Question

During oxygen transport the oxyhaemoglobin at the tissue level liberates oxygen to the cells because

• A. $O_2$ concentration is high and $C{O}_2$ is low
• B. $O_2$ concentration is low and $C{O}_2$ is high
• C. $O_2$ tension is low and $C{O}_2$ tension is high
• D. $O_2$ tension is high and $C{O}_2$ tension is low

Answer 1

Answer: (C)

$O_2$ tension is low and $C{O}_2$ tension is high

Most of the oxygen is transported bound to haemoglobin as oxyhemoglobin. The diffusion of gases depends on the partial pressure differences of the gases between two surfaces. In tissues, the partial pressure (tension) of oxygen is low as compared to the oxygenated blood. Hence, in tissues oxygen is liberated from oxyhemoglobin.

So, the correct answer is option C.