Indicate the flow of energy in an ecosys | Class 10 Science Chapter Our Environment, Our Environment NCERT Solutions

Current NCERT chapter

Academic session 2026-27, Chapter 13 in the current curriculum.

Welcome to the NCERT Solutions for Class 10 Science - Chapter Our Environment. This page offers a step-by-step solution to the specific question from Exercise 0, Question 31:

Indicate the flow of energy in an ecosystem. Why is it unidirectional? Justify.

. With detailed answers and explanations for each chapter, students can strengthen their understanding and prepare confidently for exams. Ideal for CBSE and other board students, this resource will simplify your study experience.

Question 31:

Indicate the flow of energy in an ecosystem. Why is it unidirectional? Justify.

Answer:

An ecosystem does not have its own source of energy so they receive the energy from the sun. Total incoming solar radiations trapped by the producers (green plants) and change this energy into the chemical energy in the synthesis of food. When the green plants are eaten by the herbivores with the efficiency of energy capture 1% of sunlight, a lot of energy is lost as heat or consumed in the metabolic reactions for their growth and the rest is used for the development or reproduction. When the primary consumers are the herbivores 10% (10% law) of the amount of energy of herbivores is transferred to the primary consumers level and the same process repeats for the next trophic level with the sharing of 10% energy from the previous level. There can be only 4-5 trophic levels. Thus when the energy is transferred at each level, less amount of usable energy is available for the last trophic level. Flow of energy is always unidirectional and shows an upright pyramid.

                                          

Flow of energy is unidirectional because energy captured by the producers or the green plants does not revert back to the solar input but it passes to the herbivores for their metabolic reactions. And, when the energy is passed to the herbivores it does not go back to the producers but passes to the primary consumers or the carnivores. At each trophic level there would be a progressive decrease in the energy due to the energy being lost as heat in respiration, development and reproduction.


Study Tips for Answering NCERT Questions:

NCERT questions are designed to test your understanding of the concepts and theories discussed in the chapter. Here are some tips to help you answer NCERT questions effectively:

  • Read the question carefully and focus on the core concept being asked.
  • Reference examples and data from the chapter when answering questions about Our Environment.
  • Review previous year question papers to get an idea of how such questions may be framed in exams.
  • Practice answering questions within the time limit to improve your speed and accuracy.
  • Discuss your answers with your teachers or peers to get feedback and improve your understanding.

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Welcome to the NCERT Solutions for Class 10 Science - Chapter . This page offers a step-by-step solution to the specific question from Excercise 0 , Question 31: Indicate the flow of energy in an ecosystem. Why is it unidirectional? Justify.....

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