Which of the following is the one component in photosynthesis that is not recycled during the process?

• A. Oxygen (O\(_2\))
• B. Carbon dioxide (CO\(_2\))
• C. Water (H\(_2\)O)
• D. Light energy

Answer: (D)

Verified step by step guidance

1. Understand 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 general equation for photosynthesis is: 6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂.
2. Identify the components involved in photosynthesis: The key components are carbon dioxide (CO₂), water (H₂O), oxygen (O₂), and light energy. CO₂ and H₂O are reactants, while O₂ is a byproduct, and light energy drives the reaction.
3. Determine which components are recycled: CO₂ and H₂O are continuously cycled in ecosystems. For example, CO₂ released during respiration is used by plants in photosynthesis, and water is part of the hydrological cycle. Similarly, O₂ produced during photosynthesis is used in cellular respiration.
4. Analyze the role of light energy: Light energy is not a material substance and cannot be recycled. It is absorbed by chlorophyll and other pigments to drive the photosynthetic reactions, but it is not regenerated or reused in the process.
5. Conclude that light energy is the component that is not recycled: Unlike CO₂, H₂O, and O₂, light energy is a one-time input that powers the process but is not part of a cyclical exchange.