Question

Bulk of carbon dioxide is transported by __________

(a) dissolved state

(b) plasma as bicarbonate

(c) carbamino haemoglobin

(d) methamoglobin

This question was posed to me in an interview for job.

This intriguing question originated from Transport of Gases topic in chapter Breathing and Exchange of Gases of Biology – Class 11

Answer 1

Right answer is (b) plasma as bicarbonate

The explanation: Nearly 70% carbon dioxide is transported by plasma as sodium bicarbonate. Approximately, 5-7% of carbon dioxide is transported in dissolves form in plasma. About 20-25% carbon dioxide react with the amine group of haemoglobin and form carbamino-haemoglobin.