C04 - The Atmosphere and Respiration Flashcards
What is the MSL Temperature?
+15°C.
What is the MSL Pressure (3)?
- 1013.25 hPa.
- 29.92 inHg.
- 760 mmHg.
What is the MSL Density?
1.225km/m³.
What is Dalton’s Law?
The Total Pressure is the sum of all pressures of each gas in the Atmosphere.
What is the formula of Dalton’s Law?
Total Air Pressure = P N2 + P O2 + P CO2 + P others + P H2O.
What is Henry’s Law?
The amount of gas dissolved is proportional to its Partial Pressure.
True or False. As Atmospheric Pressure drops, so too will the Partial Pressure of its constituent gases?
True.
As Altitude ‘____’, the amount of Oxygen absorbed into the blood stream will ‘____’ (2)?
- Increases.
- Decreases.
What is the minimum Partial Pressure of Oxygen in the Lungs required in an Aviation Environment?
55 mmHg.
At what Altitude can the effects of Partial Pressure below 55 mmHg occur?
12,000 ft.
By ‘____’, ‘____’ Oxygen is needed to maintain a Partial Pressure of Oxygen equivalent to that at sea level (2)?
- 33,700 ft.
- 100%.
At ‘____’, no amount of Oxygen (even at 100%) produces the minimum Partial Pressure of 55 mmHg?
40,000 ft.
What requirement of Oxygen is needed up to 10,000 ft?
No specific requirement.
What requirement of Oxygen is needed above 10,000 ft?
Supplemental Oxygen required.
What requirement of Oxygen is needed from 10,000 ft to 33,700 ft?
Increasing percentage of Oxygen required.
What requirement of Oxygen is needed from 33,700 ft to 40,000 ft?
100% Oxygen required.
What requirement of Oxygen is needed above 40,000 ft?
Pressurised 100% Oxygen required.
The Cabin Pressure is allowed to drop progressively to a value equivalent to an Altitude of about ‘____’ and no more than ‘____’ (2)?
- 6,000 ft.
- 8,000 ft.
Flight Crews are required to use supplemental oxygen if Cabin Pressure exceeds ‘____’ for ‘____’, or whenever the Cabin Altitude exceeds ‘____’ for ‘____’ (4)?
- 10,000 ft.
- 30 minutes or more.
- 13,000 ft.
- Any period of time.
What is Boyle’s Law?
The sum of pressure and volume of gas remains constant in an enclosed area.
According to Boyle’s Law, if Pressure increases, the volume must?
Decrease.
According to Boyle’s Law, if Pressure decreases, the volume must?
Increase.
What is Charles’ Law?
The volume of mass of gas is directly proportional to its Temperature at a constant Pressure.
‘____’ is a semi rigid tube about ‘____’ in diameter, held in shape by rings of ‘____’ (3)?
- Trachea.
- 1.8 cm.
- Cartilage.
The Trachea branches into two main ‘____’?
Bronchi.
Define Alveoli?
Small spherical bag-like structures grouped into clusters called Alveolar Sacks.
True or False. The arrangement of Alveoli gives the maximum possible contact between the air in the Alveoli and the blood supply?
True.
There are about ‘____’ Alveoli in an average Lung providing a total area for gas exchange of about ‘____’ (2)?
- 300 million.
- 80m².
Once in the blood plasma, the Oxygen molecules bind to the ‘____’ carried in the red blood cells?
Haemoglobin.
The process of taking Oxygen from the air and diffusing into the blood stream and expelling unwanted gases is called?
External Respiration.
The use of Oxygen within each cell to create energy by oxidising fuel is called?
Internal Respiration.
The maximum lung volume of about ‘____’ is called the ‘____’ (2)?
- 6 Litres.
- Total Lung Capacity.
Not all air in the lungs is breathed out. Approximately ‘____’ remains. This is called the ‘____’ (2)?
- 1.4 Litres.
- Residual Volume.
The volume of air breathed in and out is known as the ‘____’ and averages about ‘____’ during quiet breathing (2)?
- Tidal Volume.
- 500 ml.
The Tidal Volume increases as the demand for Oxygen ‘____’?
Increases.
The ‘____’ is the maximum amount of air that the person can breathe in and then forcibly out?
Vital Capacity.
The difference between the current Tidal Volume and the Vital Volume is the ‘____’?
Reserve Volume.
The difference between the amount of breath actually taken in, versus the amount of air that could be taken in, is called the ‘____’?
Inspiratory Reserve Volume.
The difference between the amount of air actually breathed out, to the amount of air that could possibly breathe out, is called the ‘____’?
Expiratory Reserve Volume.
The average rate of respiration is about ‘____’?
12 breaths per minute.
The saturation level of Oxygen in the blood stream only starts to fall below ‘____’ when the partial pressure drops to 60 mmHg. Above that, Oxygen Saturation is held close to ‘____’ (2)?
- 90%.
- 98%.
Define Hypoxia?
Insufficient Oxygen to support the metabolism of the tissues.
Define Hypoxic Hypoxia?
Insufficient Partial Pressure of Oxygen.
Define Anaemic Hypoxia?
Insufficient amounts of Haemoglobin in the red blood cells.
Define Stagnant Hypoxia?
Result of low/poor blood flow.
Define Histotoxic Hypoxia?
Poisoning of the blood cells resulting in low supply of Oxygen to body cells.
Which Hypoxia is the real risk for Pilots?
Hypoxic Hypoxia.
True or False. A biological cause of Hypoxia is Asthma?
True.
Define Hyperventilation?
Breathing faster and/or deeper than necessary for the body’s current demand of Oxygen.
What happens when Hyperventilating?
Lack of CO2 in the blood caused by excessive flushing of CO2.
Define Humidity?
The amount of Water Vapour in the Atmosphere.
‘____’ Temperatures require more Water Vapour to reach saturation?
Higher.
Lower Temperatures require ‘____’ Water Vapour to reach saturation?
Less.
True or False. As the Temperature of an Air Mass decreases it will eventually reach its saturation point (Dew Point) without adding any more water?
True.
Define Absolute Humidity?
A quantity representing the actual amount of Water Vapour in a Gas.
True or False. Absolute Humidity does take Temperature into consideration?
False. It does not.
True or False. Absolute Humidity doesn’t vary with changes in Air Temperature and Pressure?
False. It does.
Define Relative Humidity?
The amount of Water Vapour present in the air, expressed as a percentage of the amount required to reach saturation at the same Temperature?
A higher percentage means that the air-water mixture is ‘____’?
More Humid.
Relative Humidity is a good indicator of the likelihood of what (3)?
- Precipitation.
- Dew.
- Fog.
Define Specific Humidity?
The ratio of Water Vapour content to the Total Air Content on the mass basis.
Define Mixing Ratio?
The weight of Water Vapour per unit weight of dry air.
What is the difference between Specific Humidity and Mixing Ratio (2)?
- Specific Humidity includes the weight of Water Vapour.
- Mixing Ratio uses the weight of Dry Air.
The Atmosphere is made up of ‘____’ Water Vapour?
1%.
The air in our Lungs remains constantly ‘____’ saturated at ‘____’ (2)?
- 100%.
- 37°C.
Water Vapour in the Lungs reduces the Total Pressure of Air in the Lungs by a constant ‘____’?
47 mmHg.
What is the Total Pressure in the Lungs when at sea level?
713 mmHg (760-47).
