Question

How carbon monoxide, emitted by automobiles, prevents transport of oxygen in the body tissues [CBSE PMT 1998]
A) By chaning oxygen into carbon dioxide
B) By destroying the haemoglobin
C) By forming a stable compound with haemoglobin
D) By obstructing the reaction of oxygen with haemoglobin

Answer 1

By forming a stable compound with haemoglobin
➡️ carbon monoxide, emitted by automobiles, prevents transport of oxygen in the body tissues

Answer 2

Carbon monoxide emitted by automobiles prevent transport of oxygen in body tissues as CO forms stable compound with haemoglobin.

So ans is (c)

●the cabon monoxide taken by us forms stable compound with haemoglobin as carbamino-haemoglobin which is much stable than oxyhemoglobin hence once formed it prevens binding of oxygen .

●RBC has carbonic anhydrase which convert CO in haemoglobin to bicarbonate ions which is trapped at tissue level thus preventing oxygen to bind to body tissues.