The structural and functional unit of the environment is known as $......$

Which of the following is included in edaphic factors?

What will happen if all the deers are removed in the given food chain?
Plants $\rightarrow$ Deers $\rightarrow$ Tigers

The flow of organic matter in a food chain is unidirectional.

What will be the amount of energy available to the organisms of the $2^{\text{nd}}$ trophic level of a food chain,if the energy available at the first trophic level is $10,000 \, J$?

$(a)$ What is an ecosystem? List its two main components.
$(b)$ We do not clean ponds or lakes,but an aquarium needs to be cleaned regularly. Explain.