Transport of CO2

Question 1

The 3 ways CO2 is transported

Answer 1

(1) Disolved in plasma (5%)
(2) Associated w/ HB to form carbohinahaemoglobin (10%)
(3) Transported as hydrogen carbonate ions - HCO3 (85%)

Question 2

How (2) works

Answer 2

CO2 + HB => carbominohaemoglobin

Question 3

How (3) works

Answer 3

CO2 + H2O => H2CO3 (carbonic acid)

Product broken down by the enzyme carbolyxanhydrase into H ions
: bonds w/ HB =>HHB (acts as buffer) => w/ Cl- => HbO2 that releases O2

HCO3 diffuses out of RBC

Question 4

The Bohr Effect

Answer 4

In a CO2 rich environment like respiring tissue, more oxygen dissociates from oxyhaemoglobin

Oxygen dissociation curve shifts to the right - requires higher CO2 to saturate HB due to H+ compettition