FOOD CHAIN - Series of organisms feeding on one another at various level forms a food chain. or
The sequence of living organism in which one organism eats another is called a Foodchain .
Each step of level of food chain forms a trophic level .
BIOTIC FACTOR - Biotic components of the ecosystem refer to any living component and their interactions.
Example --- soil ,topography ,moisture , etc .
ABIOTIC FACTOR - Abiotic component are those which refer to any non living component in the ecosystem.
Example--- sunlight ,oxygen ,temperature,etc.
ECOSYSTEM -An ecosystem includes all of the living things (plants, animals and organisms) in a given area, interacting with each other, and also with their non-living environments (weather, earth, sun, soil, climate, atmosphere).