Question

In the tissues, high concentrations of carbon dioxide
A. increases the affinity of haemoglobin to both oxygen and hydrogen
B. increases the affinity of haemoglobin to oxygen but decreases its affinity to hydrogen
C. decrease the affnitiy to haemoglobin to oxygen but increases its affinity to hydrogen
D. decrease the affinity of haemoglobin to both oxygen and hydrogen.

Answer 1

Correct Answer - C
Increase in the `CO_(2)` content of the blood decreases the pH of the blood. This decreases the affinity of `O_(2)` with Hb. This is calle Bohr effect and is closely realted to the fact that deoxygented Hb binds hydrgoen ions ore actively than does the Hb. This facililates gaseous exchanges because more` O_(2)` is released in the tissues where the amount of `CO_(2)` is more due to metablic activity. At the same time, more `O_(2)` is taken up by the lungs or gills when the amount of `CO_(2)` is low.