3.5: Food Production Flashcards
What is the effect of the human population increasing?
More food needs to be produced from the same area of land
What are the methods of increasing food yields?
2
- Fertilisers
- GM Crops
What are the methods for preventing pests damaging crops?
3
- Pesticides
- GM Crops
- Biological control
What is an advantage & disadvantage of fertiliser?
- A: Increases crop yield
- D: Can leach into fresh water
What is an advantage & disadvantage of pesticides?
- A: Prevents crop damage
- D: Bioaccumulation in food chains
What is an advantage & disadvantage of GM crops?
- A: Can increase yields and protect from pests
- D: Expensive
What is an advantage & disadvantage of biological control?
- A: No chemicals required
- D: Difficult to manage
What are nitrates?
Chemical which increases crop yield by producing amino acids for plant proteins
How do fertilisers help plants grow?
4
- Added to the soil to increase nitrate content
- Nitrates dissolve in water and are absorbed by plants
- Nitrates used to make amino acids which are combined to make plant proteins
- Animals eat plants or other animals to obtain amino acids for protein synthesis
What is an algal bloom?
5
- Fertilisers leach into water
- There is an increase in algal populations
- Algal blooms reduce light levels, killing aquatic plants
- Dead plants become food for bacteria, which increase in numbers
- Bacteria use up oxygen which kills the fish
What are pesticides?
Chemicals used to kill pests and prevent damage to crops
What is bioaccumulation?
When pesticides accumulate in the bodies of organisms who consume crops, and this is passed along food chains which increases toxicity
What are GM crops?
Crops with new genes to give them improved characteristics (e.g: larger yields, better pest resistance)
What is biological pest control?
The use of animals to control pests in an area
