What percentage of CO2 produced by metabolism is converted into bicarbonate ions in the blood?

1. CO2 produced by aerobic metabolism reacts with water to eventually form bicarbonate ions. 2. Only a small amount of CO2 remains dissolved as gas in body fluids. 3. Over 90 percent of CO2 is converted into bicarbonate ions. 4. 'Exactly 100 percent' overstates this, since some CO2 stays dissolved, so it is ruled out. 5. So over 90 percent is correct. _Source: OpenStax Anatomy and Physiology (CC BY 4.0), Ch 26 "Fluid, Electrolyte, and Acid-Base Balance", p.1261 §Bicarbonate_