The whole process of the red blood cells shifting the chloride into the red blood cells and the bicarbonate out of the cell causes a shift of the oxyhemoglobin and is restored when it gets back to the lungs. The lungs help to maintain this shift if working properly because the red blood cells must exchange oxygen and CO2 which in turn shifts into the tissues in the systemic system catching the chloride ions in its path. The enzyme reaction carbonic anhydrase produces the carbonic acid in the red blood cells and when the level or the cell has too much carbonic acid than it breaks the ions into bicarbonate and hydrogen ions. The reversal can occur for the shift when the red blood cells reaches the lungs and the breakdown of carbonic acid into a water molecule and CO2 gas when a person exhales (Allen, 2011).
Allen, V. (2011) The Chloride Shift. 78 Health Steps Journal-Human Physiology. WordPress.com. Retrieved from: www.78steps.com/human-physiology/the-chloride-shift.html