Chapter 2, Problem 9STP

Summary Introduction

Introduction : Ecologists use food chains and food webs to study the flow of energy through an ecosystem. Food chains and food webs represent flow of energy through various trophic levels. Organisms at each trophic level get their energy from the trophic level below it.

Answer to Problem 9STP

Correct answer :

The correct answer is option B. It moves into the surrounding environment.

Explanation of Solution

Explanation for incorrect answer:

The energy that the fox uses for maintaining its body temperature moves into the surrounding environment. The fox gets its energy from the mice, rabbits, squirrels and birds. It uses a part of this energy to carry out its cellular activities. Rest of the energy is used to maintain its body temperature and is lost as heat. It is released into the environment and is no longer available to other organisms.

Explanation for incorrect answer:

Option A. It is taken up by decomposers that consume the fox- When the decomposers consume the foxes; they use up the energy that is available in fox as animal meat. A lot of energy is also lost to the environment. This energy is not available to decomposers. Hence, this is not a correct option.

Option C. It stays in the fox through the metabolism of food- The fox gets its energy from the mice, rabbits, squirrels and birds. It uses a part of this energy to carry out its cellular activities. Rest of the energy is used to maintain its body temperature and is lost as heat. Hence, this is an incorrect option.

Option D. It travels to the next trophic level when the fox is eaten- The energy that is lost as heat is not available to organisms in the next trophic level. Hence, this option is incorrect.