Chapter 8, Problem 7STP

Summary Introduction

Introduction:

The autotrophs or plant receive sunlight or solar energy of the sun. With the help of their photosynthetic apparatus, the plants make food. During photosynthesis, light energy in the form of sunlight is used by plants. The plants produce food and make it available to other organisms. The producers or plants form the base of an ecosystem and supply energy to the next trophic levels which continues in a chain like manner.

Answer to Problem 7STP

Correct answer :

The correct answer is option (C).Light energy into chemical energy.

Explanation of Solution

Explanation/justification for the correct answer:

Option (C) Light energy into chemical energy. Most plants or autotrophs harness the light energy from sun to produce food. The water from the soil with carbon-di-oxide from air is converted into nutrients. The nutrients or chemicals are then serve as food to the other organisms. So, thecorrect answer is option (C).

Explanation for incorrect answer

Option (A)Chemical energy into mechanical energy. The energy of sun is trapped by the plants to make chemicals in form of organic and inorganic compounds. The compounds leave stored chemical energy. Plants are eaten by animals and the chemical energy is converted into mechanical energy to fuel a living, growing and moving body of animals. So, this is an incorrect answer.

Option (B) Electrical energy into thermal energy. The major sources of energy generations are fossil fuels, Nuclear energy and other sources. Thermal power plants convert the electrical energy into thermal energy. So, this is an incorrect answer

Option (D)Mechanical energy into thermal energy.The food eaten by the animals provides energy to carry out different life processes. The food energy gets changed into thermal energy which helps the organisms to maintain body temperatures especially in cold blooded organisms. So, this is an incorrect answer.