Question

what is the role of water in most biological molecules?

water dissolves molecules and helps reactions occur

water forms the backbone of dna

water acts as an enzyme

water is never involved in chemical reactions

Explanation:

• Analyze each option:
• Option 1: Water is a universal solvent in biological systems, dissolving many polar and ionic molecules. It also provides a medium for biochemical reactions (like hydrolysis, dehydration synthesis) to occur.
• Option 2: The backbone of DNA is made of sugar - phosphate groups, not water.
• Option 3: Enzymes are proteins (or RNA in some cases) that catalyze reactions; water does not act as an enzyme.
• Option 4: Water is involved in many chemical reactions, e.g., photosynthesis, cellular respiration, and hydrolysis reactions.

Answer:

A. Water dissolves molecules and helps reactions occur