Question

Although much ${\text{CO}}_2$ is carried in blood, yet blood does not become acidic, because:

• A. It is absorbed by the leucocytes
• B. Blood buffers play an important role in ${\text{CO}}_2$ transport
• C. It combines with water to form carbonic acid $\left({\text{H}}_2{\text{CO}}_3\right)$ which is neutralized by $\left({\text{Na}}_2{\text{CO}}_3\right)$
• D. It is continuously diffused through tissues and is not allowed to accumulate

Answer 1

The correct option is B Blood buffers play an important role in ${\text{CO}}_2$ transport

Although much ${\text{CO}}_2$ is carried in the blood, yet blood does not become acidic. It is due to ${\text{CO}}_2$ transport and buffering action of blood. The main buffer present in the blood is bicarbonate. Bicarbonates exist in equilibrium with carbonic acid which in turn can be converted to ${\text{CO}}_2$ and water.
$H_{2}O+C{O}_2\leftrightharpoons H_{2}C{O}_3\leftrightharpoons H^{+}+HC{O}_3^{-}$