White House. Washington, D.C. White House, formerly known as the Executive Mansion (1810â1902), the official office and residence of the president of the United States at 1600 Pennsylvania Avenue N.W. in Washington, D.C. The White House and its landscaped grounds occupy 18 acres (7.2 hectares).
Quick Answer. Ecological balance is a theory stipulating that natural conditions, including numbers of various animal and plant species, remain stable on their own through variations over time.
A balanced aquarium is an example of a very small ecosystem. It is self-supporting because the requirements for a stable ecosystem are present: ENERGY (1) is supplied to the ecosystem by light. There are PLANTS (2) to change the light energy into the organic molecule of energy (glucose).RECYCLING (3) of materials occurs during photosynthesis and respiration. During photosynthesis, plants use light energy and carbon dioxide to form glucose. balanced aquarium is an example of a very small ecosystem. It is self-supporting because the requirements for a stable ecosystem are present: ENERGY (1) is supplied to the ecosystem by light. There are PLANTS (2) to change the light energy into the organic molecule of energy (glucose).