Chapter 18 biodiverisity Flashcards
what is biodiversity
the variety of species on the earth or within an ecosystem
why is high biodiversity important
as it makes sure the ecosystem is stable as different species depend on each other for food and shelter and maintain the right physical environment for each other
what is reducing biodiversity
- deforestation
- global warming
- waster production
what is increasing population
modern medicine and farming methods as it is causing less people to die
how does an increasing population effect the environment
- it puts pressure on the environment as we take resources from it to survive
- means there is more for a higher standard of living and luxuries to improve QOL → increases use of energy and raw materials during manufacturing processes to meet these demands so more resources are taken from the environment more quickly than they are replaced
How can waste effect biodiversity
Sewage and toxic chemicals from industries can pollute rives affecting animals and plants that rely on it for survival
- chemicals used on land and for farming can be washed into the water affecting animals and plants
- nuclear waste buried underground and household waste in landfill sites can affect biodiversity
- smoke and acidic gases released into the atmosphere can pollute air
What is the temperature of the earth a balance between
- The energy from the sun and the energy it radiates back into space
How do greenhouse gases work
They act as an insulating layer by absorbing energy the earth radiates into space and re-radiates in all directions increasing the temp of the earth
What would happen is there wasn’t a greenhouse effect
Nights would be very cold as there wouldn’t be anything to keep the energy y in
Examples of greenhouses
Methane, carbon dioxide, water vapour and nitrous oxide
Consequences of greenhouse gases
- high temp → sea water will expand + ice caps will melt → rise sea levels → flooding habitats and low lying areas
- high temp → amount of rainfall will change in different areas
- biodiversity ↓ as some species are unable to survive due to changes of The Climate causing them to become extinct
Human use of land
-building
- quarrying
- dumping waste
- farming
Cons of human use land
- Less land available for organisms
What is deforestation
The cutting down of forests
Why is deforestation used
- To clear land for farming
- grow crops so biofuels based on ethanol can be produced
Cons of deforestation
- Less carbon dioxide is taken in: - less plants and trees means dioxie in atmosphere is removed by photosynthesis - less trees lock up carbon dioxide they absorb photosynthesis
- more Carbon dioxide is added into the atmosphere: - Carbon dioxide is released when trees are burnt to clear land - microorganisms feed on bits of dead wood, releasing carbon dioxide as their waste product when respiring
- less biodiversity as habitats are destroyed so many species are in danger of becoming extinct
What are boys
Areas of and that are acidic and waterlogged
What happens to dead plants that live in bogs
They don’t fully decay as the isn’t enough oxygen
So the partly rotted plants build up to form a peat and carbon dioxide is stared in the peats instead of being released
Why are peat bugs drained
- So that the area can be used as farmland
- to be sold to gardeners to be used as compost
- to be cut up and drained to be used as fuel
Cons of draining peat bogs
- When its drained it comes into contact with air and microorganisms start to decompose it, which release Carbon dioxide they respire
- carbon dioxide is released when its burned as a fuel
- destroying bogs destroys habitats of animals, plants and microorganisms reducing biodiversity
Why and who has set up programmes
- They have been set up by concerned citizens and scientists to minimise damage by human activity to ecosystems and biodiversity
Why have breeding programmes been set up
- to prevent endangered species from becoming extinct
What are breading programmes
- Programmes where animals are bred in captivity to make sure that species survive if they die out in the wild
How do breeding programmes boost and re-establish a dying population in the wild
- Individuals are sent into the wild to re-establish and boost a population
What do protection and regeneration of rare habitats programmes do
- They protect and regenerate rare habitats e.g mangroves, coral reefs and mangroves
Pros of protection and regeneration of rare habitats programmes do
Protecting these habitats protects the species preserving the ecosystem and biodiversity
What are field margins
Areas of land around the edges of a field where wild flowers and grass grow
Where does the reintroduction of field margin’s and hedgerows programme take place
- They are introduced in places where only a single type of crop is grown
Pros of reintroduction of field margin’s and hedgerows programme
- hedgerows and field margins provide habitats for a. Wide range of organisms that could survive in a single crop habitat
Aim of reduction of deforestation and carbon dioxide emissions
- To reduce the increase of global warming
Why are people encouraged to recycle
To reduce the amount of waste in landfill sites an the amount of and used for land fill, leaving ecosystems in place
Disadvantages of maintaining biodiversity
- protecting biodiversity cost money
-protecting biodiversity can affect local people’s livelihoods - conflicts between biodiversity and food security
- Conflict between development and biodiversity
Why does protecting biodiversity cost money
As governments pay farmers to reintroduce hedge grows and field margins and it cost money for programmes and regulations to be followed which can lead into conflict between biodiversity and saving money
Why can protecting biodiversity affect people’s livelihoods
As reducing deforestation can cause unemployment to people working in the tree falling industry which can affect the ecosystem more people would be moving to find jobs elsewhere
Why can biodiversity cause conflict between food security
As certain organisms are seen as pests which farmers kill to protect their crops and livestock so more food is produced this can affect the food chain and biodiversity
Why is there conflict between biodiversity and development as been used for development
As land is in high demand so untouched land with high biodiversity
What are tropic levels
Different stages of a food chain which consist of 1 or more organisms with a specific role in the food chain
Tropic level 1
Contains producers which make their own food by photosynthesis using energy from the sun (that’s why there are called producers)
Tropic level 2
Contains primary consumers which are herbivores who only eat plants and algae
Trophic level 3
Contains secondary consumers which are carnivores who only eat meat (primary and secondary consumers)
Trophic level 4
Contains tertiary consumers which are carnivores that eat secondary consumers and apex predators
Why are decomposers important
As they breakdown uneaten remains, dead plants and animals
How do decomposes decompose things
They secrete enzymes which break down dead stuff into small soluble food molecules which diffuse into microorganism
What does each bar of a pyramid of biomass show
It shows the relative mass of each trophic level
Relationship between trophic level, biomass and energy
As the trophic distances the biomass and energy decreases
What is dry biomass
The weight of an organism when it is killed and dried
What percentage of light is absorbed by producers and used in photosynthesis
1%
What is biomass
The living tissue of an organism
What is biomass
The living tissue of an organism
Why does biomass decrease
- Not all of the material an organism ingest is absorbed and some it is egested a faeces
- some of the biomass is converted into waste products from metabolism and released urea
- a large amount biomass is used for respiration to release energy and waste products
what is food security
having enough food to feed a population
what factors can threat food security
- changing diets in developed countries
- pests and pathogens
- high input costs of farming
- increasing the population
- conflicts
- changes in the environmental conditions
how does changing diets in developed countries affect food security
as the diets in developed countries change, the demand for certain food to be imported increase, this means that already scarce food resources become more scarce
how does pests and pathogens affect food security
- it can affect farming and this can result in the loss of crops and livestock and can lead to widespread famine
how can changes in the environmental conditions affect food security
it can affect farming and this can result in the loss of crops and livestock and can lead to widespread famine
how can high input costs of farming affect food security
- it can make farming too expensive for people in some countries as they will find it hard to start or maintain food production this will result in not enough people producing food in these areas to feed people
how can high input costs of farming affect food security
- it can make farming too expensive for people in some countries as they will find it hard to start or maintain food production this will result in not enough people producing food in these areas to feed people
how can conflict affect food security
conflict in some parts of the world affect the availability of food and water
why are fish stocks declining in oceans
as we fish too much
what problems does overfishing cause
its causing fishstock to decline in oceans and this means that there is less fish for us to eat, oceans food chains are affected and some fish species may disappear
how do we solve the problems overfishing is causing
we have to carry out a sustainable food production by maintaing fish stocks at a level where fish continue to breed
what ways can fish stocks be maintained
- fishing quotas
- net size
how can fishing quotas maintain fish stocks
this limits on the number and size of fish that can be caught in certain areas, which prevents overfishing
how can net size maintain fish stocks
- this limits the mesh size of the fishnet, depending on what’s being fished, this reduces the number of unwanted and discarded fish as using a bigger mesh size will let unwanted species to escape and means that younger fish will slip through the net allowing them to reach a breeding age
what makes farming more efficient
limiting the movement of livestock and keeping them in a temperature-controlled environment, as this reduces the transfer of energy, making farming more efficient as the animals use less energy moving and controlling their body temperature, so more energy is available for growth so more food can be produced from the same input of resources
methods in making farming more efficient
- livestock can be factory farmed by raising them in small pens
- fishes can also be factory farmed in cages where their movement is limited
- animals are fed high protein food to increase their growth
how to work out the efficiency of biomass transfer
gain in biomass/ total biomass taken in x100
how to work out biomass lost
biomass available at trophic level - biomass available at previous level
disadvantages of methods in making farming more efficient
- animals are so kept close together that diseases can spread between them easily
- some people think that making animals live in unnatural and uncomfortable conditions are cruel
what are the benefits of using modern biotechnology
- large amounts of microorganism can be cultured industrially under controlled conditions in large vats to be used as a food source
what are the benefits of using modern biotechnology
- large amounts of microorganism can be cultured industrially under controlled conditions in large vats to be used as a food source
what are mycroprotiens used for
to make high protein meat substitutes for vegeterian meals
what is mycoprotein made out of
the fungus Fusarium, which is grown aerobic conditions on glucose syrup which it uses a food
how is mycoprotein produced
by fungal biomass being harvested and purified
what is genetic engineering
transferring a useful gene from one organism to another
steps on making human insulin from genetically engineered bacteria
1) a plasmid is removed from a bacterium
2) the insulin gene is cut out of a human chromosome using a restriction enzyme, the cut leaves one of the DNA strands with unpaired bases called sticky ends
3) the plasmid is cut open using the same restriction enzyme leaving the same sticky end
4) the plasmid and the human gene are mixed together
5) Ligase ( an enzyme) is added, this joins the sticky ends together to produce a recombinant DNA
6) the recombinant DNA is inserted into a bacterium
7) the modified bacterium is grown in a vat under controlled conditions and you end up with millions of bacteria that produce insulin, the insulin is then harvested and purified to treat people with diabetes
what does a restriction enzyme do
- recognises specific squences of the DNA at cut the DNA at these points, the cut leaves on DNA strands with unpaired bases
what is recombinant DNA
two different bits of DNA stuck together
benefits of biotechnology
- gentically modified plants can be produced that are resistant to pests, improving crop yield
- ## crops can be genetically modified to grow better in drought conditions improving crop yield and some crops can be modified to provide more nutrional value
disadvantages of biotechnology
- people go hungry because they cant afford food not because they’re isnt any food about, so people argue that they need to tackle povery first
- some countries may go dependent on companies who see genetically modified seeds
- sometimes poor soul is the reason why crops fail and why genetically modified crops wont survive
- can interrupt natural environment
- involves changing the genetic material of organisms
