# What do buffers do and why are they important in biological systems?

$p H = p {K}_{a} + {\log}_{10} \left\{\frac{\left[{A}^{-}\right]}{\left[H A\right]}\right\}$
AS the equation indicates, the $p H$ of a buffered solution remains tolerably close to the $p {K}_{a}$ of the acid. Biological systems are extensively buffered as a means to prevent gross changes in solution $p H$ (look at the actions of digestive fluid, or the $C {O}_{2}$, $H C {O}_{3}^{-}$ buffer in blood.)