Which property of water contributes to its role as a solvent in biological systems?

Water's polarity and its ability to form hydrogen bonds are fundamental to its effectiveness as a solvent in biological systems. The structure of water molecules, which have a partial positive charge near the hydrogen atoms and a partial negative charge near the oxygen atom, facilitates the interaction with various solutes.

When ionic compounds, like salts, are dissolved in water, the positive part of water molecules (hydrogens) surrounds and interacts with negatively charged ions, while the negative part (oxygen) interacts with positively charged ions. This interaction helps to break down the ionic bonds in the salt, leading to the dissociation of the ions in solution.

Furthermore, water can also dissolve many polar molecules, as the attractive forces between polar solutes and water molecules allow for the solvation of these molecules. This property is crucial for biological processes, where many substances, including nutrients, metabolites, and waste products, must be transported and reacted in an aqueous environment. Consequently, the polarity and hydrogen bonding capacity of water are vital for its role as a universal solvent, supporting the biochemical reactions necessary for life.