Which of the following best describes the overall chemical equation for photosynthesis as depicted in standard AP Biology diagrams?

• A. 6\ \mathrm{CO}_2 + 6\ \mathrm{H}_2\mathrm{O} \rightarrow \mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6\ \mathrm{O}_2
• B. 6\ \mathrm{CO}_2 + 12\ \mathrm{H}_2\mathrm{O} \rightarrow \mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6\ \mathrm{H}_2\mathrm{O} + 6\ \mathrm{O}_2
• C. 6\ \mathrm{O}_2 + \mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 \rightarrow 6\ \mathrm{CO}_2 + 6\ \mathrm{H}_2\mathrm{O}
• D. \mathrm{CO}_2 + \mathrm{O}_2 \rightarrow \mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + \mathrm{H}_2\mathrm{O}

Answer: (A)

Verified step by step guidance

1. Step 1: Begin by understanding the process of photosynthesis. Photosynthesis is the process by which plants, algae, and some bacteria convert light energy into chemical energy stored in glucose. The process primarily occurs in the chloroplasts of plant cells.
2. Step 2: Recall the general chemical equation for photosynthesis. It involves carbon dioxide (CO₂) and water (H₂O) as reactants, and glucose (C₆H₁₂O₆) and oxygen (O₂) as products. The equation also requires light energy and chlorophyll as catalysts.
3. Step 3: Analyze the options provided. The correct equation should balance the number of atoms on both sides of the reaction. For standard AP Biology diagrams, the most commonly accepted equation is: 6 CO₂ + 6 H₂O → C₆H₁₂O₆ + 6 O₂. This represents the net reaction, where water is consumed and oxygen is released.
4. Step 4: Consider alternative representations. Some diagrams may include intermediate steps or additional water molecules, such as 6 CO₂ + 12 H₂O → C₆H₁₂O₆ + 6 H₂O + 6 O₂. This accounts for the water molecules used in the light-dependent reactions and regenerated in the Calvin cycle.
5. Step 5: Eliminate incorrect options. For example, the equation 6 O₂ + C₆H₁₂O₆ → 6 CO₂ + 6 H₂O represents cellular respiration, not photosynthesis. Similarly, CO₂ + O₂ → C₆H₁₂O₆ + H₂O is not balanced and does not accurately describe photosynthesis.