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ecology Flashcards

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Biology 101 flashcards
1
Q

define an ecosystem

A

the interaction of a community of living (biotic) organisms with the non-living (abiotic) parts of their environment

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2
Q

what do organisms need to survive and reproduce

A

a supply of materials from their surroundings and from the other living organisms there

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3
Q

what do plants in a community or habitat often compete for

A

they often compete with each other for light and space, and for water and mineral ions from the soil

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4
Q

what do animals in a community or habitat often compete for

A

they often compete with each other for food, mates and territory

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5
Q

define a stable community

A

one where all the species and environmental factors are in balance so that population sizes remain fairly constant

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6
Q

define interdependence

A

within a community each species depends on other species for food, shelter, pollination, seed dispersal, etc. if one species is removed it can affect the whole community

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7
Q

list the abiotic factors which can affect a community

A
  • light intensity
  • temperature
  • moisture levels
  • soil pH and mineral content
  • wind intensity and direction
  • carbon dioxide levels for plants
  • oxygen levels for aquatic animals
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8
Q

define habitat

A

the place where an organism lives

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9
Q

define a population

A

the total number of organisms of the same species living in the same geographical area

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10
Q

define a community

A

the populations of all the different species that live in the same habitat

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11
Q

how does increasing temperature affect a community and what factor is it

A

temperature = abiotic factor

it could cause the distribution of species to change - animals may migrate to cooler areas and plants may die due to high rates of transpiration

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12
Q

how does lack of light intensity affect a community and what factor is it

A

light intensity = abiotic factor

it’s needed for photosynthesis, so lack thereof could lead to decreased plant populations, leading to decreased food for animals

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13
Q

how does soil pH and mineral content affect a community and what factor is it

A

soil pH and mineral content = abiotic factor

plants cannot grow on soils too acidic or too alkaline, and they also need certain mineral ions in the soil

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14
Q

how do moisture levels affect a community and what factor is it

A

moisture level = abiotic factor

all organisms require water to survive

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15
Q

how does wind intensity affect a community and what factor is it

A

wind intensity = abiotic factor

can affect transpiration in plants

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16
Q

how do decreasing carbon dioxide levels affect a community and what factor is it

A

carbon dioxide levels = abiotic factor

it’s needed for photosynthesis, so lack thereof could lead to decreased plant populations, leading to decreased food for animals

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17
Q

how do oxygen levels affect a community of aquatic animals and what factor is it

A

oxygen levels = abiotic factor

oxygen is required for aerobic respiration. the level of oxygen in the air remains fairly constant, but dissolved oxygen levels are liable to fall on hot days, which can be dangerous for aquatic animals e.g., fish

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18
Q

list the biotic factors which can affect a community

A
  • availability of food
  • new predators arriving
  • new pathogens
  • one species outcompeting another so the numbers are no longer sufficient to breed
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19
Q

how does availability of food affect a community of aquatic animals and what factor is it

A

availability of food = biotic factor

all animals eat other living organisms - all sources of food are a biotic factor. if the availability of food decreases, then the number of organisms in the community will also fall

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20
Q

how does the arrival of new predators affect a community of aquatic animals and what factor is it

A

new predators arriving = biotic factor

this can cause the population or prey species to fall. it could also affect existing predators if they are competing for the same prey

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21
Q

how do new pathogens affect a community of aquatic animals and what factor is it

A

new pathogens = biotic factor

if a new disease emerges and spreads, it can wipe out a population of species

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22
Q

how does one species outcompeting another affect a community of aquatic animals and what factor is it

A

if a species is outcompeted, the numbers can decrease to the degree that the numbers are no longer sufficient for breeding and the species becomes extinct

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23
Q

define an adaptation

A

any feature that enables an organism to be a better competitor and be more likely to survive and reproduce within their environment

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24
Q

what can adaptations be + give examples

A

structural - i.e. physical features, e.g., camouflage
functional - how the body operates, e.g., sweating
behavioural - how the organism acts, e.g., hibernation

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25
Q

common adaptations for animals in cold climates

A
  • thick fur coats
  • layers of blubber under the skin
  • fat, round body shapes with short legs (smaller SA:V ratio)
  • small ears
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26
Q

common adaptations for animals in hot climates

A
  • large thin ears
  • little body fat
  • thin fur
  • long limbs to increase SA:V ratio
  • long eyelashes
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27
Q

define extremophiles

A

organisms that live in very extreme environments, such as at high temperatures, pressures, or salt concentrations

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28
Q

state an example of an extremophile

A

bacteria living in deep sea vents

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29
Q

what are photosynthetic organisms

A

the producers of biomass for life on earth

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30
Q

what do all food chains begin with

A

producers - usually a green plant or alga

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31
Q

why are producers important in food chains

A

they synthesise complex molecules using the sun’s energy in photosynthesis to make glucose, which is called biomass. plants effectively generate biomass so that consumers along the food chain can eat it and live

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32
Q

what do food chains represent

A

feeding relationships within a community

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33
Q

what do ecologists use transects and quadrats for

A

to determine the distribution and abundance of species in an ecosystem

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34
Q

order of producers to tertiary consumers

A

producers -> primary consumers -> secondary consumers -> tertiary consumers

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35
Q

define a predator

A

a consumer that kills and eats other animals

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36
Q

define prey

A

an animal that is eaten by other animals

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37
Q

what happens in a stable community in terms of prey and predators

A

the numbers of predators and prey rise and fall in cycles

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38
Q

define biodiversity

A

the variety of all the different species of organisms on earth, or within an ecosystem

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39
Q

how does a great biodiversity ensure the stability of ecosystems

A

it reduces the dependence of one species on another for things like food, shelter and the maintenance of the physical environment - hence makes ecosystems more stable

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40
Q

what does the future of the human species rely on

A

us maintaining a good level of biodiversity

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41
Q

why is biodiversity reducing

A

due to many human activities; only recently have measures been taken to try to stop this reduction

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42
Q

what do humans depend on biodiversity for

A

sustained food growth, clean air, water, medicine, shelter

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43
Q

what happens if populations increase or decrease in an ecosystem

A

nature tends to restore the balance over time to maintain biodiversity

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44
Q

what do different materials cycle through

A

the abiotic and biotic components of an ecosystem

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45
Q

why are all materials in the living world recycled

A

to provide the building blocks for future organisms

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46
Q

what is the function of the carbon cycle

A

it returns carbon from organisms to the atmosphere as carbon dioxide, which is to be used by plants in photosynthesis

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47
Q

what is the function of the water cycle

A

it provides fresh water for plants and animals on land before draining into the seas - water is continuously evaporated and precipitated

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48
Q

what is the only way that carbon can enter the carbon cycle

A

photosynthesis

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49
Q

how does carbon dioxide return back to the atmosphere in the carbon cycle

A

by aerobic respiration

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50
Q

what two key processes does the carbon cycle involve

A
  • photosynthesis; brings carbon into the cycle
  • respiration; returns carbon back into the atmosphere
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51
Q

carbon cycle steps

A
  • plants and algae take in carbon dioxide from atmosphere in photosynthesis
  • carbon used to make carbs, fats and proteins which make up cells of plants and algae
  • when they respire, some of carbon is released back to atmosphere as carbon dioxide
  • plants and algae eaten by animals which can be eaten by other animals
  • carbon that was in plants is now in animal cells
  • animals respire so some carbon released back to atmosphere as carbon dioxide
  • animals release waste products e.g., faeces, and all animals and plants die; releases carbon in waste products and in dead remains
  • waste products and dead remains broken down by decomposing microorganisms e.g., bacteria and fungi
  • when decomposers carry out respiration, carbon in the waste and dead remains returned to atmosphere as carbon dioxide
  • they also release mineral ions into the soil
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52
Q

why are decomposers important

A

they cycle materials through an ecosystem

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53
Q

why do decomposers sometimes not function effectively and what effect does this have on the carbon cycle

A

under certain conditions e.g., a lack of oxygen. if this happens, carbon in dead remains slowly converted to fossil fuels. humans combust these fossil fuels, releasing a large amount of carbon dioxide back into the atmosphere.

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54
Q

water cycle steps

A
  • energy from sun causes water to evaporate from surface of sea
  • water vapour travels into air and cools down
  • when it cools, water vapour condenses to form clouds
  • water in clouds falls to ground as precipitation (rain, snow, hail, sleet)
  • once it hits ground, some evaporates back into atmosphere as water vapour
  • some passes through rocks and forms aquifers
  • a lot of it forms river and streams, which eventually drains back into the sea
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55
Q

what do all forms of precipitation contain

A

fresh water - no salt

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56
Q

how do plants play a role in the water cycle

A

plants take up water in their roots; water moves up plant in xylem and passes out through stomata as water vapour (TRANSPIRATION)

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57
Q

how do animals play a role in the water cycle

A

animals take in water through food and drink. water released in urine, faeces and exhalation.

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58
Q

how does temperature affect the rate of decay of biological material

A

warmer temp = faster rate of decomposition as enzymes used by decomposers to break down plant materials are working faster as more kinetic energy. compost usually warm due to energy released by respiration from decomposers - compost must not get too hot or enzymes in decomposers could denature and decomposers could die.

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59
Q

how is compost made

A

gardeners put dead plant material (e.g., grass) onto compost heap. over time, bacteria and fungi decompose plant material and produce compost. they try to provide optimum conditions for rapid decay of waste biological material to produce the compost.

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60
Q

how is compost used

A

as a natural fertiliser for growing garden plants or crops - this works because compost is very rich in minerals needed by plants to grow

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61
Q

how does water affect the rate of decay of biological material

A

moister compost = faster rate of decomposition, as many chemical reactions involved in decay require water. gardeners must not allow compost heap to dry out.

62
Q

how does availability of oxygen affect the rate of decay of biological material

A

oxygen needed for decomposers to aerobically respire to release energy needed for decay.compost bins have holes in walls to allow oxygen to enter

63
Q

what is a gardening fork used for

A
  • to mix compost regularly to allow more oxygen to pass into the centre
  • to break up large clumps of compost which increases surface area for decomposers to act on
64
Q

what is produced by anaerobic decay and how can this be used

A

methane - biogas generators can be used to produce methane gas as a fuel for homes

65
Q

environmental changes that affect the distribution of species in an ecosystem

A
  • temperature (geographic)
  • availability of water (geographic)
  • composition of atmospheric gases (human interaction)

changes may be seasonal, geographic or caused by human interaction

seasonal -> migration, e.g., bats migrating south to spend winter in mexico where conditions are warmer

66
Q

what can changes in abiotic factors also effect

A

the distribution of species

67
Q

how does composition of atmospheric gases affect lichens

A

lichens extremely sensitive to sulfur dioxide produced by burning fossil fuels - therefore large numbers found where air is unpolluted

68
Q

how does composition of atmospheric gases affect levels of gases dissolved in water

A

if sewage is allowed into streams, oxygen levels drop. some aquatic organisms cannot live in low oxygen levels so populations fall.

69
Q

how does increasing human population affect waste

A

rapid growth in human population and increase in standard of living means increasingly more resources are used and more waste is produced

70
Q

under what condition is more pollution caused

A

if waste and chemical materials aren’t properly handled

71
Q

state three ways pollution can occur in water

A
  • sewage
  • fertilisers
  • toxic chemicals
72
Q

how does sewage pollute water

A
  • humans produce large amount of sewage containing urine and faeces
  • some countries release into nearby waterways
  • UK sewage treated before release - sometimes untreated sewage accidentally released into rivers or streams
73
Q

how do fertilisers pollute water

A
  • farmers add fertilisers to soil to ensure soil fertility year after year
  • minerals in fertilisers (esp nitrates) easily washed from soil into local streams, rivers
  • stimulates growth of algae and water plants; algae cover surface of pond
  • too much competition for light so unable to photosynthesise; therefore less oxygen in pond
  • plants die, decompose by bacteria and fungi which respire and use up even more oxygen

this is known as eutrophication

74
Q

how do toxic chemicals (e.g., pesticides and herbicides) pollute water

A
  • released into rivers from factories
  • can kill animals in the river due to bioaccumulation effect
  • largest carnivores die or fail to breed due to build up of toxic chemicals in their bodies
75
Q

how do fertilisers and untreated sewage in water kill aquatic organisms

A

they cause dissolved oxygen levels to fall
- eventually fall so low that all aerobic aquatic animals die

76
Q

what are bioindicators used for

A

monitoring pollution levels in waterways

77
Q

state two ways pollution can occur in air

A
  • smoke
  • acidic gases
78
Q

how does smoke pollute air

A
  • burning fossil fuels releases smoke (unreacted hydrocarbon particulates)
  • can suffocate certain animals
  • can lead to lung damage and other respiratory complications
  • can lead to global dimming; affects climate and hence affects distribution of many species
79
Q

how do acidic gases pollute air

A
  • human activities e.g., burning fossil fuels which often contain sulfur impurities
  • sulfur reacts with oxygen during combustion to form sulfur dioxide; causes breathing problems in high concentrations
  • leads to acid rain; destroys trees, soaks into soil and destroys roots, corrodes limestone buildings, can destroy whole ecosystems, alters pH of water - kills aquatic animals
80
Q

what is smog and how is it caused

A
  • a haze of small particles and acidic gases
  • caused from sulfur dioxide and nitrogen oxides
81
Q

state two ways pollution can occur on land

A
  • landfill
  • toxic chemicals
  • side effect of farming
82
Q

how does landfill pollute land

A
  • destroys natural habitats for plants and animals
83
Q

how do toxic chemicals pollute land

A
  • can leach out of landfills and contaminate soil for miles around
  • in some cases they’re dumped directly onto the land
  • chemicals can kill living organisms
84
Q

how does farming pollute land

A
  • farmers use chemicals to protect crops
  • these pesticides/herbicides are poisons
  • when sprayed onto crops, they also get into soil
  • from soil, washed out into streams and rivers
  • can also enter food chains and bioaccumulate
  • leads to dangerous levels of poisons building up in top predators
85
Q

how does pollution reduce biodiversity

A

by killing plants and animals

86
Q

how do humans reduce availability of land and what is the effect of this

A

by building, quarrying, farming and dumping waste, which reduces biodiversity as there are hence less habitats for plants and animals

87
Q

what do peat bogs contain

A

large amounts of dead plant material that decays very slowly

88
Q

why do peat bogs decay slowly

A

due to the anaerobic (without oxygen) and acidic conditions. also because of the waterlogging, as water cannot evaporate

89
Q

how do peat bogs act as unique ecosystems

A

they act as a habitat for a wide range of organisms, meaning they have a rich biodiversity

90
Q

what is a peat bog

A

a wetland in which peat has accumulated

91
Q

what do peat bogs act as

A

a massive store of trapped carbon

92
Q

uses of peat

A
  • cheap compost for gardens
  • good source of fuel
  • sometimes burnt to generate energy i.e., electricity
93
Q

disadvantages of destroying peat bogs

A
  • they’re being destroyed faster than they form
  • destruction of habitats which reduces the variety of different plant, animal and microorganism species that live there (biodiversity)
  • high CO2 emissions
94
Q

how do peat bogs contribute to climate change

A
  • once it has been extracted for use in compost, it begins to decay
  • this releases large amounts of CO2 into the atmosphere
  • when it is burnt for fuels it releases CO2 as well
  • CO2 is a greenhouse gas which contributes to climate change
95
Q

what is the disadvantage of peat-free compost

A

its more expensive so would increase price of food as farmers pay more to grow crops using the peat-free compost

96
Q

what has large-scale deforestation in tropical areas occurred to do

A
  • provide land for cattle and rice fields
  • grow crops for biofuels
97
Q

disadvantages of deforestation

A
  • disturbance of water cycle due to lack of evap from trees
  • increased co2 levels due to lack of photosyn from trees
  • burning trees releases co2 as it combusts
  • microorganisms feeding on decaying vegetation releases co2 via respiration
  • reduction in biodiversity, destruction of habitats and disruption of food chains - animals have less space to hunt + less prey to eat + less hiding space for prey
98
Q

advantages of deforestation

A
  • allows us to meet increasing demands for food as we have more room to grow food
  • we can grow staple foods e.g., rice, or make cheap food in the developed world e.g., palm oil
  • more space to rear cattle for beef market
  • to grow crops used to make biofuel e.g., ethanol from sugarcane
99
Q

where has the scientific consenus about global warming and climate change come from

A

it’s based on systematic reviews of thousands of peer reviewed publications - this helps to detect false claims and bias to ensure that research published in scientific journals is valid and accurate

100
Q

why do reports in the popular media not contain accurate information about global warming

A

they’re not subject to peer review meaning it can sometimes be oversimplified, inaccurate or biased

101
Q

what contributes to global warming

A

increasing levels of carbon dioxide and methane in the atmosphere

102
Q

how does global warming affect the distribution of species

A

animals may migrate to cooler areas which affects migration patterns

103
Q

how does global warming cause loss of habitats

A
  • in polar regions for example, polar bears lose their ice habitats, reducing biodiversity
  • rising sea levels destroys habitats especially in low-lying areas
104
Q

how does global warming reduce overall biodiversity

A
  • some organisms and species may not survive increased temperatures
  • some organisms cannot migrate if other habitats don’t have the right food source
  • many become extinct due to loss of habitat and changing conditions
105
Q

how can global warming spread disease

A

mosquitoes as an example
- right now the temperature is too cold for species of mosquito to survive in the UK
- possible that with global warming, temperature becomes hot enough for them to migrate here
- diseases such as malaria may be brought with them

106
Q

how can global warming affect plants

A
  • plants flower earlier due to warmer conditions
  • we may be able to grow crops in parts of the UK that need warmer temperatures if global warming increases
  • in other parts of the world it may be too hot to grow the crops they need
107
Q

programmes designed to maintain biodiversity

A
  • breeding programmes for endangered species
  • protection and regeneration of rare habitats
  • reintroduction of field margins and hedgerows in agricultural areas where farmers employ monoculture
  • reduction of deforestation and co2 emissions by some governments
  • recycling resources rather than dumping waste in landfill
108
Q

how do field margins and hedgerows on farms increase biodiversity

A
  • lots of different species of plants and animals use these as habitats
  • hence helps increase biodiversity on farms
109
Q

how do governments play a role in maintaining biodiversity

A
  • taking action to reduce co2 emissions
    e.g., generating electricity by renewable methods which doesn’t contribute to global warming
110
Q

how does recycling play a role in maintaining biodiversity

A
  • waste would otherwise go to landfill
  • landfill destroys habitats for plant and animal species’
  • this means fewer habitats destroyed which has a positive effect on biodiversity
111
Q

why have scientists and concerned citizens put programmes in place for biodiversity

A

to reduce the negative effects of humans on ecosystems and hence biodiversity

112
Q

how are trophic levels used

A

they’re represented by numbers starting at level 1 (producers). further trophic levels are numbered subsequently according to how far the organism is along the food chain

113
Q

what is on trophic level 1

A

producers - plants and algae that make their own food

114
Q

what is on trophic level 2

A

primary consumers - herbivores that eat plants/algae

115
Q

what is on trophic level 3

A

secondary consumers - carnivores that eat herbivores

116
Q

what is on trophic level 4

A

tertiary consumers - carnivores that eat other carnivores

117
Q

define apex predators

A

carnivores with no natural predators (top of the food chain)

118
Q

what do decomposers do and how

A

they break down plant and animal matter by secreting enzymes into the environment. enzymes digest the dead materials and the small soluble food molecules then diffuse back into the decomposer (the microorganism)

119
Q

what do pyramids of biomass represent

A

the relative amount of biomass in each level of a food chain - trophic level 1 is at the bottom of the pyramid

120
Q

what causes losses of biomass between the different trophic levels

A
  • not all ingested material is absorbed; some is egested as faeces
  • some absorbed material is lost as waste, such as carbon dioxide and water in respiration, and water and urea in urine
121
Q

what percentage of biomass is transferred to the trophic level above it

A

only approximately 10%

122
Q

how much incident energy do producers transfer

A

they transfer about 1% of the incident energy from light for photosynthesis

123
Q

how to calculate biomass of caterpillars in an area

A
  • gather them
  • kill them
  • dry them out
  • weigh them
    this gives us the dry biomass
124
Q

features of compost bins

A
  • open at the bottom; lets decomposers enter
  • some have air holes; allows oxygen in for decomposers to respire
  • black in colour; absorbs heat to increase temp (faster rate of reaction)
  • loosely fitting lid; allows oxygen in for decomposers to respire
125
Q

what is the problem with measuring dry biomass

A

it will kill the organism as you’re dehydrating it

126
Q

why is wet biomass less useful than dry biomass

A

moisture content varies between organisms so can give inaccurate results

127
Q

define biomass

A

the (often dry) mass of material in living organisms

128
Q

define food security

A

having enough food to feed a population

129
Q

biological factors threatening food security

A
  • increasing birth rate
  • changing diets
  • new pests and pathogens
  • environmental changes
  • cost of agricultural inputs
  • conflict
130
Q

how does increasing birth rate affect food security

A

as population grows, amount of food available will have to increase to feed the whole population

131
Q

how do changing diets affect food security

A
  • in developed countries, tastes are changing
  • we now expect to eat a whole range of different foods throughout the year which cannot be grown in that country
  • therefore scarce food resources are transported around the world which can threaten their food security
132
Q

how do new pests and pathogens affect food security

A
  • pests eat food crops e.g., caterpillars
  • pathogens cause infectious diseases
  • if spread to farms, this reduces the amount of food crops available to eat
133
Q

how does environmental change affect food security

A
  • changes rainfall patterns; some countries may not be able to grow enough crops to feed a population
  • leads to widespread famine
134
Q

how does cost of agricultural inputs affect food security

A
  • GM crops withstand environmental change to increase yield; increases cost of seed so more expensive; makes it less affordable for consumers
  • irrigation systems, fertilisers and pesticides all cost; thus reducing food security for some
135
Q

how does conflict affect food security

A
  • violence prevents planting
  • no crops growing means stores are depleted
  • little to harvest and violence means markets are closed
  • food runs out
  • labourers like farmers that are needed to grow crops leave the country out of fear of safety
  • lack of migrant workers like farmers come to grow crops
  • highly unlikely that food imports are possible
  • country becomes over reliant on aid and donations which reduces food security
136
Q

how can we feed all people on earth

A

by finding sustainable methods

137
Q

how can the efficiency of food production be improved? how can this be done?

A

by restricting energy transfer from food animals to the environment which can be done by:
- limiting their movement; less energy used to move around
- controlling the temperature of their surroundings; less energy used to regulate their body temp themselves
- fed high protein foods to increase growth

138
Q

ethical objections to some modern intensive farming methods

A
  • poor animal welfare
  • some people think it’s cruel
  • livestock in confined spaces are more prone to disease
  • unethical to make livestock live in unnatural and uncomfortable conditions
139
Q

why are movement and temperature control restricted in intensive farming

A

both of these processes use the energy released from respiration. more energy is therefore available for growth as livestock don’t have to carry out these processes

140
Q

advantages of modern farming techniques

A
  • use less energy for movement so more energy used for growth
  • antibiotics prevent diseases and bacterial in livestock kept in close proximity to each other
  • monoculture maximises yield and profits for farmers
  • fertilisers increase plant growth and therefore maximise food production
  • removing hedgerows makes farms bigger and easier to maintain; more land available for crops
141
Q

disadvantages of modern farming techniques

A
  • keeping animals in close proximity is argued unethical as disease can spread easily
  • use of antibiotics can lead to antibiotic resistance
  • monocultures support a low level of biodiversity
  • runoff from fertilisers leads to eutrophication and eventually the death of aquatic organisms
  • removing hedgerows reduces biodiversity as they act as a habitat for a wide range of organisms
142
Q

what is happening to fish stocks right now? why is this potentially dangerous?

A

they’re declining, mainly due to overfishing. it is important to maintain fish at a level where breeding continues or certain species may disappear altogether in some areas

143
Q

consequences of overfishing

A
  • some species disappearing or even going extinct
  • ocean food chains being disrupted, affecting many other aquatic species
  • fewer fish for human consumption; especially problematic for countries that rely on fish as a main food source
144
Q

restrictions on fishing

A
  • fishing quotas to conserve fish stocks at a sustainable level; limit number of fish you can catch
  • larger holes in nets to allow small, young fish to escape and reach breeding age before they are caught and killed, which replenishes population of fish species
  • larger holes in nets so unwanted fish species can escape provided they’re smaller than the target species
145
Q

define biotechnology

A

the alteration and use of living organisms to produce products for human use

146
Q

what do modern biotechnology techniques enable

A

large quantities of microorganisms to be cultured for food

147
Q

modern biotechnology techniques

A
  • genetic modification
  • ability to culture large quantities of microorganisms for food
148
Q

what are the hopes for modern biotechnology

A

that it may be able to help provide sufficient food for the increasing human population

149
Q

what is fusarium and what is it used for

A

a fungus useful or producing mycoprotein, a protein-rich food suitable for vegetarians

150
Q

how is fusarium grown

A
  • grown on glucose syrup to allow respiration
  • aerobic conditions
  • the biomass is harvested and purified

fermenters are kept at optimum pH and temperature for fusarium to grow

151
Q

how can we produce insulin with biotechnology

A
  • gene for human insulin inserted into bacteria
  • bacteria then produce human insulin which can be harvested and purified
  • used medically to treat people with diabetes
152
Q

how can GM crops be used to cater for increasing human population

A
  • they can provide more food
  • they can provide food with an improved nutritional value e.g., golden rice

bio spec (9 decks)

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