(a) What is chloride shift ?

Explanation

During `CO_(2)` transport by venous blood, `CO_(2)` diffuses from the tissue cells into the plamsa and theninto the RBC. Within RBC, `CO_(2)` forms `H_(2)CO_(3)` which reacts with KHb to form HHb and `KHCO_(3)-H_(2)CO_(3)+KHb rarr HHb +KHCO_(3)`
`KHCO_(3)` is alkaline. It dissociates into `K^(+)` and `HCO_(3)^(-)` ions `- KHCO_(3)rarr K^(+)+HCO_(3)^(-)`
At the same time, `NaCl` in plasma dissociates into `Na^(+)` and `K^(+)` ions. `Cl^(-)` ion forms `KCl` with `K^(+)` ion in RBC.
`K^(+)+Cl^(-)rarr KCl`
This entry of `Cl^(-)` ion from plasma to `RBC` to plasma is called chloride shift or Hambuger phenomenon.