The Atmosphere, O2 & Respiration - Chapter 4

Question 1

Boyle’s Law

Answer 1

Pressure is inversely proportional to volume

Question 2

Charles’s Law

Answer 2

Temperature is proportional to volume

Question 3

Gay-Lussac’s Law

Answer 3

Temperature is proportional to pressure

Question 4

Dalton’s Law

Answer 4

The sum of the partial pressures gives the total pressure:

P(total) = P(1) + P(2) + P(3) +….P(n)

Associated with hypoxia

Question 5

Henry’s Law

Answer 5

Amount of gas dissolved in a liquid is proportional to the pressure exerted on it.

Associated with decompression sickness

Question 6

Fick’s Law

Answer 6

Law of diffusion (Transfer of gas between cells)

Associated with respiration

Question 7

What are alveoli?

Answer 7

Little sacks of air where diffusion takes place within the lungs

Question 8

What does Hemoglobin do?

Answer 8

Carries O2 around the body with red blood cells.

It’s a type of protein found within blood.

Formed in bone marrow.

Can hold about 55 mmHg before over-saturation occurs. This is the minimum limit in aviation (as a partial pressure).

Question 9

Saturation levels:

Answer 9

MSL = 97.5%
10,000 ft = 87%
20,000ft = 65%

Question 10

Different O2 requirements onboard A/C:

Answer 10

<10,000ft = normal air

10,000 - 33,700ft = O2 & air mix (wear a mask). Body feels at ground level.

33,700 - 40,000ft = 100% O2. Body feels at 10,000ft

> 40,000ft = 100% O2 under pressure. Body feels at 10,000ft.

Question 11

A pressurised cabin is always set to:

Answer 11

6,000 - 8,000 ft

Question 12

Saturation of hemoglobin __________ as altitude ___________.

Answer 12

Decreases as altitude increases

Question 13

Pressure ISA conditions (mmHg)

Answer 13

MSL = 760 mmHg
8,000 ft = 543 mmHg
18,000 ft = 380 mmHg
36,000 ft = 187 mmHg

Question 14

External Respiration =

Answer 14

Outside the lungs

Question 15

Internal respiration =

Answer 15

Within the lungs

Question 16

CO2 & H2O combine to form:

Answer 16

Carbonic acid (a waste product of respiration)

Question 17

Total lung capacity =

Answer 17

6000 ml

Question 18

Tidal volume =

Answer 18

Amount of air inhaled/exhaled in one usual breath (500ml)

Question 19

Inspiratory reserve volume =

Answer 19

Amount of air which can be forcibly inhaled in one breathe (3100ml)

Question 20

Expiratory reserve volume =

Answer 20

Amount of air which can be forcibly exhaled after a tidal exhale (1,200ml)

Question 21

Residual volume =

Answer 21

Amount of air which always remains in the lungs (1,200ml)

Question 22

Vital capacity =

Answer 22

Total of inspiratory reserve volume, tidal volume and expiratory reserve volume (4,800 ml)

Question 23

Inspiratory capacity =

Answer 23

Total of inspiratory volume as well as tidal volume (3,600ml)

Question 24

Functional residual capacity =

Answer 24

Amount of air remaining in the lungs after a normal exhale (expiratory reserve volume + residual volume) (2,400ml)