Well, basically, when carbon monoxide binds onto the heme group of hemoglobin, it makes the other empty heme groups much more likely to actually bind oxygen molecules. So, by binding to our hemoglobin, carbon monoxide makes or increases the affinity of hemoglobin to oxygen. And that's exactly what creates this leftward shift in the first place. So, due to the higher affinity of carboxy hemoglobin to oxygen, it will make it much less likely that the hemoglobin will actually release the oxygen to the tissues and cells that are exercising in our body. Therefore, even though we'll have plenty of oxygen present in the atmosphere and inside our blood plasma, because carboxy hemoglobin binds oxygen so much more strongly than in the normal case, much less of the oxygen will actually arrive at the tissues of our body. And this condition that can ultimately lead to suffocation is known as carbon monoxide poisoning.