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Free Energy in an Aquatic Ecosystem

APBIO-SLAKWS

During colder months, many animals, including fish, enter a state of decreased metabolic activity called torpor. Torpor is characterized by a significant reduction in an animal's metabolic rate, and the graph below illustrates the relationship between oxygen consumption in fish and environmental temperature.

Oxygen Consumption vs. Temperature in a Pond. Gray Mitchell, C. Created for Albert.io. Copyright 2016. All rights reserved.

Which of the following statements provides the BEST explanation for this phenomenon?

A

Fish consume less oxygen during colder temperatures because lowering respiration rate is an adaptation that allows fish to conserve free energy during unfavorable conditions.

B

Fish consume more oxygen during warmer temperatures because their respiration rate slows down, and this adaptation allows them to use more free energy.

C

Fish consume less oxygen during colder temperatures because their respiration increases to compensate for cold weather. This adaptation allows fish to conserve free energy during unfavorable conditions.

D

Fish use less energy during colder temperatures, so their respiration increases as an adaptive response.