Gas exchange Flashcards
what is pressure?
force exerted per unit area. Gas exerts uniform pressure on all surfaces
how do gases exert pressure
- ) number of molecules that impact container
2. ) strength of impacts (Kinetic energy from temperature)
Ideal gas law
PV=nRT partial pressure (volume)= (amount of gas)(gas constant 0.082) (temp in kelvin)
boyles law
P1V1=P2V2 P∝1/V
at constant temp. pressure of gas is inversely proportional to the volume of gas
charles law
V1/T1=V2/T2 V∝T
at constant pressure volume of gas is proportional to temp. of gas
Gay boy lussacs law
P1/T1=P2/T2 P∝T
partial pressures of gas
N=79% O=21% CO2=.04% (.0004) (to find partial pressures just multiply by atmospheric pressure, but when air is humidified you must subtract partial pressure of h20 first )
henry’s law
[gas]=(PPgas)(solubility coefficient)
solubility coefficient is how easy it is for gas to dissolve in solution.
actual/ relative solubility of O2
.024/1
actual/ relative solubility of CO2
.57/24
actual/ relative solubility of N
.01/.5
actual/ relative solubility of He
.008/.33
diffusabilty
diffusion∝ ((delta P)(Area)(solubility))/((distance)(sqrt molecular weight))
surface area and distance constant for all gases. assuming the same pressure for all gases formula turns into :diffusion∝(solubility)/(sqrt (molecular weight))
movement of gas proportional
delta P, surface area, gas solubility,
movement of gas inversely proportional
distance, gas molecular weight
saturation
percentage of heme molecules bound with O2
oxyhemoglobin vs. deoxyhemoglobin
affinity
how easy it is for heme molecules to bind or release O2
high affinity: easy to bind hard to release
low affinity: hard to bind, easy to release
bohr effect
changes in [CO2] affects affinity for O2. increased CO2 decreases O2 affinity