Keywords - Ecosystems Flashcards
Organism
Living thing.
Species
A group of living organisms capable of interbreeding with each other but not with members of other species.
Population
A group of individuals of the same species living in the same place at the same time.
Community
More than one population living in the same area at the same time.
Ecosystem
Communities of organisms that interact with each other and the surround environment.
Ecology
The study of ecosystems.
Producer
Organisms at the base of the food chain that do not feed on other organisms, but rely of photosynthesis for energy. They are also called autotrophs.
Decomposer
Organisms that break down decaying organic matter into inorganic matter (ie. nutrients) to be recycled in the ecosystem.
Photosynthesis
When producers use carbon dioxide, water and sunlight to make chemical energy. This takes place in the chloroplast, in the cells.
Autotroph
A producer.
Heterotroph
A consumer.
Consumer
An organism that relies on other organisms for food.
Herbivore
An animal that exclusively eats plants.
Primary consumer
The first consumer in a food chain, found on the second tropic level. They are also known as first-order consumers or primary consumers.
Omnivore
An animal that eats both plants and animals.
Carnivore
An animal that exclusively eats meat.
Detritivore
An animal that feeds on and breaks down dead plant or animal matter or waste.
Ecological niche
The position of species or populations in their ecosystem in relation to each other.
Competition
The struggle between organisms for food, territory and other factors.
Parasitism
An interaction in which one species lives on or in another, from which it obtains food, shelter and other needs.
Mutualism
A relationship between two organisms in which they both benefit.
Commensalism
A relationship between two species in which one benefits and the other is unaffected.
Interspecific competition
Competition between organisms of the same species.
Intraspecific competition
Competition between organisms of different species.
Predator-prey relationship
A relationship between two species in which one kills and eats the other.
Symbiotic relationship
A close relationship between two organisms of different species. It may benefit or harm one of the partners.
Chemosynthetic
Organisms that produce organic matter using energy released from chemical reactions rather than light.
Food chains/food webs
A diagram that shows feeding relationships and energy flow within an ecosystem.
Tropic level
A level within a food chain, food web, or food pyramid.
Secondary consumers
The second consumer in a food chain.
Energy pyramid
A representation of the amount of food energy within each level of a food chain.
Pyramid of numbers
A representation of the population of an organism at each level within a food chain.
Pyramid of biomass
A representation of the dry mass of organisms at each level within a food chain.
Birth rate
The number of organisms within a population that are born within a particular period of time.
Death rate
The number of organisms within a population that die within a particular time.
Immigration
The number of individuals that move into an area.
Emigration
The number of individuals leaving an area.
Exponential growth
A rapid increase in number or size, represented by a j-shaped graph.
Sigmoid
The shape of a graph that shows a population increasing in number and then reaching a plateau.
Equilibrium
When the birth rate and the death rate cancel each other out, and there is zero population growth.
Carrying capacity
The maximin population size that a particular environment can sustain.
Eutrophication
A form of water pollution involving an excess of nutrients such as nitrates and phosphorus, resulting in algal blooms and possible death of fish and other organisms.
Insecticide
Chemicals used to kill pests that compete with humans for crops.
Fungicide
Chemical used to kill fungal growth.
Herbicide
Chemical used to kill plants that compete with crops for nutrients, water and sunlight.
Fumigant
A chemical in the form of a gas, which is used to kill pests.
Bioaccumulation/magnification
Magnification of concentrations of non-biodegradable substances (eg, pesticides such as DDT) as it is passed along the food chain.
Introduced species
An organism that has been released into an ecosystem where it does not occur naturally.
