Biodiversity Flashcards
What do photosynthetic organisms produce?
Biomass for life on earth
What is ‘mean’?
Average
What is the median
Number in the middle of a sequence
What is mode
The most often number in a sequence
What is biodiversity?
The variety of different species in a given ecosystem
What are positive interactions with biodiversity?
- breeding programs for endangered species
- protection of rare habitats
- reintroduction of field margins and hedgerows in farms
- reduction of deforestation + co2 emissions
- recycling rather than using landfill
What are negative interactions with an ecosystem?
-deforestation
-pollution
What are anthropogenic threats?
Human threats to biodiversity
What causes water pollution?
-sewage
-fertiliser
-toxic chemicals
What causes air pollution?
-smoke
- acidic gases (silicon dioxide, co2, methane
What is meant by decomposition?
Releasing nutrients (mineral ions) back into the environment
What are meant by decomposers?
A bacteria and fungi which breaks down dead organisms into waist material
What conditions do you need for decay?
-warmth
- moisture
- oxygen
What is saprotroph?
An organism that gains nutrients from dead organic matter
What is the carbon cycle (definition)
The constant cycling of carbon between the environment and living things.
What are the steps in the carbon cycle?
- co2 is in the air (and dissolved in water)
- photosynthesis removes co2 from the environment and converts it to oxygen
- animals eat the plants that use photosythesis
- animals release co2 in respiration
- animals and plants die and decompose to make fossils fuels / carbon in the ground.
- factories dig up carbon and fossil fuels and burn it (combustion)
- during combustion co2 is released into the air
What is a producer?
An organism that makes its own food by photosynthesis
Why do some plants eat animals (carnivorous plants : Venus fly trap)
- some soils contain low nitrates especially when waterlogged, so plants eat bugs and animals with high levels of nitrates.
What is an abiotic factor?
Non living factors that affect living organisms
What is interspecific competition?
Competitions between species
What are examples of abiotic factors?
-light intensity
- temperature
- moisture levels
- soil PH and mineral content
- wind intensity and direction
- availability of oxygen
- availability of co2
What are biotic factors?
Factors that effect living organisms and communities
What are examples of biotic factors?
- availability of food
- new pathogens or parasites
- new predators
- interspecific competition
What is quantative sampling?
Mean number of organisms per m2
Using the carbon cycle , what are ways CO2 is released into the environment?
- respiration from animals
- decay and decomposition of organic matter
- combustion
- carbon compounds in fossil fuels burned (combustion)
How does peat release CO2?
- when burned as a fuel, releases CO2 during combustion
- releases CO2 when reacts with air as saprotrophs (bacteria that decompose organic matter) respire and release CO2
Why is biodiversity good and how can biodiversity be presented as data?
- high biodiversity ensures stability of ecosystems by reducing the dependence of one species on another
- food webs
What is the negative impact of the growth of human population on the earth?
- as more resources are created to sustain large population, more waste produced + more pollution
Why is there a growing human population?
- improved medicine and healthcare decreases death rate
- improved technology makes better food which increases birth rate
What other types of species do humans rely on?
- photosynthetic organisms (for oxygen)
- pollinators (for food)
- plants (for medicine)
What three things do species depend on each other for?
- food
- shelter
- maintenance of environment
What are examples of human land use?
- building
- extraction of natural resources (quarrying)
- farming
- landfill
What negative actions decrease biodiversity?
- producing waste
- deforestation
- global warming (flooding, coral bleaching, extreme weather)
