Question

Approximately seventy percent of carbon­ dioxide absorbed by the blood will be transported to the lungs

• A. in the form of dissolved gas molecules
• B. as bicarbonate ions
• C. as carbamino-haemoglobin
• D. by binding to R.B.C

Answer 1

The correct option is B

as bicarbonate ions

The correct option is B.

Explanation of correct option:

1. Blood plays an important role in transporting O₂ and CO₂.
2. Nearly 7% of CO₂ is carried through plasma in a dissolved state.
3. About 20-25% of CO₂ is transported by RBCs as carbamino-hemoglobin.
4. Majority of CO₂ (approximately 70%) is carried to the lungs as bicarbonate ions (HCO₃^–).

Final answer: Approximately seventy percent of carbon­ dioxide absorbed by the blood will be transported to the lungs as bicarbonate ions.