Gas Exchange & Transport Flashcards
Where does the gas exchange happen?
Alveoli in the lungs!!
Increased thickness= _________ diffusion!!!
DECREASED.
The thicker the membrane the ________ it is for gas exchange to take place!
HARDER.
What could cause the respiratory membrane to thicken?
Pulmonary EDEMA and fluid.
Do the gases move in ONE direction through the respiratory membrane?
NO. They move in BOTH.
What does the two way exchange of gases do?
Converts deoxygenated blood to OXYGENATED blood
Things move from _____ to _____ concentration !!!
HIGH to LOW
What are the four factors that the amount of O2 diffused depends on??
1- Alevolar pressure gradient (higher/lower pressure)
2- The total functional surface of the resp. membrane (how thin it is)
3. The respiratory minute volume
4. Alveolar Ventilation
What are the four factors that the amount of O2 diffused depends on??
1- Alevolar pressure gradient (higher/lower pressure)
2- The total functional surface of the resp. membrane (how thin it is)
3. The respiratory minute volume
4. Alveolar Ventilation
How do we calculate the respiratory minute volume?
RR/min X volume of air inspired
General Rule:
Anything that ______ the alveolar PCO2 tends to _____ the alveolar blood oxygen pressure gradient which results in a _______ amount of O2 entering the blood
DECREASE, DECREASE, DECREASE
What is application 1 of the general rule?
O2 pressure gradient, alveolar PO2 decreases as altitude increases, thus less O2 enters the blood at high altitudes
What is application 2 of the general rule?
Functional surface area, anything that decreases the functional surface area of the respiratory membrane tends to decrease oxygen diffusion into the blood
What is application 3 of the general rule?
Respiratory minute volume, anything that decreases RR tends to decrease blood oxygenation
Blood transports O2 and CO2 either as _______ or _______ with other chemicals.
SOLUTES or COMBINED
When entering the blood, both O2 and CO2 dissolve in the _______
plasma
What is hemoglobin?
reddish protein found in red blood cells
What does O2 have an affinity for?
Iron atoms
- allowing the iron to act as a oxygen sponge that chemically absorbs O2 molecules from the surrounding solution
What does CO2 have an affinity for?
Alpha and beta amino acid chains, allowing HB to sponge to the CO2 and carry it as well
When hemoglobin combines with O2, what does it form?
Oxyhemoglobin
Each gram of HB can unite with ____ml of O2.
1.34ml
The exact amount of _____ in the blood depends largely on the amount of ________ present.
O2 & HEMOGLOBIN
The higher the hemoglobin % naturally higher what?
O2 carrying capacity of the blood is.
What does PO2 stand for?
Partial pressure of oxygen (reflects the amount of oxygen gas dissolved in the blood)
The HIGHER the PO2 in the blood….. what happens to the rate of O2 being bound to HB? (accelerate or deacclerate?)
It ACCELERATES the rate of O2 being bound
The LOWER the PO2 in the blood….. what happens to the rate of O2 being bound to HB?
LOWERS the rate O2 is being bound
What does the O2 dissociation curve represent?
it describes the relationship between the PO2 (x axis) and the O2 saturation ( y axis)
As more O2 binds, the HB O2 affinity INCREASES. True or false?
TRUE!!
What does affinity mean?
the degree to which a substance tends to combine with another
When there is a shift to the RIGHT, HB has a __________ affinity for O2.
DECREASED, does NOT want it.
Which way does the curve shift when it is easier for the HB to RELEASE the O2 molecules?
RIGHT!!!
The curve usually shifts to the right during the times that O2 is needed the _________ !!
MOST
When are some examples of when our body needs O2 the most? (also think of the pneumonic CADET)
Exercise, stress, shock
Co2 Acid Dpg Excerise Temp
When we are hypoxic, is more or less O2 released into the tissues?
MORE O2
When the curve shifts LEFT, HB has an _________ affinity for O2.
INCREASED
What are some reasons the curve will shift left?
carbon monoxide poisoning
hypothermia
cancers of the head and neck
smoking and alcohol
Where are carbomino compounds secreted?
in water or kidneys
What is the majority form of CO2 in the blood carried as?
bicarbonate ions (HCO3-)
The more CO2 that is present = _______ levels of carbonic acid !!
HIGHER
What will happen to the SPO2 of our CARBON MONOXIDE poisoning patients?
Would be NORMAL or HIGH because CO replaces oxygen
Does CO have a greater affinity to HB then O2 does?
YES. 250x greater affinity.
The Bohr effect means:
________ PCO2 >
__________ the affinity between HB & O2 >
causes a ________ shift on the O2HB curve !!
increased
decreases
RIGHT
The Haldane effect is when the O2 in the blood displaces CO2 from the HB and increases the removal of CO2. True or false??
TRUE!!!!!!!
Haldene effect: Oxygenated blood as a reduced affinity for _______ this this effect focuses on the hemoglobins ability to carry INCREASED amounts of ________ in deoxygenated states.
CO2
