Carbon dioxide ( CO ₂ ) diffuses into blood from tissue site and passes to alveolar site in the form of

Step-by-step solution

Blood is the medium of transport of O ₂ and CO ₂ . Nearly 20-25 % of CO ₂ is transported by RBCs as carbaminohaemoglobin whereas 70 % of it is carried as bicarbonate through plasma. About 7 % of CO ₂ is carried in dissolved state through plasma. The largest fraction of CO ₂ is converted to bicarbonate ions ( HCO ₃⁻ ) and transported in plasma. When CO ₂ diffuses into the RBCs, it combines with H ₂ O , forming carbonic acid ( H ₂ CO ₃ ) . H ₂ CO ₃ is unstable and quickly dissociates into hydrogen ions and bicarbonat