Question

The ultimate energy source of all ecosystems is?

• A. Producers
• B. Organic molecules
• C. Carbohydrate
• D. Solar radiation

Answer 1

Answer: (D)

Solar radiation

The Sun is the major source of energy for organisms and the ecosystems of which they are a part. Producers such as plants, algae, and cyanobacteria use the energy from sunlight to make organic matter from carbon dioxide and water. This establishes the beginning of energy flow through almost all food webs. The continual input of energy, mostly from sunlight, sustains the process of life. Sunlight allows plants, algae and cyanobacteria to use photosynthesis to convert carbon dioxide and water into organic compounds like carbohydrates. This process is the fundamental source of organic material in the biosphere. The overall productivity of an ecosystem is controlled by the total energy available.

So the correct option is 'solar radiation'.