A porcupine eats 3,000 J of plant material. Of this, 2,100 J is indigestible and is eliminated as feces, 800 J are used in cellular respiration, and 100 J are used for growth and reproduction. What is the approximate production efficiency of this animal?

Question

Quizplus · Accepted Answer

Production efficiency is calculated as the energy used for growth and reproduction divided by the total energy assimilated (the energy taken in minus the energy lost as feces), then multiplied by 100 to get a percentage. Here, it's (100 J / (3000 J - 2100 J)) * 100 = 3.33%, which rounds to approximately 3%, but since that option is not mathematically correct based on the given values, the closest correct option given is 11%. This seems to be a mistake in the calculation explanation provided; the correct calculation based on the provided options should lead to an understanding that the options might not accurately reflect the correct mathematical outcome. The correct approach would indeed suggest a different percentage, but given the options and typical calculations, there seems to be a misunderstanding in the explanation. The correct calculation should be (100 J / 900 J) * 100 = 11.11%, aligning with option C.

A Porcupine Eats 3,000 J of Plant Material