Explanation:

An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system.These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the system through photosynthesis and is incorporated into plant tissue. By feeding on plants and on one-another, animals play an important role in the movement of matter and energy through the system. Ecosystems are controlled by external and internal factors. External factors such as climate, parent material which forms the soil and topography, control the overall structure of an ecosystem but are not themselves influenced by the ecosystem. Unlike external factors, internal factors are controlled, for example, decomposition, root competition, shading, disturbance, succession, and the types of species present.  Internal factors not only control ecosystem processes but are also controlled by them. Ecosystems provide a variety of goods and services upon which people depend.