7.2 Organisation of Ecosystems Flashcards
Define population
A species that occupy the same habitat.
Define habitat
The place in which an organism lives.
Define community
Populations of different species interacting.
Define ecosystem
The interactions between the biotic and abiotic factors in an area.
What do food chains show?
Food chains show the feeding relationships of different organisms and the flow of energy between the organisms.
Define biomass
The total mass of living material
What are trophic levels?
The stages in a food chain.
What do arrows in a food chain represent?
The direction of biomass transfer.
Describe a simple food chain
Producer - primary consumer - secondary consumer - tertiary consumer
What is a producer?
An organism that makes its own food.
What types of organisms are primary producers?
Photosynthetic organisms like green plants and algae that trap energy from the sun.
What is a primary consumer?
An organism that feed on producers.
What is a secondary consumer?
An organism that feeds on primary consumers.
What is a tertiary consumer?
An organism that feeds on secondary consumer.
What is a predator?
A consumer that kills and eats other animals.
What is prey?
An animal that is killed and eaten by another animal.
Describe the pattern of predators and prey in a stable community
The number of predators and prey rise and fall in cycles
Why are producers the trophic levels?
- Producers provide all biomass for food chain (production of glucose via photosynthesis)
- The rest of the food chain involves the transfer of the biomass
What piece of apparatus is used to measure the abundance and distribution of organisms in an area?
Quadrat
What piece of apparatus is used to study the distribution of organisms across a gradient?
Bell transect
When considering the abundance of organisms what is meant by the term mean?
The average number of organisms.
How is arithmetic mean calculated?
Sum of each number of each organism/the total number of each type.
When considering the abundance of organisms. what is meant by the median?
The organism that represents the middle value when the number of each organism are arranged from lowest to higher.
When considering the abundance of organisms. what is meant by the mode?
The most populous organisms