In our body, the blood transports the CO2 in three ways (i) Majority of carbon dioxide produced (70%) in our cells is transported in the form of bicarbonates. In this way first, the CO2 that dissolves in blood plasma reacts with water forming carbonic acid, which dissociates into hydrogen and bicarbonate ions. CO2+H2OCarbonicacidH2CO3H2CO3H++HCO3 (ii) About 7% of all the CO2 of transported by blood from tissues to the lungs is in dissolved state in plasma. (iii) About 23% of CO2 , collected from cells through tissue fluids, is transported by blood in the form of carbamino compound, carbamino -haemoglobin (CO2HHb) .