B18(Biodiversity And Ecosystems) Flashcards
What is biodiversity
Biodiversity is the variety of different species of organisms on Earth, or within an ecosystem
Different species depend on each other for…
Food
Shelter (eg. birds nesting in trees)
Maintenance of the physical environment
What are the human activities reducing biodiversity
Producing waste
Deforestation
Global warming
What are the sources of water pollution
What is bioaccumulation
The increase in concentration of a toxic chemical in a particular organism over time
What is biomagnification
The increase in concentration of a toxic chemical the higher the organism is in the food chain
What is the process of eutrophication
-excessive nutrients from fertilisers run off from land into water
-aquatic plants flourish growing rapidly
-algae also show rapid growth
-algae bloom prevents sunlight from reaching aquatic plants causing water oxygen levels to fall
-aerobic respiration of decomposers reduces dissolved oxygen further
-death of organisms requiring dissolved oxygen in water
What are the sources of land pollution
What are the sources of air pollution
What is the increasing human land use
What are peat bogs
Bogs are areas of land that are waterlogged and acidic – plants living in bogs do not decay fully when they die due to a lack of oxygen
Why are peat bogs being destroyed
Peat bogs are drained so that the area can be used for farming
Peat can be dried and used as a fuel
Peat can be used to produce compost for gardens or farms to increase food production
What are the negative impacts of peat bogs being destroyed
-Carbon dioxide is released into the atmosphere
-peat bogs take so long to form that peat is effectively a non-renewable energy source
-reduces biodiversity
What are the consequences of deforestation
What are the main greenhouse gases
Water vapour
Carbon dioxide
Methane
Nitrous oxides
CFCs
How does the greenhouse effect work
The Sun emits rays that enter the Earth’s atmosphere
The heat bounces back from the Earth’s surface
Some heat is reflected back out into space
Some heat is absorbed by greenhouse gases and is trapped within the Earth’s atmosphere – this is normal
What are the consequences of global warming
-Ocean temperatures increasing
-Increasing temperatures
-Changes in or loss of habitats
-Decreases in biodiversity
-Increases in migration of species to new places
What are the Methods to reduce negative impact on ecosystems & protect biodiversity
What are trophic levels
Trophic levels describe the position of an organism in a food chain, web or pyramid
What are the different trophic levels
What is biomass
Biomass is the mass of living tissues that a plant or animal is made up of
What are pyramids of biomass
shows the relative biomass at each trophic level in a food chain
How is biomass transferred
-Energy flows from the Sun to the first trophic level (producers) in the form of light
-Producers convert light energy into chemical energy
-When primary consumers consume producers, they break down the biomass of the producer and use the chemical energy to increase their own biomass
-When secondary consumers consume primary consumers they break down the biomass of the primary consumer and use the chemical energy to increase their own biomass
How much biomass is passed on to the next trophic level
10%
What are the losses of biomass due to
-Organisms rarely eat every part of the organism they are consuming
-Not all the ingested material is digested and absorbed
-Some absorbed material is lost as waste
What is the equation to calculate the efficiency of biomass transfer
What is food security
having enough food to feed a population
What are the Biological factors threatening food security
How can The efficiency of food production be improved
-limiting their movement
-controlling the temperature of their surroundings
What are the Advantages & disadvantages of modern farming techniques
What is the cause for the decline of fish stocks
Overfishing
What are the consequences of overfishing
-Some species of fish completely disappearing in certain areas
-Ocean food chains being disrupted
-Fewer fish for human consumption
How to maintain fish stocks
-Sustainable fisheries
-Control of net size
-Increasing the size of gaps
-fishing quotas
What is biotechnology
involves the alteration and use of living organisms to produce products for human use
What is mycoprotein
the process of creating food from a fungus
How is mycoprotein produced
-These fermenters are large vats that can be kept at the optimum pH and temperature for Fusarium to grow
-The fungus is grown in aerobic conditions and provided with glucose syrup as a food source
-The fungus grows and multiplies within the fermenter
The fungal biomass is then harvested and purified to produce mycoprotein
What are modern biotechnology techniques
-genetic modification
-insulin production
-GM crops