Question

Make a claim identifying how the majority of carbon dioxide is transported in the blood.

a) Dissolved in plasma as bicarbonate ions
b) Bound to hemoglobin in red blood cells
c) Transported as carbon monoxide
d) Stored in lung tissue for exhalation

Answer 1

The majority of carbon dioxide in the blood is transported as bicarbonate ions, converted from carbon dioxide in red blood cells and then transferred into the plasma.

Step-by-step explanation:

Carbon dioxide can be transported through the blood via three methods. It is dissolved directly in the blood, bound to plasma proteins or hemoglobin, or converted into bicarbonate. The majority of carbon dioxide is transported as dissolved in plasma as bicarbonate ions.

The majority of carbon dioxide in the blood is transported as bicarbonate ions. Carbon dioxide can be carried in the blood through three main methods: dissolving directly into the plasma, binding to hemoglobin in red blood cells, or transforming into bicarbonate ions. The most significant method involves carbon dioxide diffusing into red blood cells and with the help of the enzyme carbonic anhydrase, it is converted into carbonic acid (H₂CO₃), which quickly dissociates into bicarbonate (HCO₃⁻) and hydrogen ions (H⁺). The bicarbonate ions are then transferred into the plasma. This bicarbonate system is responsible for transporting the largest amount of carbon dioxide.