Ecosystems and Material Cycles Flashcards
What is an individual?
A single organism
What is population?
All the organisms of one species in a habitat
What is a community?
All the organisms of different species living in a habitat
What is an ecosystem?
A community of organisms along with the non-living (abiotic) conditions.
What is interdependence?
When organisms depend on each other for things like food and shelter in order to survive and reproduce.
What are the abiotic factors that affect communities?
Temperature
Amount of water
Light intensity
Levels of pollutants
What are the biotic factors that affect communities?
Competition and Predation
What is predation?
A biological interaction where a predator feeds on its prey.
What is a quadrat?
A square frame enclosing a known area (eg 1m2) to compare how common an organism is in two sample areas.
How do you work out the mean number of organisms?
Mean = total number of organisms
————————————-
number of quadrats
What is a gradient?
When abiotic factors change across a habitat.
What does a pyramid of biomass show?
How much the organisms at each level of a food chain would weigh if you put them together and how much energy there is at each stage in the food chain.
What is a food chain?
A series of organisms each dependent on the next as a source of food.
How do you calculate how much energy has been lost?
energy lost = energy available at previous level - energy transferred to next level.
How do you calculate the efficiency of energy transfer?
efficiency = energy transferred to next level / energy available at previous level x 100
