7 Ecology Trilogy Flashcards Preview

AQA Biology Paper 2 11BT > 7 Ecology Trilogy > Flashcards

Flashcards in 7 Ecology Trilogy Deck (49)
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1
Q

Define ‘biodiversity’.

A

A measure of the variety of all the different species of organisms within an ecosystem

2
Q

What are two major problems from the exponential increase in human population?

A

More natural resources are used up, human’s produce more waste, which leadfs to a decrease in biodiversity

3
Q

State four sources of land pollution.

A

Human sewage, household wastes, Industrial wastes, pesticides and herbicides in farming

4
Q

How does land pollution affect biodiversity?

A

Less (clean) food available / Loss of habitat / Global warming leading to migration

5
Q

How does human sewage contribute towards land pollution?

A

Harmful microbes and bad chemicals lead to spread of diseases on land

6
Q

Explain how household and industrial wastes pollute land.

A

Take up space in landfills, Toxic or radioactive chemicals which poison soils and desroys habtitats.

7
Q

State four sources of water pollution.

A

Untreated sewage, fertilisers, industrial wastes, pesticides and herbicides

8
Q

Name the situation where a body of water has low oxygen levels, leading to marine organisms’ death.

A

Eutrophication

9
Q

What causes eutrophication?

A

Fertilisers leaked into lakes, excess nutrients causes excessive plant growth, leading to an increase in competition/algae covering water surface (less light allowed into lake for water plants)

10
Q

What is bioaccumulation?

A

Accumulation of chemicals in an organism

11
Q

Name a chemical that gets built up in organisms in bioaccumulation.

A

Heavy metals/Fertiliers/Pesticides/Herbicides

12
Q

Why is bioaccumulation bad?

A

Chemical concentration increases with each trophic level. This may reach fatal levels when they get to the top consumer.

13
Q

Name a source of air pollution.

A

Combustion of fossil fuels

14
Q

How is acid rain formed?

A

Acidic gases released from burning fossil fuels are dissolved in rain water

15
Q

Name three acidic gases released from burning fossil fuels.

A

Carbon dioxide + sulphur dioxide + Nitric oxides

16
Q

Give 3 effects of acid rain.

A

Kills plants; Destroys roots in soil; Acidifies bodies of water, killing marine organisms; Affects neighbouring countries; Acid snow kills young plants

17
Q

What is global dimming?

A

Particulates made from combustion covers the atmosphere, reflecting sunlight so less light reaches the surface

18
Q

What causes global dimming?

A

Particulates

19
Q

Name two conditions that particulates can cause.

A

Global dimming + Smog

20
Q

Explain how global dimming affect plant growth.

A

Cooling temperatures + Less sunlight –> Plants die due to insufficient photosynthesis

21
Q

What is smog?

A

Particulates + Acidic gases

22
Q

How does smog affect our health?

A

Inhaling particulates damages our lungs and cardiovascular systems

23
Q

Name a toxic gas that is released from incomplete combustion.

A

Carbon monoxide

24
Q

How does carbon monoxide cause an effect in our body?

A

Binds to haemoglobin irreversibly –> less Hb available to bind to oxygen –> suffocation

25
Q

Suggest two ways to reduce air pollution.

A

Use low-sulphur fuels / Set strict emission levels / Use biofuels / Use exhaust gas filters in power stations / Catalytic converters in cars

26
Q

Suggest two alternative power source that reduces air pollution.

A

Low-sulphur fuels / Biofuels / Renewable energy

27
Q

What is meant by a ‘carbon sink’?

A

A place that stores carbon

28
Q

Give two examples of good carbon sinks.

A

Forests + Peat bogs

29
Q

Give a reason for deforestation.

A

Provide resources / Provide land for agriculture / Provide land to make biofuel

30
Q

Give a reason for peat destruction.

A

Provide fuel/garden compost

31
Q

Name two major impacts deforestation and peat destruction have on the environment and our biodiversity.

A

More CO2 release (more global warming and acid rain) + Decrease biodiversity

32
Q

How does a decrease in biodiversity have a negative impact on humans?

A

Loss of potential new sources of food and medicine / Loss of resources

33
Q

Name three major greenhouse gases.

A

Carbon dioxide + Methane + Water vapour

34
Q

Suggest a source of carbon dioxide release.

A

Burning fossil fuels/Deforestation/Peat destruction etc.

35
Q

Suggest a natural source of methane.

A

Growing rice and cattle

36
Q

What is the greenhouse effect?

A

Thermal energy from the sun reaches the earth and some are reflected. Greenhouse gases absorb these reflected thermal energy and keep Earth warm

37
Q

Any greenhouse effect is bad for the Earth. True or false? Explain.

A

FALSE (essential to keep earth warm, vital for life)

38
Q

What causes global warming?

A

Too much greenhouse gases –> trap too much heat within atmosphere (enhance greenhouse effect)

39
Q

State three effects of global warming.

A

Climate change / Ice caps melt / Warming seas dissolve less carbon dioxide

40
Q

What biological consequences does climate change bring about?

A

Changes in migration pattenrs and species distribution

41
Q

What biological consequences does melting of ice caps bring about?

A

Loss of habitat –> some animals die –> reduce biodiversity

42
Q

State three methods to maintain biodiversity.

A

Breeding programmes / Protect and regenerate rare habitats / Grow hedgrows / Reduce deforestation and CO2 emission / Recycling

43
Q

Why is important to protect and regenerate rare habitats?

A

To allow specifically adapted species to live in nature again (as they cannot live in “normal” conditions)

44
Q

Give one impact on the environment by removing hedgrows.

A

Soil erosion / Reduce soil fertility

45
Q

What problem is solved by recycling?

A

Avoiding landfills becoming full, which leads to pollution

46
Q

Suggest a possible challenge in breeding programmes.

A

Animals do not reproduce easily or fast / Must avoid inbreeding / No natural habitats for them to return to

47
Q

Suggest a possible challenge in reintroducing hedgerows.

A

Loss of land available for growing crops (less profit)

48
Q

Suggest a possible challenge in buying lands to restrict deforestation.

A

Resistance from businesses to maintain profit or demand / Money needed

49
Q

Suggest a possible challenge in reducing carbon dioxide emission.

A

Lack of scientific research on better engines or methods to reduce emission