P2B9 - Ecosystems and Material cycles

Question 1

Whats an ecosystem?

Answer 1

All organisms AND the environment inwhich they live

Question 2

Whats a populaytion?

Answer 2

All organisms of a particular kind living in the same area

Question 3

Whats a community?

Answer 3

All organisms that live + interact within an ecosystem.

Question 4

Whats interdependence?

Answer 4

How all organisms that live together for survival

Question 5

Whats the structure of an ecosystem?

Answer 5

Individual organism - Population - Community - Ecosystem

Question 6

What does ecosystem diversity depend on?

Answer 6

The amount of resources available and competition betwen the diff populatuins

Question 7

What is abiotic and biotic?

Answer 7

Abiotic is non living
Biotic is living

Question 8

Why is interdependence vital?

Answer 8

It limits competition and increases biodiversity

Question 9

What is symbiotic also known as?

Answer 9

Mutualistic.

Question 10

What is abiotic caused by?
Examples of abiotic factors?

Answer 10

Environment that affect organisms
Temp
Water
Ph nutrients in soil
Light
Pollution

Question 11

What is biotic?
Example?

Answer 11

Living organisms in an ecosystem
Predators
Competition

Question 12

What are the 2 methods of sampling populations?

Answer 12

• random quadrat sample
• Belt transect

Question 13

How to calculate a sample ppulation using quadrats?

Answer 13

N.o of organisms in all quadrats
X
total size of area / Total area of quadrate=s

Question 14

How do natural abiotic factors affect communities?

Answer 14

If abiotic factors change then the abundance of organisms will change as their characteristics are no longer beneficial and could affect distribution

Question 15

What are pollutants?
Examples

Answer 15

All substances that cause harm in the environment.
Poisons
Plastics
Fertilisers resulting in Eutrophication

Question 16

What are the stages of Eutrophication?

Answer 16

1. Fertilisers in water increases the conc of nitrates and phosphates
2. This causes algae to grow on surface of water which blocks sunlight
3. Plants underwater cannot photosynthesise, so less oxygen in water
4. Causing marine life to
   die bc they cannot respire
5. Due to decay, increase in bacteria and biodiversity decreases.

Question 17

How can competition affect communities?

Answer 17

In large communities, many biotic factors affect predator and prey number.
In small communities, predator - prey cycles can be seen.

Question 18

Why would prey pop decrease while predator pop decreases?

Answer 18

Because theres less food and more competition within the predator population

Question 19

What are the 3 feeding relationships?

Answer 19

Trophic (Predator/prey)
Parasitism (a parasite + a host)
Mutualism (symbiotic - both benefit)

Question 20

How does parasitism affect the survival of some organisms? eXAMPLES?

Answer 20

The host provides food for the parasites but can survive for a long period.
lice
tapeworms live inside hosts intestines causing malnutrition.

Question 21

Why are bees and anemone an example of mutualism?

Answer 21

Bees + flowers
1. Bees get food from the flower (nectar)
2. Flower gets pollinated

Anemone + clownfish
1. Clown fish get shelter + protection from anemone
2. Anemone is kept clean by the clown fish

Question 22

What if fish farming?

Answer 22

Growing fish for food in a defined space

Question 23

What are the advantages of fish farming?

Answer 23

Reduces overfishing which maintains biodiversity
More fish can be farmed (food)

Question 24

What are the disavabateges of fish famring?

Answer 24

Can harm organisms due to food/faeces which reduces biodiversity.
Parasites/disease introduced to ecosystem which reduces biodiversity .

Question 25

What are indigenous and native species?

Answer 25

Organisms that have always been in an area.

Question 26

Why might introducing a non-indigenous species to an area affect the indigenous species there?

Answer 26

If it increases competition = biodiversity decreases Non indigenous species can introduce parasites.

Question 27

How does eutrophication affect abiotic factors?

Answer 27

Nitrate conc of water increase Oxygen levels of water decrease

Question 28

How does eutrophication affect biotic factors?

Answer 28

Algae grows RAPIDLY on surface Underwater plants do less photosynthesis Marine life die bc cant respire Bacteria (decomposers) breakdown dead matter

Question 29

What is conservation?

Answer 29

The protection of a habitat or species to prevent damage.

Question 30

What are ways species can be conserved>

Answer 30

Captive breeding Legal protection of habittas Links between habitats so they can roam easily and widely to find mates Education Rebuild habitats

Question 31

How can deforestation affect biodievery??

Answer 31

Higher light intensity, no shade or shelter Increases wind as no wind break from trees] Increased risk of flooding = eutrophication + unstable ground Less nutrients in soil Less biodiversity as more competition

Question 32

What materials cycle thru ecosystems?

Answer 32

1. water - precipitation etc 2 carbon - co2 containing compounds 3 nitrogen - lightning, nitrogen fixing bacteria

Question 33

What does the water cycle describe?

Answer 33

How water moves thru the abiotic and biotic parts of an ecosystem

Question 34

Whats the water cycle

Answer 34

Water that moves thru soil and rocks back to ocean - Water in ocean (liquid h20) - Water evaporates in oceans, lakes and rivers to form water vapour (gas) - As air rises it cools so water vapour in it condenses to form clouds (liquid) - As water droplets get too large and dense they fall as rain or snow (precip) - Ground water

Question 35

How is potable drinking water produced?

Answer 35

1. Water from water cycle is filled to remove insoluble solids 2. Heat treatment to kill microorganisms 3. chLORINation/treat with other chemicals to clean water and improve taste OR A still can be used to collect water Desalination extracts salt from seawater Fractional distillation to extract water from air

Question 36

What is a decomposer? example

Answer 36

Microorganisms that cause decay (breakdown of substances) include fungi and bacteria which breakdown CARBON CONTAINING COMPOUNDS

Question 37

how do fossil fuels form and what happens if they dont?

Answer 37

dead animals and plants inn the right conditions. If not, decomposers breakdown the dead animals/plants + they also respire, releasing CO2 into atmosphere.

Question 38

Why do plants need nitrates?

Answer 38

plants need nitrogen from environment, so that they can convert glucose to nitrogen-containing compounds such as proteins and nucleic acids. (dna)

Question 39

what are ways farmers increase the conc of nitrates in soiL?

Answer 39

Artificial fertilisers Natural fertilisers Crop rotation legume foods Fallow land

Question 40

advantages of artificail fertlisers?

Answer 40

easy to use known amount of nutriwnts on label dissolives easily in soil

Question 41

disadvantages of artfiicial fertilisers?

Answer 41

Eutrophication decreases biodiveristy

Question 42

Advantages of natural feertilisers?

Answer 42

Make use of natural waste Free/cheap

Question 43

disadvantes of natura; fertiliserd?

Answer 43

Spread (eg manure) weeks in advance as soil bacteria needs to break down proteins into nitrates. Less oxygen in soil

Question 44

advanatges of crop rotation legume foods?

Answer 44

Doesnt use fertilisers Crops still produced

Question 45

Disadvantges of crop rotation legume foods?

Answer 45

Less money as less demand for legume

Question 46

advantages of fallow land?

Answer 46

No cost of maintenance or fertilisers

Question 47

disadvantages of fallow land?

Answer 47

no crops = no money

Question 48

What is food security?

Answer 48

having access to enough safe, healthy food at al times

Question 49

Where is food security an issue in?

Answer 49

Very poor countries Countries in conflict Can become a problem everywhere due to exponential growth of human population.

Question 50

how can we improve food security?

Answer 50

Agricultural methods More productive varieties of plants + animals

Question 51

What can climate change cause if temps are continuously increasing?

Answer 51

Can cause pathogens in new areas while non resistant crops and animals can be easily infected. Pathogens survive in warmer temperatures. eg. blue tongue virus. Flooding + drought impacts crop growing + land for meat production

Question 52

What are some solutions to decrease climate change? Why is growing plants for biofuel good to replace fossil fuels?

Answer 52

Reduce carbon emissions. We can grow plants for biofuel to replace fossil fuels. Biofuels are carbon neutral so the carbon released by burning a biofuel is only the amount removed from the air as the crops grow. (photosynthesis)