Water is essential for biological processes involving catalysis primarily because all biological systems evolved in aqueous environments, making water a fundamental solvent for these reactions. While some processes can occur in different solvents, they tend to be significantly slower due to water's unique properties. Enzymes, which are the main biological catalysts, are complex polymers that require specific folding to function effectively. The folding process is largely driven by the hydrophobic effect, where non-polar regions of the enzyme move inward, and polar regions remain outward. In non-aqueous solutions, enzymes cannot achieve the correct conformation, rendering them ineffective in catalyzing reactions.
