SB9 Ecosystems Flashcards
What is a population?
A group of one species living in an area
What is a community?
All the different organisms living and interacting with one another in a particular area.
What is a habitat?
The place where an organism lives.
What is an ecosystem?
All the living organisms and the non-living components in an area.
What is a biotic factor?
A living factor that affects an ecosystem.
What is an abiotic factor?
A non-living factor that affects an ecosystem.
Name 2 examples of biotic factors.
Competition, predation, pathogens
Name 4 examples of abiotic factors.
Temperature, light intensity, water, pH, mineral content, aeration
What is a producer?
An organism that uses light energy or a chemical reaction to produce its food.
What is a consumer?
An organism that feeds on another organism for a source of food.
What is a predator?
A consumer that eats another consumer.
What is prey?
A consumer that is eaten by another consumer.
What is interdependence?
Where organisms in an area need each other for resources e.g. for food and shelter
Name 4 examples of interdependent relationships in an ecosystem?
Competition, predation, parasitism, mutualism
Name 4 resources that plants could compete for.
Light, space, water, minerals
Name 4 resources that animals could compete for.
Food, water, territory, mates for reproduction
What is mutualism?
A relationship between two species where both species benefit.
What is parasitism?
A relationship between two species where the parasite benefits but the host is harmed.
What does abundance measure in an ecosystem?
How common organisms are in the ecosystem.
What does distribution measure in an ecosystem?
Where organisms are found in the ecosystem.
What is a representative sample of an ecosystem?
A measurement of the organisms that reflects the true abundance and distribution of species in an ecosystem.
What 2 things can we do to make samples more representative of an ecosystem?
Increase the number of samples and use a random sampling method.
What method of sampling should be used to estimate the abundance of a species in an ecosystem?
Random sampling using grid coordinates.
What is random sampling?
Collecting samples in an unbiased way i.e. no human choice of where a sample is taken.
What is a quadrat?
A square frame used to collect samples of plants or slow moving animals in an ecosystem.
What is the formula for estimating the abundance of a species in an ecosystem?
abundance estimate = total organisms in all quadrats × ( total area sampled ÷ total area of quadrats)
What method of sampling should be used to measure the distribution of a species in an ecosystem?
Systematic sampling using a belt transect.
What is a belt transect?
A straight line that runs parallel with a suspected change in a factor along which samples can be taken.
What 2 measurements are made at each sample along a belt transect?
Population of each species, measurement of abiotic factor
What is biomass?
Mass of tissues in an organism
What is a trophic level?
Feeding level in a food chian, such as producer or primary consumer.
