L3: Exploiting plant metabolism (EXTRA)

Question 1

Describe the development of ethanol fuel use in Brazil

Answer 1

Established in 1970
- Developed due to increase petrol prices, Brazil being unable to import petrol or produce own oil
- Furthered by Flex fuel vehicles that can run on both ethanol and petrol (also containing ethanol)
- Ethanol is derived from sugarcane fermentation that converts sucrose

Question 2

What are some effects of sugar cane growth on Brazil?

Answer 2

• 1% of land taken up, 4% of agricultural land
• Grown in the south away from the Amazon so doesn’t lead to direct deforestation of the forest
• Farmers can choose what to do with the sucrose from sugar cane, either keep as sugar for Coca Cola or ferment to make ethanol

Question 3

Describe the development of ethanol fuel use in USA

Answer 3

15% of transport fuel by ethanol derived from Maize (fermentation of glucose)
- no flex fuel cars so unlikely that this will increase
- large government subsidies in the past
Negatives: competes with production of Maize as a food source

Question 4

Describe the energy and C inputs and outputs of growing maize for fuel production

Answer 4

C
- Plants take up CO2, but emissions from transport and machinery associated with growth
Energy
- intensive farming require fertiliser and pesticides which require energy for production
- Distillation and fermentation process requiring energy that is derive from fossil fuels