Topic 4: Starch and sustainability

Question 1

Define sustainability
(2 points - 1 general definition, 1 definition in terms of resources for humans)

Answer 1

1. The ability to MAINTAIN A BALANCE OF A PROCESS in a system
2. Using resources to meet the needs of the present generation, whilst preserving resources for future generations.

Question 2

How can humans be sustainable with their materials?

2 points

Answer 2

1. use RENEWABLE RESOURCES of materials

2. use materials and methods which MINIMISE HARM TO {BIODIVERSITY / THE ENVIRONMENT}.

Question 3

For humans to live sustainably, the Earth’s resources must be replenished at the ____ ____ at which they are used.

Answer 3

same rate

Question 4

Define sustainable
(2 points)

Answer 4

A resources that can be renewed,

so will not run out and is therefore available for future generations.

Question 5

Define biodegradable
(2 points)

Answer 5

Something that:

1. Will decompose and not accumulate
2. Will not contribute to landfill

Question 6

Define ecological footprint

1 point

Answer 6

The area of land you would require to support your current lifestyle.

Question 7

List 5 human activities that have negative impacts

any 5 from the list

Answer 7

Deforestation
 Pollution
 Over-hunting/fishing
 Illegal pet trade
 Ozone depletion
 Global warming
 Wasting electricity
 Replacing working products eg. mobile phones, TVs
 Over-use of cars

Question 8

List 5 human activities that have positive impacts

any 5 from the list

Answer 8

Recycling waste, clothes etc
Reusing/upcycling
Make do and mend
Tree planting and habitat regeneration
Quotas/bans (eg. on whaling)
Conservation initiatives
Banning CFCs
Fair trade products and ethical purchasing
Waking, cycling, car sharing

Question 9

List 5 things an individual could do to help the environment

any 5 from the list

Answer 9

Recycle old clothes and buy from charity shops

Cycle, walk or take {bus/train} – rather than driving

Don’t replace electronic devices (eg. mobile phones) that work, just to get the ‘latest model’

Buy a refillable {water bottle/coffee cup} to reuse

Recycle plastics and drinks cans

Don’t buy so much food, that a lot gets wasted

Buy fair trade chocolate, coffee etc.

Eat sustainable fish

Don’t use plastic bags, food bags etc.

Question 10

Key Summary: Why are products made from crude oil/plastic OR petrol/diesel (from crude oil) not sustainable?
(5 points)

Answer 10

1. Crude oil is a FOSSIL FUEL, so is non-renewable OR {plastic/petrol/diesel} COMES FROM crude oil which is a fossil fuel, so is NON-RENEWABLE
2. Crude oil WILL RUN OUT, so will NOT BE AVAILABLE FOR FUTURE GENERATIONS
3. Burning fossil fuels releases CO2 which contributes to Global Warming
4. Plastics may BIODEGRADE, decompose MORE SLOWLY – so will CONTRIBUTE TO LANDFILL
5. Plastics made from crude oil generate NON-BIODEGRADABLE WASTE

Question 11

Explain how the use of plant-based products can contribute to sustainability (3 points)

Examples of plant-based products: plant based plastics, starch bags, canvas bags, biodiesel

Answer 11

1. LESS FOSSIL FUELS are used up, so will last longer/be available for future generations
2. {Crops/trees/plants} CAN BE RE-GROWN – they are RENEWABLE to maintain supply for future generations
3. Plant based products are BIODEGRADABLE (decomposed by microbes) so don’t contribute to landfill

Question 12

Key Summary: Explain why a product made from starch/plants/jute fibres/bioplastic is sustainable
(3 points)

Answer 12

1. Made from plants OR comes from PLANTS - which are a renewable resource which will not run out
2. More PLANTS can be grown to REPLACE THOSE USED, so will be available for future generations
3. Biodegrade, decompose MORE QUICKLY – so will not contribute to landfill

Question 13

Plant fibres can be added to other materials to form ______________.

What are the advantages of ______________? (3 advantages)

NOTE: both “______________” are the same

Answer 13

biocomposites

eg. oilseed rape fibres and plastic are combined to make a material stronger than plastic alone
1. Renewable
2. More biodegradable
3. Easier and safer to handle than artificial composites

Question 14

Mats of plant fibres ABSORB _______ _______ and ____________ from polluted water
What is the advantage of this?
(1 advantage)

Answer 14

heavy metals

hydrocarbons

1. Avoids the use of chemicals

Question 15

Plant-based plastics or bio-plastics have been developed using renewable plant biomass sources from the __________ of sugars from wheat, sugar beet, potatoes, vegetable fats, corn starch, pea starch or agricultural waste.

Answer 15

fermentation

Question 16

How can plastic bags be replaced?

2 points

Answer 16

1. Use bags made of canvas, cotton, linen or jute that can be reused
   and are biodegradable at the end of their life
2. Use bags made of plant based plastic

Question 17

How can plastic packaging be replaced?

2 points

Answer 17

1. Buy loose fruit and veg at the supermarket and
   take your own reusable bags to put fruit and veg in
2. Take containers to put meat and fish in from the {counter/butcher}

Question 18

Carbohydrate polymers (starch) and oils from seeds have many important industrial uses.
List them
(5 uses)

Answer 18

1. Thickening
2. Stiffening
3. Super absorbents
4. Starch foam
5. Starch based plastics

Question 19

Starch is easily extracted – starch granules do not _______ in water and can be washed out of seeds

Answer 19

dissolve

Question 20

Explain “Thickening” of starch

3 points

Answer 20

1. Heating starch granules in water,
2. they swell, absorb water, and thicken liquid.
3. This is called ‘gelatinisation’

Question 21

Explain “Stiffening” of starch

5 points

Answer 21

1. Starch mixture is applied to {fabric/paper},
2. then gelatinised,
3. then cooled.
4. Bonds form between starch molecules
5. This is called “sizing”.

Question 22

How can the stiffening of starch be reversed? (1 point)

What is this process called? (1 point)

Answer 22

1. By adding water (the material becomes flexible again)

2. Plasticisation

Question 23

Explain how “Super Absorbents” made from starch

4 points

Answer 23

1. Starch is chemically cross-linked,
2. then gelatinised.
3. This forms particles which are dried.
4. Particles can absorb large amounts of water.
   e. g. Cross-linked starch is found in super-absorbent nappies

Question 24

Explain how “Starch foam” is made from starch

4 points

Answer 24

1. Starch granule containing very little water is put under pressure in a starch extruder, which is a machine that applies pressure,
2. heating takes place and pressure builds up.
3. Pressure is suddenly released (eg. seed coat ruptures during cooking to make popcorn).
4. Steam forms, so starch ‘puffs’ into an expanded structure.

NOTE: Starch foam is used in pop corn, packing foam, puffed cereals etc…

Question 25

Seeds are a rich source of ____ used for cooking and also ____. ________ can be used in unmodified diesel engines alternating with petroleum diesel (produces less ________ _______ and ________ _______ than diesel).

Answer 25

oils fuel Biodiesel sulphur dioxide carbon dioxide

Question 26

What can biodiesel be made from? (2 things)

Answer 26

1. Waste vegetable cooking oil | 2. Oil crops (e.g. rapeseed oil)

Question 27

Give 3 examples of what starch is used in | any 3 from the list

Answer 27

custard powder, wallpaper paste, nappies, packaging foam, adhesives, paints, textiles, plaster, insulation, toiletries i.e. shampoo, mousses, sunscreens & anti-perspirants

Question 28

Give 2 examples of what oils are used in | 2 examples

Answer 28

1. Cooking oil (e.g. sunflower oil) | 2. biofuels

Question 29

In terms of sustainability, what needs to be considered about plant based products? (2 things)

Answer 29

1. the SOURCE of the plant product and whether land has been cleared of trees to be used for growing the plant crop e. g. reduced biodiversity due to palm oil plantations for biodiesel 2. the {ENERGY/FUEL} USED and POLLUTION created during PRODUCTION and TRANSPORT of product

Question 30

What should be considered about a sustainable resource to determine its advantages and disadvantages? (7 points) NOTE: Do not list adv/disadv. just list what needs to be considered.

Answer 30

1. {How carbon neutral it is/how well crop removes carbon dioxide from atmosphere (by photosynthesis) as plant grows} + link to {greenhouse effect / global warming} 2. How much {water/fertilisers/pesticides} the crop requires and effect of fertilisers on the ecosystem 3. Which fuel is used to transport the {crop/resource} 4. What else the land could be used for? eg. food production 5. The low biodiversity of a monoculture 6. {Production costs/support for the economy} 7. Does it provide jobs for local people?

Question 31

What are the key terms that should be used when answering a question about {sustainability/a sustainable product} (8 points)

Answer 31

1. Sustainable (if not mentioned in the question) 2. From a RENEWABLE RESOUCE (eg. plant), so WILL NOT RUN OUT, so AVAILABLE FOR FUTURE GENERATIONS (often compared to products from crude oil which is a non-renewable resource) 3. MORE PLANTS CAN BE GROWN to replace those used 4. BIODEGRADABLE – so will DECOMPOSE and NOT CONTRIBUTE TO LANDFILL 5. COST – plant products may be cheaper 6. STRENGTH – plant products e.g. jute ropes, may not be as strong as plastic/synthetic ones 7. Using plant products will allow crude oil supplies to last longer 8. Time scale – plants can be grown quickly, fossil fuels/crude oil takes millions of years to form (NOTE: when answering a question, choose the most appropriate points)