1).Ecology is the scientific analysis and study of interactions among organisms and their environment,such as the interactions organisms have with each other and with their abiotic environment.
2).Ecosystem is defined as a dynamic system which includes both organisms as biotic and abiotic component influencing the properties of each other. These are necessary for maintenance of life.
3).Producers are those who make their own food by the process of photosynthesis.
4).A herbivore is an animal which eats plants as the main component of its diet.A carnivore is an organism that derives its energy and nutrient requirements from a diet consisting mainly of meat(animal tissue).An omnivore is an animal whose species normally derives its energy and nutrients from a diet consisting of variety of food sources like plants,meat(animal tissues),etc
5).All the living components including the microorganisms,plants,animals and even human beings are called biotic components of environment.All non-living components like air,water,soil,temperature,humidity are called abiotic components of environment.Though they are non-living they are responsible for life.
6).Biodiversity is the degree of variation of life.It is the measure of variety of organisms present in different ecosystems.
7).The place that an animal occupies in a biotic community which expresses its functional status is called niche.In other words the functional aspect of a species is also referred as ecological niche.
8).All organisms need to feed to get energy.The food chain makes a relationship between organisms.The chain in which the energy is transferred from one trophic level to another is called a food chain.A food web is a linking of many food chains.Simple food chains normally do not occur in nature.Its because one organism may operate at different levels of food chains.
9).Decomposers are organisms that breakdown dead or decaying organisms, and in doing so carry out the natural process of decomposition.