Place the events of O_2 exchange between the alveolus and the pulmonary capillar
ID: 95079 • Letter: P
Question
Place the events of O_2 exchange between the alveolus and the pulmonary capillary in order. 1. PO_2 of plasma matches PO_2 of alveolus 2. Movement of fresh air from the atmosphere into the alveolus 3. O_2 diffuses from the alveolus to blood plasma 4. O_2 binds to hemoglobin A. 2, 3, 4, 1 B. 2, 1, 3, 4 C. 2, 4, 3, 1 D. 2, 3, 1, 4 If you had an alveolus with an initial volume of 3 ml of air with a total pressure of 810 mmHg and you decrease the volume of this alveolus to 1.7 ml, what would the new pressure be and how would this affect air flow? Assume you are at sea level. A. 459 mmHg: air flow into the alveolus from the environment B. 760 mmHg: no net movement of air C. 1429 mmHg: air flow into the alveolus from the environment D. 459 mmHg: air flow out of the alveolus to the environment E. 1429 mmHg: air flow out of the alveolus to the environmentExplanation / Answer
14. Answer is A
This is because when the oxygen diffuses into the plasma, it immediately binds to to haemoglobin as it is carried by itand not the blood plasma.In other words, Oxygen is not present in unbound state inside plasma.
15. Answer is C
This is because when volume of air decreases inside the alveolus, it is under higher pressure than the environment.This will allow for the movement of air from the environment to enter the alveolus.
Calculation is ; (8.1/ 1.7)* 810= 1.76 *810 = 1429mmHg
(Please note: normal atmospheric pressure of air is 760mmHg)