Hemoglobin preference?

Question

Hemoglobin, which is the main protein in red blood cells, is responsible for transporting oxygen gas and carbon dixoide throughout the body. However, hemoglobin actually prefers carbon monoxide over both of these gases. When carbon monoxide attaches to the hemoglobin, it literally becomes "stuck" and is not readily released.

Why does hemoglobin prefer carbon monoxide, given that all aerobic organisms breathe in oxygen gas and breathe out carbon dioxide?

Answer 1

It is true that carbon monoxide forms a stable bond to the iron atoms, and is not easily released.  It becomes stuck and is not readily released because the mitochondria can't use it.  

It's just nature's coincidence, such as when a black widow spider bites a human, it's deadly.  But it's venom was never meant to kill a human, unless a spider can eat a whole human =p

Hope this helped.

Answer 2

Because Carbon monoxide forms a stable complex with

the iron atom of hemoglobin, which is supposed to carry oxygen from the

lungs to the tissues.  When carbon monoxide attaches to the iron, however,

the oxygen can't, so the tissues don't get the oxygen they need.

Edit...it is an accident of the "evolution of man", since CO is a Man-Made Gas.