2. Ecology pt2

Question 1

Explain how sewage treatment uses decomposers?

Answer 1

• in sewage treatment plants are designed to provide optimum conditions for microorganisms to break down the human waste
• ideally the final product will be safe to be released into rivers or the sea (but here most of it’s burnt)

Question 2

Explain how biogas generators uses decomposers?

Answer 2

-biogas generators collect animal waste and plant waste which is broken down by bacteria to release a flammable gas that could be used for heating, cooking or to produce electricity

Question 3

All organic molecules within organism contain ………… .

Answer 3

Carbon

Question 4

Explain why the earth is a carbon cycle?

Answer 4

-because the total amount of carbon on the planet is fixed and so must be move between organism and the environment

Question 5

Explain the carbon cycle?

Answer 5

1. CO2 is in the air and dissolved in oceans
2. CO2 Is removed from the air into organic C in green plants by photosynthesis
3. but returns to the air by plant respiration
4. plants feed consumers so there’s organic C in the consumers
5. the consumer does respiration into the air
6. when plants and animals die the organic C in them goes to decomposers who do respiration
7. carbon in fossil fuels comes from dead plants and animals when undergo combustion release CO2

Question 6

What’s the only process in the carbon cycle that removes carbon from the environment and adds it to food chains?

Answer 6

Photosynthesis

Question 7

What are the 2 main processes that return carbon to the atmosphere?

Answer 7

Respiration and combustion

Question 8

Explain how removing trees affect CO2 levels?

Answer 8

• by deforestation your reducing the process that takes on CO2 from the atmosphere
• by burning fossil fuels we are putting more CO2 into the atmosphere from the carbon sinks
• this leads to the greenhouse effect and may cause global warming

Question 9

Explain the water cycle

Answer 9

• transpiration from plants forms clouds
• respiration, sweat and urine as well as rivers, lakes and oceans all evaporate
• it cools and condenses into clouds
• these clouds then precipitate (rain, snow, etc)

Question 10

What does the carbon cycle do?

Answer 10

It returns carbon from organisms to the atmosphere as carbon dioxide to be used by plants in photosynthesis

Question 11

What does the water cycle do?

Answer 11

It provides fresh water for plants & animals on land before draining into seas
Water is continuously evaporated & precipitated

Question 12

What’s the importance of microorganisms in cycling materials through ecosystems?

Answer 12

They return carbon to the atmosphere as carbon dioxide & mineral ions to the soil

Question 13

Why are materials recycled in the living world?

Answer 13

To provide building blocks for future organisms

Question 14

What do farmers & gardeners try to do?

Answer 14

Provide optimum conditions for rapid decay of waste biological material
The compost produced is used as a natural fertiliser for growing garden plants or crops

Question 15

What is mainly burnt in biogas?

Answer 15

• Methane

- anaerobic decay produces methane, so waste from sewage or sugar factories can be used to make biogas on a big scale

Question 16

What produces biogas?

Answer 16

Biogas generators which can be used to produce methane gas as a fuel

Question 17

How does global warming impact biodiversity?

Answer 17

• higher temp causes sea level to rise, it will flood habitats in low lying areas
• as temp increases & rainfall changes the distribution of animals may change. Some might be more widely distributed while others less
• changes in migration patterns(birds might have to migrate further north)
• biodiversity will decrease as some species might become extinct as they are unable to survive the climate

Question 18

Where can pollution happen?

Answer 18

• in water: from sewage, fertiliser or toxic chemicals
• in air: from smoke & acidic gases (sulfur dioxide causes acid rain)
• on land: from landfills & from toxic chemicals (from farming or nuclear waste)

Question 19

How does pollution affect biodiversity?

Answer 19

Pollution kills plants & animals which reduces biodiversity

Question 20

Why is there so much pollution?

Answer 20

• rapid growth of the human population & an increase in the standard of living results in more resources being used
• so more waste is produced
• resources come from the environment, we’re using raw materials more quickly
• unless waste & chemical materials are properly handled, more pollution will be caused

Question 21

What 2 gases are contributing to global warming?

Answer 21

Carbon dioxide

Methane

Question 22

What’s global warming?

Answer 22

• gases in the atmosphere naturally act as an insulating layer
• it absorbs energy that would be radiated into space and re-radiate it in all direction (including back to earth), increasing the temp
• levels CO2 & methane are increasing
• so the earth is beating up too much

Question 23

What do humans use land for?

Answer 23

-building
-quarrying
-farming
-dumping waste
So there’s less land available for other animals

Question 24

What’s peat?

Answer 24

• partly rotted plants gradually build up in a bog to form peat
• the carbon is stored on the plants

Question 25

Why are areas of peat destroyed?

Answer 25

• to produce garden compost
• which reduces the area of this habitat & thus the variety of p,ants, animals & microorganisms that live there (biodiversity)

Question 26

What does the decay or burning of peat cause?

Answer 26

The peat realises carbon dioxide into the atmosphere

Question 27

Why is deforestation happen in topical areas ?

Answer 27

• provide land for cattle & rice fields (farming)

- grow crops for biofuels

Question 28

What problems does deforestation cause?

Answer 28

• less carbon dioxide taken in: cutting down trees realises the carbon
• more carbon dioxide in the atmosphere: when trees are burnt to clear land
• less biodiversity:forest are habitats for lots of species so when they are destroyed some species are in danger of extinction

Question 29

What’s good about a great biodiversity?

Answer 29

-it ensures the stability of ecosystems by reducing the dependence of a species on just another for food, shelter & the maintenance of the physical environment

Question 30

Approximately how much biomass is transferred from each trophic level?

Answer 30

10%