1. Individual (Organism): A single living thing.
* Example: A single oak tree, a robin, a bacterium.
2. Population: A group of individuals of the same species living in the same area.
* Example: All the oak trees in a forest, all the robins in a neighborhood, all the bacteria in a single drop of water.
3. Community: All the different populations of organisms living and interacting in a particular area.
* Example: All the oak trees, robins, squirrels, deer, bacteria, fungi, etc. living in a forest.
4. Ecosystem: A community of organisms and their physical environment (including non-living components like soil, water, and air).
* Example: A forest ecosystem, a desert ecosystem, a coral reef ecosystem.
5. Biome: A large-scale ecosystem characterized by specific climate conditions and dominant plant and animal life.
* Example: Tundra, taiga, temperate forest, grassland, desert, tropical rainforest.
6. Biosphere: The sum of all ecosystems on Earth; the part of Earth where life exists.
* Example: The entire planet, including all living organisms and their environments.
