Question

The green plants in a terrestrial ecosystem capture about _______ of the energy of sunlight.
1. 4%
2. 2%
3. 1%
4. 3%

Answer 1

Correct Answer - Option 3 : 1%

The correct answer is 1%.

• The green plants in a terrestrial ecosystem capture about 1% of the energy of sunlight that falls on their leaves and converts it into food energy.
• When green plants are eaten by primary consumers, a great deal of energy is lost as heat to the environment, some amount goes into digestion and in doing work and the rest goes towards growth and reproduction. An average of 10% of the food eaten is turned into its own body and made available for the next level of consumers.
• Therefore, 10% can be taken as the average value for the amount of organic matter that is present at each step and reaches the next level of consumers.
• Since so little energy is available for the next level of consumers, food chains generally consist of only three or four steps. The loss of energy at each step is so great that very little usable energy remains after four trophic levels.
• There are generally a greater number of individuals at the lower trophic levels of an ecosystem, the greatest number is of the producers.