Which phrase correctly defines net production efficiency? The amount of energy—

• A. stored as biomass after respiration, divided by the total energy assimilated by the organism
• B. captured by chlorophyll during photosynthesis, divided by the total sunlight available
• C. lost as heat during metabolic processes, divided by the total energy assimilated
• D. used for cellular respiration, divided by the total energy consumed

Answer: (A)

Verified step by step guidance

1. Understand the concept of net production efficiency: It refers to the proportion of energy that is stored as biomass after respiration, relative to the total energy assimilated by the organism.
2. Break down the key terms: 'Biomass' refers to the organic material produced by an organism, 'respiration' is the process where energy is used for metabolic activities, and 'assimilated energy' is the total energy taken in by the organism.
3. Eliminate incorrect options: For example, energy captured by chlorophyll during photosynthesis is not directly related to net production efficiency, as this term focuses on energy stored after respiration.
4. Focus on the correct definition: Net production efficiency is calculated as the energy stored as biomass after respiration divided by the total energy assimilated by the organism.
5. Relate the concept to ecological efficiency: This helps in understanding energy flow in ecosystems, where organisms convert assimilated energy into biomass while losing some energy to respiration and heat.