3.5 food profuction

Question 1

human population and food demand

Answer 1

the ever increasing human population requires the ever increasing production to meet the ever increasing food demand that results from a human population

Question 2

two groups of chemicals to increase food production

Answer 2

pesticides
fertilisers

Question 3

how can fertilisers increase crop yield

Answer 3

fertilisers contain chemical nitrate nitrate increase crop yield as the plan absorbed the nitrate in the soil it uses it for amino acids which makes protein synthesis proteins are then vital components of cells which are essential for cell division and growth

Question 4

how pesticides grow crop yield

Answer 4

pesticides are used to kill plants and animals that reduce crop yield. if pesticides are used to kill catipillar a it will increase crop yeold as the leads will not be eating and damages and their will be a greater surface area for photosynthesis

Question 5

nitrogen cycle

Answer 5

nitrogen in the soil is in the form nitrate which dissolved into soil water. nitrate is absorbed by plant roots which then they use for amino acids and synthesis plant protein which is used for plant growth. The plant proteins are eating by animals and the plant protein is broken down to amino acids during digestion in the animals body and then converted into animal protein during animal growth. Urine and faeses released by animals along with dead animals and animal bodies can contain proteins. These will be produced through the actions of fungal and bacteria to release nitrogen they contain forms of nitrate. These nitrates will dissolve back into soil and then the process starts again

Question 6

adding fertilised to nitrogen cycle

Answer 6

this will increase nitrate so more plants can absorb and make amino acids for protein synthesis which will then increase plant growth

Question 7

extra fertilisers

Answer 7

thsi will cause algal bloom as there is too much nitrate which will then grow plants in water wchich will then increase algal population

Question 8

GM crops to reduce fertilisers

Answer 8

genetically modified variations of plants can be made whe their is a low concentration of nitrate in soil reducing need for fertilisers

Question 9

role of GM reducing use of pesticides

Answer 9

genetically modified plants are made in variations to stop certain insects from eating or damaging the plant which are toxic to insects when they eat. the variations will not be eating by insects so then pesticides are not needed

Question 10

algal bloom

Answer 10

excess nitrate in water
algal bloom spears
blocks sunlight from getting into the other water plants
water plants die as they can no long photosynthesise
dead plant material good food source for bacteria
bacteria population increases
bacteria uses all oxygen for respiration
all other organisms living in the ecosystem will die as for lack of oxygen

Question 11

biocumulation

Answer 11

build up of toxic substances in food chain

Question 12

consequences of biocumulation

Answer 12

result in toxic concentrations as the toxin is passed through food chain
concentration of toxin increases at each trophies level it can reach lethal levels of toxity causing death of organisms

Question 13

biological control

Answer 13

the use of one species to control the population of another species. The species used for biological control are predators or parasite of the species being controlled.

Question 14

advantages of biological control rather than pesticides

Answer 14

reduces chemical in environments so reducing problems such as biocumulation and toxicity