Question

Which of these gases are mostly transported by binding to haemoglobin?

• A. Carbon dioxide
• B. Sulphur dioxide
• C. Nitrogen
• D. Oxygen

Answer 1

Answer: (A), (D)

The correct options are
A Carbon dioxide
D Oxygen

Most of the oxygen is transported by binding to haemoglobin, while a little of carbon dioxide is transported by this method. Only 20-25$\%$ of carbon dioxide is transported by binding to haemoglobin, about 70$\%$ of it is transported as carbonate ions and around 3$\%$ by simple diffusion.
Nitrogen and sulphur dioxide are normally not transported by the blood.