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An ecosystem is a community of living organisms interacting with their physical environment as a functional unit. The living components, called biotic factors, include producers, c...
A food chain is a linear sequence of organisms through which nutrients and energy pass as one organism eats another, beginning with producers and ending with top consumers. In cont...
A biome is a large-scale community of organisms classified primarily by the dominant vegetation and characterized by adaptations to that particular environment. Tropical rainforest...
Population ecology examines how groups of organisms of the same species change over time and space. Population density measures the number of individuals of a species per unit area...
Species do not live in isolation; they interact with one another in many ways. Symbiosis refers to a close, long-term biological interaction between two different species living in...
Biodiversity refers to the variety of life at all levels of biological organization, including genetic diversity, species diversity, and ecosystem diversity. Species richness is th...
Human activities have profoundly altered Earth's ecosystems. Deforestation, the large-scale clearing of forests for agriculture, logging, or urban development, leads to loss of bio...