1, autotrophic: green plants synthesize energy-storing organic matter (mainly starch) from inorganic substances such as carbon dioxide and water as their own organic nutrients through photosynthesis, which is called autotrophic. Autotrophic organisms are mainly green plants.
2. Heterotrophication: obtaining the existing organic matter from the outside, transforming it into its own organic matter, and obtaining organic nutrition. This kind of nutrition is called heterotrophic.
Heterotrophic nutrition mainly includes predation, parasitism, saprophytic and other forms.
1, Predation: It is a way for one organism to feed on another.
2. Parasitism: A nutritional way in which an organism lives on the body surface or body of another organism and absorbs nutrients from this organism to maintain its life activities.
3. Saprophytic enzyme: a nutritional way in which an organism absorbs nutrients from the residues of another organism or other organic substances to maintain its own life activities.
Nutrient flow of living things
The energy flow in an ecosystem usually flows in the direction of producer-consumer-decomposer. In the process of energy flow, only a small part of the energy from the previous trophic level in the ecosystem can flow to the next trophic level, forming the organism of the next trophic level due to the waste phenomena such as respiratory consumption, excretion, secretion, inedible, inedible and unused. In fact, in the ecosystem, the waste of a certain trophic level basically enters the saprophytic food chain and is reduced by decomposers, and returns to the environment in the form of heat energy.