In the context of ecosystem production and efficiency, which statement best describes the fate of sunlight energy reaching algae during photosynthesis?

• A. Algae use all incoming sunlight energy for photosynthesis, so conversion efficiency is 100%.
• B. Only a portion of incoming sunlight is captured and converted to chemical energy; the rest is reflected, transmitted, or lost as heat.
• C. Most sunlight energy is converted directly into ATP and stored permanently without being dissipated as heat.
• D. All sunlight energy absorbed by algae is converted into biomass without any losses to respiration.

Answer: (B)

Verified step by step guidance

1. Understand that sunlight energy reaching algae is the initial energy input for photosynthesis, but not all of this energy is converted into chemical energy.
2. Recognize that some sunlight is reflected off the surface of the algae or transmitted through without being absorbed, so it does not contribute to photosynthesis.
3. Acknowledge that even the absorbed sunlight energy is not fully converted into chemical energy; some energy is lost as heat during the process.
4. Know that the conversion efficiency of sunlight to chemical energy in photosynthesis is less than 100%, meaning only a portion of the incoming sunlight is captured and stored as chemical energy.
5. Realize that some of the chemical energy produced is used in cellular respiration by the algae, so not all absorbed energy is stored as biomass.