Ecosystems Flashcards
Term 2, Year 10
Define ‘ecology’
The study of relationships between living organisms and their environment.
Define ‘ecosystem’
A community and its abiotic environment.
Define ‘habitat’
The environment in which a species normally lives.
Define ‘population’
A group of organisms in the same area at the same time.
Define ‘community’
A group of populations living and interacting with each other in an area.
Define ‘species’
A group of organisms that can interbreed to produce fertile offspring.
Levels of ecological organisation
Species—Populations—Community—Ecosystem—Biome
Define ‘biotic factors’
The living aspects of the environment. They consist of other organisms, including members of the same species and of different species.
Define ‘abiotic factors’
The nonliving aspects of the environment, including things such as sunlights, soil, temperature and water.
Explain ‘niche’
The role of a species in its ecosystem. Includes all the ways a species interacts with the biotic and abiotic factors of its environment. Important factors: food it eats and how food is obtained.
Explain ‘competitive exclusion principle’
A given habitat may contain different species, but each species must have a different niche. Two species can’t occupy the same niche in the same place at the same time.
Define ‘autotrophy’
Self-feeding. Organisms synthesise organic molecules from inorganic sources.
Define ‘heterotrophy’
Other source feeding. Obtains organic molecules from other organisms.
Define ‘saprotrophs’
Feeds on non-living organic matter through secreting digestive enzymes and absorbing products.
Define ‘detritivores’
Ingests non-living organic matter.
Define ‘consumers’
Ingests organic matter which is living or recently killed.
Explain the role of decomposers.
Unlock stored nutrients in plants and animals. Breaks down body parts of dead organisms. Converts organic matter into a more usable form. Recycle nutrients and has a role in forming soil.
Explain ‘competition’
- Organisms with a similar niche within an ecosystem will compete where their needs overlap.
- Competition between members of different species= interspecific competition.
- Competition between members of the same species= intraspecific competition.
Explain ‘predatory-prey’
One species kills and eats another. Predator- kills, prey- food.
Explain ‘herbivore-plant’
- Plants cannot run away from predators.
- Protect themselves by using physical structures or chemicals.
Explain ‘symbiotic’
Organisms living together depend on each other (parasitism, mutualism etc).
