 5

Diaphragm

Question 6

Muscles of forceful expiration?

Answer 6

Internal intercostals + abdomen

Question 7

How to measure pressure in CMs of water?

Answer 7

mmHg x 1.37

Question 8

What is intrathoracic pressure?

Answer 8

-4

Question 9

When is transmural pressure highest?

Answer 9

End of inspiration

Question 10

What are capacities used for?

Answer 10

Diagnosis restrictive and obstructive diseases

Question 11

How much is tidal volume?

Answer 11

500ml

Question 12

Which volume/capacity can’t be measured by spirometer?

Answer 12

Residual volume and thus FRC

Question 13

How much is inspiratory reserve volume?

Answer 13

3000ml

Question 14

How much is expiratory reserve volume?

Answer 14

1000ml

Question 15

How much is residual volume?

Answer 15

1200ml

Question 16

How much is functional residual capacity?

Answer 16

2200ml

Question 17

How is much is vital capacity?

Answer 17

4500ml

Question 18

How much is total lung capacity?

Answer 18

5700ml

Question 19

What is FEV1?

Answer 19

Forced expiratory volume in 1 second which should be 80% of forced vital capacity

Question 20

What does low FVC indicate?

Answer 20

Restrictive lung disease

Question 21

What does low FEV1 indicate?

Answer 21

Obstructive lung disease

Question 22

Why does exhalation take longer?

Answer 22

Passive + more airway resistance

Question 23

What is dalton’s law?

Answer 23

Total pressure exerted by a mixture equals the sum of all partial pressures

Question 24

Name the 4 factors in fick’s law

Answer 24

1) Membrane thickness
2) Membrane surface area
3) Partial pressure gradient
4) diffusion coefficient of gas
5) Chemical nature of membrane (not applicable here)

Question 25

What is the average thickness of respiratory membrane?

Answer 25

0.6 um

Question 26

Why does CO2 have a higher diffusion coefficient when it’s bigger?

Answer 26

It’s more soluble

Question 27

Rank O2,N2,CO2 in order of diffusion coefficient

Answer 27

CO2>O2>N2

Question 28

What diseases affect respiratory membrane surface area?

Answer 28

Emphysema & elastase production inducers (smoking & cancer)

Question 29

What part of fick’s law could edema affect?

Answer 29

Thickness of membrane

Question 30

What is Henry’s law?

Answer 30

The higher the partial pressure the higher the solubility of a gas

Question 31

CO2 diffuses ….X times more than O2

Answer 31

20

Question 32

How much are PaO2 & PaCO2?

Answer 32

PaO2= 100mmHg PaCO2= 40mmHg

Question 33

How much are PvO2 & PvCO2?

Answer 33

PvO2= 40mmHg PvCO2= 46mmHg

Question 34

Partial pressure of arterial blood in the aorta?

Answer 34

95mmHg

Question 35

What is the diffusion capacity of O2 and CO2 in a resting state?

Answer 35

21 & 420 ml/min/mmHg respectively

Question 36

What is the diffusion capacity of O2 and CO2 during exercise?

Answer 36

65 & 1250 ml/min/mmHg respectively

Question 37

How much does pressure change during breathing?

Answer 37

+- 11mmHg

Question 38

What is the average V/Q ratio in a healthy lung?

Answer 38

0.8

Question 39

What is the average perfusion of the lung?

Answer 39

5.5L/min

Question 40

What is V/Q in upper lobe?

Answer 40

3

Question 41

What is V/Q in the lower lobe?

Answer 41

0.6

Question 42

What are the 2 factors affecting PO2 in tissue?

Answer 42

Blood flow & oxygen consumption

Question 43

How much of oxygen is dissolved in plasma?

Answer 43

1.5-3%

Question 44

What is the concentration of Hb & O2 in saturated blood?

Answer 44

15 grams/dl = 20 ml/dl

Question 45

At what PO2 does O2 saturation plateau?

Answer 45

60 mmHg

Question 46

How much is utilization coefficient?

Answer 46

25-30%

Question 47

What is the effect of temperature on o2 disassociation curve?

Answer 47

Shift to the right

Question 48

What is the effect of BPG on o2 disassociation curve?

Answer 48

Shift to the right

Question 49

At what carbon monoxide partial pressure is Hb saturation almost 100%?

Answer 49

0.6 mmHg

Question 50

What is the percentage of CO2 dissolved in the blood?

Answer 50

7%

Question 51

What is the most common form to transport CO2 in?

Answer 51

HCO3-

Question 52

What is the saturation of Hb with CO2 usually?

Answer 52

50%

Question 53

Where does CO2 bind to in Hb?

Answer 53

Globin amine radicals

Question 54

What is the saturation of Hb by O2 in venous blood?

Answer 54

75%