food production Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

what conditions can be manipulated in a glasshouse

A

Artificial heating (enzymes controlling photosynthesis can work faster at slightly higher temperatures - only used in temperate countries such as the UK)
Artificial lighting (plants can photosynthesise for longer)
Increasing carbon dioxide content of the air inside (plants can photosynthesise quicker)
Regular watering

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what farmers in tropical countries may consider to manipulate?

A

need to be ventilated to release hot air and avoid temperatures rising too high, which could cause the denaturation of the enzymes controlling the photosynthesis reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

polyethene tubes

A

large plastic tunnels that cover crops

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

polythunels uses

A

They can protect crops grown outside from the effects of the weather, including excessive wind, rain and extreme temperatures
They also increase the temperature slightly inside the tunnel
They can prevent the entry of pests that can damage plants or diseases that can kill plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

3 limiting factors of photosynthesis

A

Temperature
Light intensity
Carbon dioxide concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

how does temperature affect the rate of photosynthesis

A

.temperature increases the rate of photosynthesis
.this is only to a certain point as enzymes begin denature and the rate of reaction decreases.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how does light affect the rate of photosynthesis

A

more light, faster rate of photosynthesis
This trend will continue until some other factor required for photosynthesis prevents the rate from increasing further because it is now in short supply

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how does carbon dioxide affect the rate of photosynthesis

A

.more carbon dioxide faster rate of photosynthesis
.This trend will continue until some other factor required for photosynthesis prevents the rate from increasing further because it is now in short supply

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

fertilisers

A

increase the amount of key nutrients in the soil for crop plants, therefore plants can grow more larger and healthy which increases crop yield

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

pesticides

A

these chemicals kill off unwanted insects and weed species, meaning that there is less damage done to crop plants by insects, as well as reducing competition from other plant species, which increases yields

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

organic fertilisers

A

manure and compost

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

chemical fertilisers

A

dry granules or can be sprayed on in liquid form
They mainly provide crop plants with nitrogen, phosphorus and potassium:

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

nitrogen in fertilisers

A

Absorbed in the form of nitrates
Needed to make amino acids which are the building blocks of proteins
Lack of nitrogen causes weak growth and yellowing of the leaves of plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

potassium in chemical fertilisers

A

Absorbed in the form of various compounds of potassium
Allows enzyme reactions to take place to produce ATP in respiration as well as being needed for the enzymes involved in photosynthesis
Lack of potassium can cause poor growth of flowers and fruits, as well as brown spots on leaves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

phosphorus in fertilisers

A

Absorbed in the form of phosphates
Needed to make DNA and cell membranes
Lack of phosphorus can cause poor root growth and discoloured leaves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

types of pesticides

A

Insecticides kill insect pests
Herbicides kill plant pests
Fungicides kill fungal pests

17
Q

advantages of pesticides

A

easily accesible
immediate effect
kills entire population of pests

18
Q

disatvantages of pesticides

A

organisms can develop resistance
can kill beneficial organisms as they are non specific
do not break down
need to be repeatedly applied

19
Q

advantages of biological control

A

no pollution
no resistance
can target specific species
long lasting
does not need to be repeatedly applied

20
Q

disatvantages of biologocal control

A

may eat other organisms instead of pests
takes longer to be effective
cannot kill entire population
may not to new environment or may move out of area
may become a pest itself

21
Q

bread making steps

A

Yeast will respire anaerobically if it has access to plenty of sugar, even if oxygen is available
This is taken advantage of in bread making, where the yeast is mixed with flour and water
The yeast produces enzymes that break down the starch in the flour, releasing sugars that can then be used by the yeast for anaerobic respiration
The carbon dioxide produced by the yeast during anaerobic respiration is trapped in small air-pockets in the dough, causing the dough to rise (increase in volume)
The dough is then baked in a hot oven to form bread
During baking, any ethanol produced by the yeast (as a waste product of anaerobic respiration) is evaporated in the heat
This is why bread doesn’t contain any alcohol
The yeast is killed by the high temperatures used during baking
This ensures there is no further respiration by the yeast
Once cooled, the bread is ready to be eaten

22
Q

anaerobic respiration formula

A

glucose = ethanol and carbon dioxide
C6H12O6 = 2C2H5OH and 2CO2

23
Q

why are bacteria useful in yogurt production?

A

.capable of producing complex molecules
.reproduce rapidly

24
Q

how to calculate dry mass

A

pass content through filter paper
heat filter paper
wight

25
Q

why are plants selectively bred?

A

Disease resistance in food crops
Increased crop yield
Hardiness to weather conditions (eg. drought tolerance)
Better tasting fruits
Large or unusual flowers

26
Q

what can selective breeding lead to?

A

it can lead to inbreeding

27
Q

what does inbreeding result in?

A

This results in a reduction in the gene pool – this is a reduction in the number of alleles (different versions of genes) in a population
As inbreeding limits the size of the gene pool, there is an increased chance of:
Organisms inheriting harmful genetic defects
Organisms being vulnerable to new diseases (there is less chance of resistant alleles being present in the reduced gene pool)