Question

The ultimate source of energy for all living organisms is the __ .

Answer 1

Solar energy:

1. Plants make food by the process called photosynthesis.
2. This food is stored in the plants and transferred to the other organism by consuming the plants.
3. Sunlight is essential for photosynthesis.
4. Sunlight provides energy for the reaction between carbon dioxide and water to produce glucose and oxygen.
5. Hence solar energy is considered as the ultimate source of energy.

Final answer:

The ultimate source of energy of all living organisms is

solar energy.