Question

QUESTION 26   

1. What does the a-vo2 difference at rest normally average?

   	A.	4–5 mL of oxygen per deciliter of blood
   	B.	10–12 mL of oxygen per deciliter of blood
   	C.	20–25 mL of oxygen per deciliter of blood
   	D.	6–8 mL of oxygen per deciliter of blood

Answer 1

Answer:

Option A (4-5 ml of oxygen per deciliter of blood)

Explanation: vO2 is the difference in the oxygen levels reaching the different body tissues and is calculated as the difference between the bloods carried by the arteries to that of the veins. Thus, it is also called as the arterio-venous blood difference.

As we know that the oxygen diffuses from their higher concentration to that of their lower concentration difference. Further, the oxygenated blood is carried till the body tissues by the arteries because the body tissues have a lower partial pressure of the oxygen as compared to that of the different body tissues.

During the resting state of the body, the arteries carry nearly 20 ml/100 ml of the oxygenated blood till the different body parts which in turn gets exchanged with the venous blood in which the total oxygen concnetration is nearly 15 ml/100 ml of the total blood.

Thus, calculating the difference between the two; the total difference between the arterial and the venous blood which is the vO2 is nearly 5 ml/100 ml of the blood.

Upon changing the units; we know that 100 ml = 1 dl

Therefore; in terms of the dl; the vO2 value at rest becomes 4-5 ml of oxygen per deciliter of the blood.