Question

The reaction of $O_2$ and $CO$ with haemoglobin gives:

• A. Only oxygen-haeme complex
• B. Only $CO-$ haeme complex
• C. Both but oxygen-haeme-complex is more stable
• D. Both but $CO-$ haeme-complex is more stable

Answer 1

The correct option is B Only $CO-$ haeme complex

When carbon monoxide binds to hemoglobin, it shifts the entire oxygen-hemoglobin curve not only to the left but also down. The leftward shift takes place because when carbon monoxide binds to the hemoglobin, it makes the other unoccupied heme groups much more likely to bind to oxygen (increases its affinity).

Hence B is correct answer