Question

Assertion : Human blood always contains more amount of CO$_2$ than blood oxygen.

Reason : Solubility coefficient of CO$_2$ is more than O$_2$.

• A. If both assertion and reason are true and the reason is the correct explanation of the assertion
• B. If both assertion and reason are true but reason is not the correct explanation of the assertion
• C. If assertion is true but reason is false
• D. If both assertion and reason are false

Answer 1

Answer: (B)

If both assertion and reason are true but reason is not the correct explanation of the assertion

Answer 2

The assertion that human blood contains more CO$_2$ than O$_2$ is true, as CO$_2$ content (48-52 mL/100mL blood) is higher than O$_2$ content (15-20 mL/100mL blood). The reason stating that CO$_2$ has a higher solubility coefficient than O$_2$ is also true, with CO$_2$ being about 20-25 times more soluble in plasma than O$_2$.

However, the higher solubility of CO$_2$ primarily explains only the dissolved portion of CO$_2$ transport (7-10%). The majority of CO$_2$ is transported as bicarbonate ions (70%) and carbaminohemoglobin (20-25%). The overall higher amount of CO$_2$ in blood is due to its continuous production as a metabolic waste and these efficient chemical transport mechanisms, not solely its solubility. Thus, the reason does not correctly explain the assertion.