VENOUS BLOOD

Question 1

CO2 is transported back into the lung in what three forms?

Answer 1

plasmam(7%)
hemoglobin (23%)*
carbonic acid (70%)*
*erythrocytes (90%)

Question 2

what is the partial pressure of CO2 in venous circulation vs arterial?

Answer 2

45 mmHg

40 mmHg

Question 3

the 23% of CO2 that binds to hemoglobin produces what?

Answer 3

carbaminohemoglobin

Question 4

the 70% of CO2 that is converted in red blood cells to carbonic acid is done by what enzyme?

Answer 4

carbonic anhydrase

converts the carbonic acid to bicarbonate and H+ and is transported out by Cl-/HCO3- antipode protein which is why we see elevated levels of HCO3- and lowered levels of Cl- in the plasma termed the chloride shift

Question 5

drug used to inhibit RBC carbonic anhydrase?

Answer 5

acetazolamide, up to 80 mmHg instead of 45 mmHg

Question 6

O2 is present in venous blood, T/F? what is the partial pressure in venous vs arterial blood? what is the oxygen in venous blood attached too?

Answer 6

true

40 mmHg in venous
95 mmHg in arterial

hemoglobin, so only a fraction of the O2 has been lost in systemic circulation