P2: Ecology Flashcards
Define ecosystem
A habitat and all the organisms that live and interact in it.
Define community
All of the populations of different species living together in the same habitat.
Define population
All the organisms of the same species living together in the same habitat.
Define interdependence
Where if one species in a community is removed, the whole community can be affected.
Define biotic factor
A factor relating to the living parts of an ecosystem.
Is a new pathogen a biotic or abiotic factor?
Biotic
Give examples of biotic factors.
-Food availability
-New predators
-New pathogens and viruses
-Competition between species
Define an abiotic factor.
A factor relating to the non-living parts of an ecosystem.
Give examples of abiotic factors.
-Light intensity
-Temperature
-Moisture
-Soil conditions (eg pH, mineral content)
-Wind conditions (eg intensity, direction)
-Carbon Dioxide levels
-Oxygen levels
What do animals of the same species compete for?
Food, territory and mates
What are the 3 different types of adaptations?
Structural, behavioural and functional.
What do plants compete with eachother for?
Water, light, mineral ions from the soil.
What is an adaptation?
A specialised feature that allows an organism to survive in their specific environment
What is a structural adaptation?
A physical adaptation, for example a turtle’s hard shell.
What is a functional adaptation?
An adaptation that affects the way an organism’s body works (eg snakes producing venom)
What is a behavioural adaptation?
An adaptation that affects the way an organism acts.
What is an extremophile?
An organism that lives in an extreme environment (for example very hot climate, high salt concentration, high pressure)
What is an advantage of living in an extreme environment?
There is less competition from other organisms.
What type of organism is on the first trophic level?
Producers
What type of levels can you divide an ecosystem into?
Trophic levels
What type of organism is in the top trophic level?
Apex predator.
What do decomposers do?
Break down dead plant and animal matter. A key part of the ecosystem.
What are decomposers typically?
Microorganisms, like bacteria and fungi.
What is biomass?
The amount of living tissue in an organism.
How do decomposers break down dead plants and animals?
Secrete enzymes onto the dead matter. Enzymes break it down into smaller molecules, decomposers absorb the dead matter by diffusion.
As trophic levels increase, what happens to biomass?
It decreases.
What percentage of biomass at one trophic levels gets transferred to the next?
10%
Where is biomass lost?
-Any that isn’t absorbed is egested as faeces.
-Biomass is often lost as waste.
-Lost when organisms respire. (For movement and staying warm)
-Lost in urine.
What is biodiversity?
The variety of all species on Earth or within an ecosystem.
What does the area of each bar in the pyramid of trophic levels show you?
How much biomass is in that trophic level.
Which human activities reduce Earth’s biodiversity?
Waste production, deforestation and burning fossil fuels.
What are humans doing to protect biodiversity?
-Breeding programmes for endangered species
-Making conservation areas out of rare habitats
-Encouraging farmers to add hedgerows and field margins to their fields.
-Recycling
-Reducing deforestation and carbon dioxide emissions
What is a quadrat?
A square frame with an area that’s easy to calculate.
What is the name of the square frame used when calculating the population in an area?
A quadrat.