Topic 7 - Biodiversity + Trophic Levels + Food

Question 1

What is biodiversity?

Answer 1

Biodiversity is the variety of all the different species on earth or within and ecosystem.

Question 2

What is there if there is a high level of biodiversity?

Answer 2

There is a variety of different species, also known as a ‘stable ecosystem’

Question 3

Why is a ‘stable ecosystem’ important? (Provide an example as well.)

Answer 3

Because it means that they are less dependent on other species. For example, if the number of dogs fall in an ecosystem it should have little effect on the different species.

Question 4

Explain how humans are having a negative effect on biodiversity.

Answer 4

Tropical rainforests are rich in biodiversity but they are being destroyed for land.

Question 5

What is the land being used for once its broken down in a tropical rainforest?

Answer 5

It is used for rice fields or grazing cattle. Crops are also grown which we use for biofuels.

Question 6

What is an effect of an increase in population (NOT food security wise)

Answer 6

Increase in pollution levels.

Question 7

How are toxic chemicals being released in the river affect biodiversity?

Answer 7

Toxic chemical are released in the river, which kills animals.

Question 8

How do fertilisers affect water pollution?

Answer 8

Fertilisers cause dissolved oxygen levels to fall, which kills aquatic organisms.

Question 9

How does sewage in water affect biodiversity?

Answer 9

Sewage contains urine and faeces, some countries it is released, in the UK its treated. However, this can accidentally glow in the river/stream.

Which causes dissolved oxygen levels to fall killing aquatic organisms.

Question 10

How does polluting the air reduce biodiversity?

Answer 10

Burning coal in power stations can release acidic gases, which cause acid rain and smoke. Both of these can kill plants and animals which reduce biodiversity.

Question 11

How does polluting the land reduce biodiversity?

Answer 11

The waste is dumped in landfills, which is destroying habitats, toxic chemicals are polluting the soil or are just being dumped directly onto land.

So this reduces biodiversity as animals are killed/habitat lost.

Question 12

What do humans use land for?

Answer 12

They use it for building, for example houses, airports, factories and most importantly, farms and quarries.

Question 13

How does building new land reduce biodiversity?

Answer 13

There is less land available for animals and plants, as habitats are destroyed and destructed.

Question 14

Why is dumping waste in landfills an issue? (in terms of land use)

Answer 14

They take up a lot of space, and destroy natural habitat most of the time which reduces biodiversity.

Question 15

What do peat bogs contain? What are the conditions in them?

Answer 15

They contain dead plant materials, the conditions of them cause decay to be slow.

Contain a large amount of trapped carbon.

Question 16

What are peat bogs used for?

Answer 16

Used for cheap compost, and burnt for electricity.

Question 17

How does the destruction of peat bogs reduce biodiversity?

Answer 17

They firstly destroy habitat.
When peat is burned, it releases carbon dioxide into the atmosphere which contributes to climate change.

Question 18

What are farmers doing to prevent peat bogs being destroyed? Why is there no simple answer?

Answer 18

They stop buying this as it affects biodiversity. However, the alternatives are more expensive, so price of food goes up, hence there is no simple answer.

Question 19

What are the causes of global warming? (2)

Answer 19

Burning of fossil fuels which release carbon dioxide. Levels of methane increased which is produced in payday fields and cows.

Question 20

Why is the media an issue with global warming?

Answer 20

Their work is not peer reviewed so their ideas about global warming can be oversimplified, inaccurate or biased.

Question 21

What are some of the consequences of global warming? (Explain them.)

Answer 21

1. Ocean temperatures increasing causing melting of ice caps, so artic animal population reduces.
2. Animals are extending their range Northwoods due to cooler conditions, they could bring diseases with them.
3. Many species migrate, as global warming causes these patterns to change.
4. Plants in the UK are flowering early due to warmer conditions, now new crops can grow in the UK, but others it may be to much.

Question 22

What are breeding programmes? How do they maintain biodiversity?

Answer 22

They are for endangered species where other zoos lend their endangered animals to others as they can breed together. Which allows for extinct species to grow - reducing biodiversity.

Question 23

What are the protection and regeneration of habitats? How do they maintain biodiversity.

Answer 23

Protection and regeneration of habitats ensure that areas which are rich in biodiversity are kept eg wetlands. So protection and regeneration of rare habitats help preserve biodiversity.

Question 24

How do farmers try to prevent biodiversity?

Answer 24

Farmers leave strips of land around fields where plants/animals live known as field margins.

They also plant hedgerows between fields, where lots of different species live, so they preserve biodiversity on farms.

Question 25

How are governments trying to maintain biodiversity?

Answer 25

1. Taken steps to reduce deforestation, e.g National Parks. 2. Taking action to reduce carbon dioxide emissions, changing to renewable electricity. All this prevents the reduction of biodiversity.

Question 26

How can individuals maintain biodiversity?

Answer 26

They can recycle materials so less waste ends up in landfill, so less habitat destroyed having a positive effect on biodiversity.

Question 27

What are the reasons behind deforestation?

Answer 27

1. Clear land for farming and raising cattle and crops, also to create biofuels. 2. To get wood known as 'logging' where they use it or burn it for fuels.

Question 28

What are the problems behind deforestation?

Answer 28

1. No trees for photosynthesis, will not be taking in the carbon dioxide. 2. When burnt, they release all the carbon they were holding and release smoke which can suffocate animals. 3. Destruction of habitat, reduces biodiversity, some species may even go extinct.

Question 29

What are the positions of the food chains considered as? What is the definition of that?

Answer 29

They are considered trophic levels, trophic in terms of 'feeding'

Question 30

What are the different trophic levels?

Answer 30

Producers are trophic level 1, primary consumers is trophic level 2, and so on.

Question 31

What are decomposers? How do they work?

Answer 31

They break down dead plants and waste producers. Which returns mineral ions to the soil. They secrete enzymes into environment, the enzymes 'digest' dead materials. The food molecules diffuse back into the decomposer.

Question 32

What is biomass?

Answer 32

Biomass is the living tissue of an organism, makes up the mass of the organism.

Question 33

When we measure the biomass, is it dry mass or wet mass?

Answer 33

It will be the dry biomass as the moisture content of organisms can vary slightly.

Question 34

What does a pyramid of biomass represent?

Answer 34

It represents the food chain in a bar chart/pyramid shape, it highlights the amount of biomass decreasing.

Question 35

Why does the amount of biomass decrease when you go up the trophic levels? (3)

Answer 35

1. Not all materials that the bird ingests is absorbed, some is ejected as faeces. 2. Some of the biomass absorbed is converted into waste products of metabolism and is released. 3. Large amount of biomass is used in respiration.

Question 36

How do animals/plants respiring cause a decrease in biomass?

Answer 36

Respiration releases energy which is used for movement/constant body temperature. It also produces Carbon Dioxide and water, and some of the biomass is used to produce these waste compounds.

Question 37

How do we calculate the efficiency of biomass transfer? (State the equation)

Answer 37

Gain in Biomass/Total Biomass intake is equal to efficiency.

Question 38

How much biomass tends to be passed on to each trophic level.

Answer 38

Only around 10 percent.

Question 39

What is food security?

Answer 39

Food security is hving enough food to feed a population.

Question 40

Why is food security important?

Answer 40

As many people live in cities - so it is more difficult for them to grow their own crops.

Question 41

What are the six factors threatening food security? (Do NOT explain them)

Answer 41

1. Birth Rate 2. Taste Change 3. Pests and Pathogens 4. Environmental Change 5. Conflict 6. Farming

Question 42

How do the 3 factors listed below affect food security? (Birth Rate, Taste change, Pathogens)

Answer 42

1. Birth Rate increasing as population grows so will the amount of food needed to feed the population. 2. Taste is changing, we expect a range of different foods, many of this has to be imported in the UK from other countries - threatening their food security. 3. Pests eat food crops, pathogens cause infectious diseases, so this will remove these crops from production.

Question 43

How do the three factors listed below threaten our food security? (Environmental Change, Farming and Conflict.)

Answer 43

1. Their is unpredictable weather change, e.g rain patterns, so countries may not be able to grow their own crops leading to famine. 2. Farming takes a great deal of resources, fertilisers and pesticides increase yield, live stock need food, resources are becoming more expensive. Some countries cannot afford this, threatening their food security. 3. During conflict like war, farming is disrupted, import of foods are not available, and it threatens a reliable source of water.

Question 44

Why should sustainable methods be found to feed people as population increases?

Answer 44

So our long term food security can be increased. We need to overcome food shortages.

Question 45

What does sustainable food methods involve doing?

Answer 45

Making enough food without using up resources faster than these resources can be made.

Question 46

What are the two ways the efficiency of food production can be improved? Explain how.

Answer 46

1. Limiting their movement - livestock are kept in small pens or cages so they move around less, restricting energy transfer. 2. Controlling temperature of surroundings - They require less energy for them to return to optimum body temp.

Question 47

What are some animals fed to increase growth in intensive farming?

Answer 47

High Protein Diets.

Question 48

What are some of the ethical concerns of intensive farming?

Answer 48

Animals should be raised in natural conditions, and with normal behaviour to increase animal welfare.

Question 49

What are the advantages of intensive farming?

Answer 49

More efficient as less biomass is wasted, we can control food for optimum yield, and eggs can be more easily harvested.

Question 50

What are the disadvantages of intensive farming?

Answer 50

Infectious diseases spread, they can be treated with antibiotics, but it can increase antibiotic resistance, more stressed in the conditions, tend to fight. Ethical concerns as well.

Question 51

What is happening to fish stocks in the ocean and why?

Answer 51

They are declining as there is an increase in huge trawler ships which have huge nets and modern technology, also overfishing.

Question 52

What are the problems with overfishing?

Answer 52

When fish stocks fall below a certain level, their is not enough to reed, so fish stocks collapse disrupting food chains, humans having less fish to eat, as well as some fish disappearing from areas.

Question 53

What are the two ways the governments are attempting to reverse overfishing (Do NOT explain)

Answer 53

1. Fishing Quotas. 2. Size of net.

Question 54

How are fishing quotas preventing overfishing?

Answer 54

If there is a limit of the number of fish that can be caught, the remaining fish can breed and bring the population back to a normal level.

Question 55

How are controlling net size reverting overfishing?

Answer 55

Net sizes must be large enough for immature fish to breed, they can develop into an adult and not get caught when young so they can breed and return the population back to normal.

Question 56

What do modern biotechnology involve and why?

Answer 56

c

Question 57

How is mycoprotein produced from a fungus? (5)

Answer 57

1. Fusarium is cultured in fermenters. 2. The fermenters have optimum conditions for the fusarium to grow. 3. It grows in aerobic conditions and provided with glucose syrup so it can respire. 4. Fungus grows and multiplies within the fermenter 5. It is collected and purified to create mycoprotein.

Question 58

What are the advantages of mycoprotein?

Answer 58

1. Suitable for vegetarians and have a rich protein source. 2. Can grow a large amount in limited space - making it efficient.

Question 59

'People only rely on rice in some countries' what does this cause and why?

Answer 59

It can cause blindness as they are Vitamin A deficient. Because the body makes the vitamin from the molecules in the food - which the rice does not have.

Question 60

What is golden rice? What could it prevent?

Answer 60

Golden rice is genetically modified rice which contains the molecules for Vitamin A to be made in the body - which could prevent people going blind from the deficiency.