B17 - Biodiversity And Ecosystems

Question 1

Ecosystem

Answer 1

The interaction of a community of living organisms with the non-living parts of their environment.

Question 2

Biodiversity

Answer 2

The variety of all the different species of organisms on earth, or within an ecosystem.

Question 3

Why is biodiversity important?

Answer 3

Ensures the stability of ecosystems by reducing the dependence of one species on another.

Question 4

What are organisms dependent on each other for?

Answer 4

For food, shelter and the maintenance of the physical environment.

Question 5

What is extinction?

Answer 5

When there are no more living members of a species left.

Question 6

Why is it important to prevent the extinction of a species?

Answer 6

They may provide useful substances to
humans, the extinction may effect another species in the food chain, there is a duty to preserve species for future generations.

Question 7

Why is more waste being produced?

Answer 7

More people, increase in standard of living

Question 8

Where can pollution occur?

Answer 8

• In water, from sewage, fertiliser or toxic chemicals
• In air, from smoke and acidic gases
• On land, from landfill and from toxic chemicals.

Question 9

What can end up in water, which causes pollution?

Answer 9

Sewage, fertiliser or toxic chemicals

Question 10

What problems does carbon dioxide cause?

Answer 10

Greenhouse effect and global warming

Question 11

What problems can nitrogen oxide and sulfur dioxide cause?

Answer 11

Acid rain.

Question 12

What problems can acid rain cause?

Answer 12

Damage trees, lower pH or lakes and rivers, damage stone and metals.

Question 13

What causes smog?

Answer 13

Tiny particulates in smoke.

Question 14

What chemicals from farmland pollute water?

Answer 14

Pesticides, herbicides, fertilisers.

Question 15

How can toxic chemicals end up in the water supply?

Answer 15

Released illegally by industry.

Question 16

What happens when fertilisers end up in the water supply? (potential 6 marks)

Answer 16

-Large growth of algae,
-death of algae,
-microbes decay waste,
-increased respiration by microbes,
-decreased oxygen in water,
-organisms living in water die from lack of oxygen.

Question 17

What is put in landfill?

Answer 17

Any rubbish that is not recycled.

Question 18

Human use of land

Answer 18

Building, quarrying, farming, disposing waste.

Question 19

Why is demand for land rising quickly?

Answer 19

More people and increased standard of living

Question 20

What are bogs?

Answer 20

Wet areas of land without trees with lots of moss growing in them.

Question 21

What are the conditions in bogs like?

Answer 21

Acidic and low in nutrients.

Question 22

What is the bog made from?

Answer 22

Partially-decayed plants.

Question 23

Why is peat a non-renewable resource?

Answer 23

It takes a very long time to form.

Question 24

What is peat used for?

Answer 24

Burned as fuel, or added to soil by gardeners for fertiliser.

Question 25

Why does peat release carbon dioxide when it is added to the soil?

Answer 25

-Mixed with oxygen -Microbes begin to break it down, they respire as they do, releasing carbon dioxide.

Question 26

Why has deforestation occurred?

Answer 26

Provide land for cattle and crops, grow crops for biofuel, to provide materials for building, fuel and paper

Question 27

Why has deforestation increased in more recent years?

Answer 27

Increased population and development of large industrial machinery

Question 28

Why is deforestation reducing biodiversity?

Answer 28

It is destroying habitats and kills different species.

Question 29

Why does deforestation increase soil erosion?

Answer 29

Roots stop holding the soil in place and so it gets washed and blown away

Question 30

How does deforestation affect atmospheric composition?

Answer 30

Increases carbon dioxide as there is less photosynthesis and more burning.

Question 31

Consequences of global warming

Answer 31

Melting ice caps, rising sea levels, expansion of seawater, flooding of land, more extreme weather, changes in weather patterns, habitats changing, migration patterns changing, extinction.

Question 32

Explain why it took a while for the theory of global warming to be accepted by most.

Answer 32

Lack of evidence, more evidence now collected, which has been peer reviewed.

Question 33

Describe the different ways that humans have a negative impact on ecosystems.

Answer 33

Increased waste and pollution, destruction of peat bogs, use of land for farming, building, quarrying, dumping waste, deforestation, increased air pollution.

Question 34

Describe the different ways that humans have a positive impact on ecosystems.

Answer 34

Breeding programs, protection of rare habitats, reintroduction of field margins, reducing deforestation, recycling materials.

Question 35

Explain how we can reduce the amount of waste going to landfill.

Answer 35

Reduce Reuse Recycle