Food chains are generally limited to three or four trophic levels because of the significant loss of energy at each step. With each transfer, less usable energy remains, making it unsustainable for more levels.

On average, only about 10% of the energy from one trophic level is transferred to the next level. Most of the energy is lost as heat, used up in digestion, or expended in other metabolic activities.

Autotrophs, or producers, play a crucial role in capturing solar energy and converting it into chemical energy via photosynthesis. This energy is then made available to other organisms (heterotrophs or consumers) in the ecosystem.

A garden is a simple example of an ecosystem. It consists of biotic components like grasses, trees, flowers (rose, jasmine, sunflower), frogs, insects, and birds, as well as abiotic components like soil, temperature, and light.

A food chain is a series of organisms each dependent on the next as a source of food. It consists of different trophic levels: the first level is occupied by autotrophs or producers, the second by herbivores or primary consumers, ...