1.7 Arterio-venous Oxygen (a-Vo2) difference

Question 1

what is A-Vo2 difference

Answer 1

difference in the vol of oxygen between the arteries and the veins

Question 2

how will the vol of o2 differ between the arteries and the veins

Answer 2

arteries will carry higher vol of o2 than veins

… arteries are carrying o2 in order to supply the muscles with energy

Question 3

during exercise why does the artery-venous o2 difference become higher

Answer 3

• chemo R. detect an increase in co2, causes increased HR
• higher conc gradient at muscles means o2 dissociates from Hb faster = Bohr Shift
• myoglobin rapidly releases o2 allowing aerobic resp.
• result in greater use of o2 in b. stream, so less o2 travels back to the heart in the veins.
• A-Vo2 diff. increased

Question 4

describe A-vo2 diff. in a trained athlete

Answer 4

• increase in Vo2 diff. during Ex.
• can of training a trained athlete is more efficient at transfer o2 between the b. & muscle cells
• … more oxygenated b. is carried from the heart in the arteries to the muscles cells
• greater proportion of o2 is transferred to the muscle cells
• more 02 is used at muscles cells so the vol of o2 present in venous b. is reduced

Question 5

describe A-vo2 diff. in a un-trained athlete

Answer 5

• increase in a Vo2 diff. during Ex. to provide their muscles with 02 during Ex.
• Vo2 diff. smaller than trained athletes
• cas their bodies are not as efficient at transferring o2 from the b. to the muscles cells,
• meaning more o2 is wasted
• limits their performance as their body is not efficient at gases
• muscle fatigue to set in earlier than in trained athletes