Which of the following reactions occurs during photosynthesis?

• A. Breakdown of glucose into carbon dioxide and water
• B. Conversion of glucose into lactic acid
• C. Oxidation of oxygen to form water
• D. Conversion of carbon dioxide and water into glucose and oxygen

Answer: (D)

Verified step by step guidance

1. Understand the process of photosynthesis: Photosynthesis is a biochemical process in which plants, algae, and some bacteria convert light energy into chemical energy stored in glucose. This process occurs in the chloroplasts of plant cells.
2. Identify the reactants and products of photosynthesis: The reactants are carbon dioxide (CO₂) and water (H₂O), and the products are glucose (C₆H₁₂O₆) and oxygen (O₂). This process requires light energy and chlorophyll.
3. Write the balanced chemical equation for photosynthesis: The general equation is: $6_{}\mathrm{CO}{2}_{}+6_{}H{2}_{}O\to C_{}{6}_{}H{\mathrm{12}}_{}O{6}_{}+6_{}O{2}_{}$
4. Explain the role of light energy: Light energy is absorbed by chlorophyll pigments in the chloroplasts, which drives the conversion of carbon dioxide and water into glucose and oxygen through two main stages: the light-dependent reactions and the Calvin cycle.
5. Clarify why the correct answer is 'Conversion of carbon dioxide and water into glucose and oxygen': This matches the chemical equation and the biological process of photosynthesis, distinguishing it from other options that describe cellular respiration or fermentation processes.