Ventilation Flashcards
Describe how increased oxidative phosphorylation would alter the partial
pressures of O2 and CO2 at different locations throughout the body
in working muscle tissue, PO2 decrease as it is used up, and PCO2 increase as it is created as byproduct.
in lungs partial pressure of PCO2 would be lower than blood, therefor PCO2 move out with gradient, and PO2 come in for same reason.
How might the body maintain homeostasis by minimizing changes in gas
partial pressures?
change breathing depth and frequency
As exercise intensity increases what changes can we measure in the lab?
Heart rate, resp rate, O2 consumption and CO2 prod,
In what situations might the lungs limit exercise performance?
Usually not the limiting factor but can be in situations like athsma, where airways are too narrow, or if there is a plaque buildup (maybe from smoking, or a reduced surface area for gas transfer, maybe pulmonary edema (fluid in lungs)
Why is the amount of oxygen dissolved in blood important?
because O2’s solubility in water is low, it must be carried by hemoglobin, must also be able to diffuse to reach hemoglobin and drop out of hemoglobin to diffuse to tissue
Why would hemoglobin have less affinity for oxygen as exercise intensity
increases
because as ex intensity increases you want O2 to get dropped off there. This happens with degreases in pH, increase in temp, and increase in PCO2.
What regulates a-vO2 difference? Why is a-vO2 difference at the heart
not the same as the a-vO2 difference in the vessels supplying muscle?
a-VO2 diff = difference between arterial and venous blood O2 content.
Depends on how much O2 tiss’s need. Higher intensity = greater a-VO2 diff.
differs at heart because heart use O2 for itself to pump blood (always pumping), whereas tissues us it during exercise (not always exercise).
what limits aerobic capacity
oxygen supply, because musc tiss is very effective at extracting O2
breath rate not limit either.
its more about getting oxygenated blood to the tiss including cardiac output.
What forms of doping might increase the amount of oxygen carried in
the blood? How would they increase performance?
EPO (erythropoietin) increase the red blood cell production which means there are more oxygen carriers to deliver to tissue to make ATP.
Blood doping allows for more blood volume and therefore more O2 carry capacity as well.
why is O2 needed for aerobic performance?
O2 needed for aerobic glycolysis using citric acid cycle, electron transport chain acting as the final acceptor in the electron transport chain combining to form H2O.
A younger sibling challenges you to a breath
holding contest what strategy might you use to
beat them and why would it work?
You could hyperventilate = blow off excess CO2 slightly lowering your PCO2. CO2 receptors give the strongest urge to breathe, therefore by lowering, you can prolong urge to breath. Downside, you could blow off so much CO2 that you run out of O2 before urge to breath kick in = blackout
How might the regulation of breathing differ in
Vancouver vs at Everest base camp?
At sea level, the air is denser therefore more O2 molecules are inhaled per breath, at altitude, the opposite.
How would eating baking soda alter ventilation in the first few seconds of exercise and the first few minutes?
In the first few seconds, the bicarbonate would neutralize acidity produced and reduce the need to breath, after a few minutes, the respiratory response may be delayed due to the buffering capacity but probably eventually overcome buffer.
Why do CO2 and H+ concentration in the blood
tightly correlate?
When cells produce ATP, CO2 is produced. This combines with H2O to create carbonic acid (H2CO3-) which can dissociate into HCO3- and H+ depending on bodies needs.
They are connected by the bicarbonate buffer because bicarbonate (HCO3-) can accept H+ ions and reduce acidity. You can ingest this as baking soda (NaHCO3).
Draw the relationship between ventilatory
equivalent (VE/VO2) and exercise intensity, label lactate threshold and explain the physiology
ventilatory equivalent is the ratio of breathing to O2 consumed (how much breathing is needed to get certain amount of O2).
as intensity increase, VE/VO2 (vent equiv) increase. At some point, this increases rapidly, this. represents the point where lactate production is faster than lactate clearance, body try breath more to cope.
