Key Area 5: Food Production

Question 1

Food yield

Answer 1

Increasing human populationrequires increased food yield. This can involve the use of fertilsers and pesticides.

Question 2

Fertilisers

Answer 2

Provide chemicals such as nitrates which increase crop yield.

Question 3

Pesticides

Answer 3

Plants and animals which reduce crop yield are killed by pesticides.

Question 4

Nitrates

Answer 4

dissolved in soil water are absorbed into plants

Question 5

Amino acids

Answer 5

Nitrates are used to produce amino acids

Question 6

Proteins

Answer 6

Amino acids are synthesised into plant proteins

Question 7

Soil nitrates

Answer 7

Fertilisers can be added to soil to increase the nitrate content of soil

Question 8

Leaching

Answer 8

Fertilisers can leach into fresh water adding extra unwanted nitrates.

Question 9

Algal blooms

Answer 9

Leaching will increase algal populations which can cause algal blooms

Question 10

What does algal bloom do?

Answer 10

Reduces light levels
Kills aquatic animals

Question 11

Bacteria

Answer 11

The dead plants, as well as dead algae become food for the bacteria which increases greatly in number

Question 12

Oxygen

Answer 12

The bacteria use up large quantities of oxygen, reducing the oxygen availability for other organisms

Question 13

Genetically Modified (GM) Crops

Answer 13

May be grown to reduce the use of fertilisers

Question 14

Bioaccumulation

Answer 14

Pesticides sprayed onto crops can accumulate in the bodies of organisms over time

Question 15

Toxicity

Answer 15

As pesticides are passed along food chains toxicity increases and can reach lethal levels

Question 16

Biological control

Answer 16

is an alternative to the use of pesticides. This is the use of natural predators, parasites or disease organisms to control pests on field crops and glasshouses.