Unit 5 - Breathing PART C Flashcards
Gases move DOWN pressure gradients, from areas of ___ pressure to areas of ___ pressure.
HIGH
LOW
(like BF)
Gas pressures in the air and blood are measured in…
mmHg.
ATMOSPHERIC PRESSURE - BP & environmental air pressure in mmHg
The respiratory system creates changes in gas pressure by…
the contraction and relaxation of skeletal muscles that act to increase and decrease the volume of the thoracic cavity (and by extension the volume and pressure of gasses in the lungs).
So we need to understand the relationship between gas volume and gas pressure, which is given in…
Boyle’s Law
Boyle’s Law:
P1V1 = P2V2
Boyle’s Law: P1V1 = P2V2
for a given quantity of gas in an airtight container, the pressure is inversely related to the volume of the container (as volume decreases, pressure increases, and as volume increases, pressure decreases).
Boyle’s Law: P1V1 = P2V2
For example if P1 = 100mmHg of a gas in a 1.0 liter container, how does the pressure change when that same gas is put into a container of 0.5 liters?
(100 mmHg) (1.0L) = (P2) (0.5 L), so P2 = 100 mmHg/0.5L = 200 mmHg/L, which is a higher pressure. This equation demonstrates that decreasing the volume of a gas , increases the pressure of that gas.
Respiratory air flow is similar to ___ in the CV system b/c…
BF
both air & blood are fluids
What is a primary difference b/t respiratory air flow & BF in the CV system?
blood is a NONcompressible liquid but air is a compressible mixture of gases
In the respiratory system, changes in the volume of the chest cavity during ventilation cause…
pressure gradients that create air flow
When chest volume INCREASES, alveolar pressure ____, & air flows ___ the respiratory system
FALLS
INTO
When chest volume DECREASES, alveolar pressure ____, & air flows ___ into the atmosphere
INCREASES
OUT
The movement of air is _____ b/c the ENTIRE gas mixture is moving rather than merely 1 or 2 of the gases in the air
BULK FLOW
The air we breathe is ______, which is composed not only of oxygen, but also nitrogen, carbon dioxide, and trace amounts of other gases like carbon monoxide.
atmospheric air
The air we breathe is atmospheric air, which is composed…
not only of oxygen, but also nitrogen, carbon dioxide, and trace amounts of other gases like carbon monoxide.
When we examine the oxygen and carbon dioxide pressures involved in respiration, we must account for this mixture using…
Dalton’s Law
Dalton’s Law:
Total pressure of a mixture of gases = the sum of the partial pressures (P) that each gas exerts independently. In air with high humidity, this also includes the partial pressure of the water vapor.
The pressure of atmospheric air at sea level is ______. Changes in altitude produce changes in…
760 mmHg
total atmospheric air pressure pressure, as do changes in humidity.
