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A-level Biology > Module 4.2 > Flashcards

Module 4.2 Flashcards

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1
Q

what are tropical rainforest extremely rich in ?

A

living organisms , including plants animals , fungi and microorganisms .

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2
Q

what is the meaning of community ?

A

population of living organisms in a habitat

a

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3
Q

what is the meaning of biodiversity ?

A

the variety of living organisms we find ina regions .
rainforest high
artic low .

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4
Q

why is it important that human activity does not have a negative effect on biodiversity ?

A

as all the organisms in a habitat depend on each other .

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5
Q

you can assess the degree of biodiversity in three levels , what are they ?

A

habitat biodiversity
and genetic biodiversity
species biodiversity

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6
Q

what is the meaning of habitat biodiversity ?

A

habitat biodiversity , refers to all of the different habitats , that we find in an area .
-the uk have a relatively large range of woodland meadows , so uk has a rich habitat biodiversity .

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7
Q

each habitat , will support a range of different species of animal fungi and microorganisms .

A

-so an area , with a rich habitat biodiversity will also have a wide range of species .

-regions –> artic has a relatively small number of different habitats .

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8
Q

what does species biodiversity tell us ?
-what subcategories can it be divided into ?

A

tells us about the species living in a certain area .
it has two parts
-species richness
-species eveness

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9
Q

what is species richness ?

A

counts the number of different species present .
-can also find these species in farmlands , hedgerows and around the fields .

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10
Q

as woods and farmlands , have a similar variety of different species , what could u conclude ?

A

you can conclude , that they may have a simialr species richness , however , the population sizes of these species will not be the same between woods and a farm .

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11
Q

what are the differences between woods and farms ?

A

woods may contain relatively large number of each species with no single species dominating .
-on the other hand , a farm is designed to support a very huge population of species .

-for example a a farm could have several huncpws or fields containing millions of wheat plants .
-whereas may be only a smell number of hedgerow’s .

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12
Q

what is species evenness ?

A

compares , how many individuals of each species there in a community .

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13
Q

what are the similarities between a woodland and farm ?

A

they have similarities in species richness .
-BUt , because the populations of each species is more balanced ina w woodlands .
-the woodland will have a much greater species eveness .

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14
Q

what is genetic biodiveristy ?

A

considers a variety of genes and alleles within a species .

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15
Q

fun fact timeee

A

humans 22k genes
fruit fly 15 k
some have more than 45 k

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16
Q

what is an allele ?

A

different versions of a gene

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17
Q

what does genetic diversity of a species depend on ?

A

it depends on the different genes and alleles present .
-for example the breeds of cats

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18
Q

what does allleles present ?

A

alleles present in different breeds , leading to different pehtnoyprsd .

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19
Q

why is genetic biodiversity important for insects ?

A

important for their survival .

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20
Q

species with a greater level of genetic biodiversity …

A

can better adapt to environmental change .

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21
Q

another benefit of a
greater variety of genes .

A

if a species faces a new pathogen , having a greater variety of genes and alleles makes it more likely that the species will survive .

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22
Q

as there is a wide range of species in a woodland what does this menann

A

woodlands have a complex food web .
-+food sources are abundant , this makes a woodland stable and ecosystems where the number of species in fairly stable .

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23
Q

what is a desert like ?

A

deserts have a much harsher habitat .

-conditions here are very challenging for living organisms . for example , the the temperatures can be extreme and there a few sources of water .
-species we find are highly adapted deserts in deep conditions /

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24
Q

biodiversity of deserts ?

A

deserts have a low relatively ;pw biodiveristyr meaning food was often relatively scarce

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25
Q

what is the simpson’s index ?

A

used to determine species biodiversity of an area .
-total number of rogansims of a particular species .
-total number of organisms .

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26
Q

lower number of simpson number

A

lower level of biodiversity .

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27
Q

sewage ooooooutracks

A

have a high level of pollution and low levels of dissolved oxygens .
-organisms that liv in here condense a re highl twhat

-so areas are heavily polluted tend to have a low biodiversity .
-with a small number of species adapted to live in those conditions .

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28
Q

what is genetic biodiversity also known as

A

the gene pool

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29
Q

key ; all the different individuals have the same what ?

A

they have the same genes .
-most genes onlyhave ne version , this is called monomorphic .

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30
Q

howeevr , some genes have different vesrsions ofegens called alleles , what is this known as ?

A

for example the genes controlling coat colour in dogs .

coat colour in dogs have a different number of alleles , scienits call with differentr alleles olymprohic

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31
Q

what are pure breeds like ?

A

pure breeds tend to have a relatively low genetic bidoivieristy .
-this is because , all th breed takes small huh , -these aew swlwxted by hormones .

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32
Q

number of diffewrent alleles within this

A

population is relaitevely small
-number of alleles allowed to enter the breed ..
-causing inrbreedig within hte populatio ,,
-inbreeding causes geenticallyy linked porbelms . example cancerr

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33
Q

what is the benefits of mongrel dog ?

A

the breeding is random .
-meaning mongrels have a wide range of alleles and a high level of genetic biodiversity .

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34
Q

what type of dogs , is health problems , more of an issue ?

A

genetic problems are less of common in mongrels than pure breed dogs

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35
Q

how can we quantity genetic biodiversity

A

check sheet for the equAITON
-GENES THAT ONLYHAVE ONE ALLELE IS MONOPORPHIC .

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36
Q

WHAT IS A GENE LOCUS ?

A

THE POSITION of a gene on chromosomes .
-gene loci simply means the position of a gene on a chromosome .

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37
Q

there are only two ways that genetic biodiversity can increase , what are they ?

A
  1. random mutations can take place , creating a new allele .
  2. migration between populations can transfer alleles .
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38
Q

example of migration of animals

A

alapacca migrate into different group of alappacas .
-the individual may have different alleles when interbreeding takes place .
-these alles can now enter the populations on the gene pool .

-scientists call this genetic flow .

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39
Q

what is one way genetic biodiversity can decrease

A

as a result of natural selection , individuals with an advantageous alleles arem ore likely to survive and reproduce than individuals with a disadvantageous alleles .

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40
Q

what will hapen to less advanatgeous alleles overtime ?

A

-overtime , less advantageous alleles will become less common in the population . so natural selection ,can reduce genetic bidoiversity .
-so natural selection reduces biodiveristy

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41
Q

What happens in selective breeding / rtifical selection ? awhy does this happen

A

-Humans select individuals in a population for breeding .
-as those individuals have alleles which are seen as advanatageous .

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42
Q

give an example of selective breeding

A

-selective breeding has been used to crrate varieties of cattle and crops .

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43
Q

what happens to individuals withouht the desried alleles in selective breeding ?

A

-they are not allowed to breed .
-so overtime , these alleles diapper from the population .

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44
Q

How can selective breeding result in breeds , which fall out of favour ?

A

+ become rare .
example manc loaghtan sheep . (1950s 0 this became rate as 43 are only
-due to the small numer of indivuals , egentic bidoivieristy within this breeed decreased .

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45
Q

-How iwll the number of idnivudals of a wild species decrease ? give an example

A

for example due to hunting .
-only 400 sumatran tigers left int he wild .
-200 in zoos , these are bred to increase numbers .

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46
Q

whats wrong with trying to breed sumatran tigers ?

A

-with sucha small number of individuals , the size of the GENE POLL , is very small .

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47
Q

How can geentic BIODIVERISTY be reduced by clonng plant ?
-explain how the cloning porcess is done ,a nd the effect of this .

A

-many gardeners take cuttings of plants with desribale features .
-when thse cuttigns are planted , they grow into new plants . identicial to the orgiinal .
-as these plants are allc lones ,genetic biodivieristy within the species decreases .

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48
Q

sometimes , the population sof a species iwll crash to an extremely low level . (blck robin exmple )b , explain what happened to do the balck robin population ?

A

-rats and cats wwere intorudced to the isalnds by humans .
-causing the black robin populaiton to collapse . -1980s onl 5 left with one fertile bird , all the descendants of theb lck robin , s conservationist icnrease opualtion ,c ae fromt hat one fertile female.

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48
Q

what is itcalled when the gene pool is severly redued like in the black robins ?

A

-scientists call it a geentic bottle neck .
-genetic bottlenecks ,s everely reduces denetic niodiviersity .

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49
Q

-sometimes , genetic bidoivieristy can chnge due to random c hance .

A

-scienitnits call this genetic drift .
-for example , some individuals , within the oppulation , may not reporduce .
-if these idnvinduals re the only ones with a ceertin allele . hten that allele will be lost .

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49
Q

what happens when a small number of indivudals moive ?
-what is this called ?
-explain using the wolves from isle island .

A

-they form an isolated population with limited gentic biodiveristy.
-scientists cal this ht efounder effect . *0
-isle royal .
-allwmolves ebcame desvednayt from the smll opulation inially .
-but hen anpther wolf came along , increasing the biodiverity genetic

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50
Q

when is genetic drift , most likely to occur ?

A

-when a population is small and has low genetic biodiveristy .
for example after geentic bottle neck has taken place .

-geetifc drift is RANDOm and is not linked to any geature of an allele .

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51
Q

how to sceienitts cifgure out the species biodiveirsity in a habitat ?

A

acienitsts carry out sampling .

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52
Q

sampling techniques can iehter be what ?

A

random o r non-random .

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53
Q

what hppens in random sampling ?

A

the areas , that samples are aken form are selected by using random numbers
-these radnom numbers can then be used to determine the coordinates on a map .

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53
Q

non- random sampling , the three types , wha are they ?

A

-oppporunistic -
startfied sampling

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54
Q

advanatge of random sampling

A

-as the area is not chosen by a human , random samploing , reduces the chnce of ampling bias .
-if a human chose arera , they might choose area eiest to reach .or rea with large number of organisms , hwoever .these areas might not be typical for the whole habitat , REDUCING THE RELIABILTIY of the sample

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55
Q

Wgaht happens in opporunitditc smpling ?

A

th scienitsts seelct the organsms thatt are readily available .
exmpel edge of pond ,w here they cn be easily sampled .

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56
Q

what is the problem with opportunistic smpling ?

A

-these organsms s , lmay not be representatie of the organisms in the pond .,
Making opportunitic sampling , unrelible

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56
Q
A
57
Q

problem with stratified sampling ?

A

more maale fish than female fish
-what if males have a greater mass tha females . 4
-in this case ,rather than seecting anyf isha t random , it is more reliable to todivide popualtion into males ansd feamles
-then take randm samplings frome ach subgroups .

57
Q

what happens in stratified sampling ?

A

-the populations is divided into sub groups or strat .
-fish in lake with mass example .measuring their mass

58
Q

what is key about stratified samplign , using the fish example to explain ?

A

-we need to make certain , that the number of males and females we select . is represnetaitve of the numebrs in the alkes

(if there are twice as many males than femlaes thenw e need to emasure 2 males for every female ) .

59
Q

when is systemtatic sampling used ?

A

when there is a gradual change in the habitat from one palce to another .
-i this case ,w e want to determine , how the abundance o organisms changes as the habitat changes .
-OR we could looka t how the features of organisms CHANGE .

60
Q

two ways of doing this ?

A

-is using a line transect and a belt transect

61
Q

what happens in a line transect ?

A

-in a line transect , a measuring tpe is placed across the habitat .
-any organisms , touchign the tape is sampled .

62
Q

what is the problem with a line transect ?

A

-the number of organisms touching the tape may e ver small .

63
Q

alternative to a balet transecanother e way of doing a ble ttransect ?

A

we can sample orgnaimsms at regualr intervals along the transect .
-this is called an INTERRUPTED ELT TRANSECT

63
Q

what happens in a belt transect ?

A

we place two parallel tapes across the habitat .
-an organisms foudn between the two tapes are sampled . for example by using a quadrat .

64
Q

What is the purpose of sampling organisms , ?

A

we can estimat the number ina given area . number off organisms scientists call this the abundance of o.ganisms ..
-can also make estimated about the features of an organisms . for example its amss .

64
Q

one problem , faced by any sampling method ?

A

i the issue of chance .
-if we select an organisms , there is a chancw that that organimsms may not be typical for the whole group .

65
Q

how can reduce the problem of ll sampling techniques pne ?

A

sampling a very large number of organisms .
-this makes it more likley that the measurements we take , are represnettive of the entire population . increasing the reliabiltiy of our sampling .

66
Q

sampling plants - insects in a meadow
TECNHIUQE ONE IS SQWEEPING NET .

A

sweeping net is sept over the plants multiple times . this traps any isnetcs present .

-small insects can be caught direclty using a pooter .

67
Q

-technique two
a pooter is used to catch insects directly , explain how it works ?

A

a pooter consits of a container with two tubes the trapping tube is palced near the insect we want to catch . we place the motuhpeice tube into our mouth and gently inahle .
-he insect is now sucked itno the trpapping tube and intot he container .
-the mouthpiece tube has a piec eof cloth , to top n insect being sucked into the mouth .

68
Q

tecnchiqu three –> how do we trap ground level animals like insetcs or snails

A

we use a pitfuall trap .
-a pitfallt rap is a container sunk into the ground .
-oveer the trap l, we palc e acover which preents rainwater from comgin ing .

–ground leel amilas fall into the trap . which is deeep enough for them to stop crawling out .

69
Q

technique four how do we sample the tiny animals present in soil ?

A

-then we can use a tullgren ufnnel .
-the soil sapmpel is place dina funnel above the continer , a light ulb gently hrets the surface of the soil .
-the animals i the soil move downwardds ,a way fromt he heat , once the aniamls reach the bottom of th funnel , they fall linto the container ,

70
Q

technique five , ohow do we sample btoom dwelling animals ?

A

kick sampling is used to sample bottom dwelling animals .living in ERIVWR BED .
-A NET IS PLACED DOWNSREA , THE SCIENITST GENTLY KICKS THE RIVER BED TO DISLOFGE ANYR OCKS OR PEBLES .
-ANY ORGANISMS WHICHA RE DISTURBED , MOVE DOWNSTREAM AND ARE CUAGTHT IN THE NET .

71
Q

TECNHQIEUE SIX – > slow moving or static animals — > excample on a sea shore >

A

then we can use a frame waudrat .
- a frame quadrat is palced ont he gorund ,a nd any naimal within the waudrat is sampeld .

-imaigne we use a wudrtat whcih i 1 m2 , then the actual number of plant species example dasies , denisty per m2 i what the number of aninumber we cont . This s a highly accurate sampling method .

72
Q

-some plants are difficult to count , fro example moss or we may have a plant with a very alrge number like grss . do how do we sample these ?

A

-in these cases , we looka how manys mall squares withint he wudrat , contain the paln .
-we then report this number as the percentge frequencye .
-exmpale 100 smll squares
-moss ofund in 2 squares
-then frequency of msoss , is 20/100 = 0%

-KEY , notie not sayign how omcuh of each square is ocvered in mosss , just aying “ this is the percentage of small squares that contain moss .”

73
Q

-what does it mean if palnt occupies a alrge proporition of the quadrat ? hen what do we estimate ?

A

the we simply estimate by eye what percentage of the total quadrat area is occupied by hte plant .

74
Q

stregnths and weakness of percentge cover ?

A

-percentage ocver is a very rapid way of sampling but it is the least accurate emthod .

-in allc ases , we can increase reliaility ,by placing the wuadrat in multiple postiosn . and calcualting a mean .

74
Q

-wht can we use instead of a frame quadarat we can sue a point quadrat , how does this work ?

A

-a point qudrat is a wooden bar ith holes in it .
we positiont he bar over the gounrd , and palce metal pins into the each hole .

-we cont any palnt which is touched by the pin .

74
Q

-an increasing human population , presents a mjor challenge to the biodiversity on earth . … give on problem >

A

-feeding a large human population , reqruies intenisve farming methods .

75
Q

second problem with athe growing population

A

human adctiity reqruies a great deal of spc which is leading to the destruction of forests .

76
Q

third problem with growing population

A

lastly , carbondioxide from burinijg fossil fues is eding to climate change .

76
Q

sstrengths oimpact of reqruing a great deal of food for increasing human population

A

the vast amjority of food ebcomes for farming .
-farming frming is used to support a very large population ofa very small number of spcies .

so farms already have a relativley low lwevel of biodioveirsty .

77
Q

where are monocutlures gorwn ?

A

-big fields which marke harvesting mroe efficnet .

-ino rder to create these fields , hedgrows are dug up hedgeros contian a rich diveristy of plants and animals , so hedgerwos desoiryed htese re lso .

78
Q

-what happens when a field only contins one crop , suchas wheat

A

this is called a monoculture .

-herbicides are used to kill any unwated palnt species . which are regaded as weeds .
-pesicides are used to killan insects which might eat the crop .
-so a monoculture has an extremel low level of biodiviersity . 000000000000000000000000000000000000

79
Q
A
79
Q

which contain

A
80
Q

which contain more than hal of all animal and plant species on earth

A

…

80
Q

lastly , stly forests are cleared to mke land for frming this incldues tropical rainforests .

A

which contain more than hal of all animal and plan species on earth .

80
Q

-as you can see modern farming method have a nagaive impact on biodiversity .

A

-As we gave see n forests arecleared to provide land for farming .
-the clearing of forests is called deforestation .

81
Q

-deforesttion is also crried out for ?

A

– this produces carbonxide to provide wood for consturction and for fuels
-or to porvide lad for cities and orads .

81
Q

carbondioxide is also produced when fossilf uels such as coal oil and gas ., are burned for energy .0

A

the level of co2chasincreased significantly over past 200 years .
-this is l0

82
Q

-Mean temperture of the surfae of the earth is increaisng , what do scientits call this ?

A

sscienitsts call this global warmng .

83
Q

where else is carbondioxide produced ?

A

-when fossil fules usch as coal , oil and gas are burned for eergy .
-the level of carbondixoide int he amosphere has increased signifcintly for the last 200 years .
-most sceinits accept , this i leading to climate change , for example ,c ahnegs to rainfall ptterns ,w ind patterns and global temperatures .

84
Q

what is the impact of global warming on biodiveristy ?

A

-global warming will have a nagetive impacto n biodivieristy .
-firstly , rising temperatures are causing hte polar ice caps to melt .
-The oss of polar habitats could lead to the extincition of animals and plants . that currenlt live there .

85
Q

As temper ature increases wter e xpadnsds .

A

-along wigh the metling ice caps , this is elading to n increse in global sea levels .
-as sea levels rise , this will led to flooding . Adnd the destruction of low-ling habitats . reducing bidoivieristy .

86
Q

Another fctor tht is impcted , due to riding tempertures ?

A

rising temperatures could cuase rthe death of mrine organismss
for examples as corals , s welllas alter the distribution of fish .

87
Q

what will happen as gobal temperatures will increase

A

droughts will become more commin .
-s many plants cannot cannot usrvive udner drought conditoins . so this could affect the disrubtiono f palnts in many habitats .

87
Q

-this willa ffect the distributiono f animals which depend on thoe plants for food .

A

…

88
Q
A
88
Q
A
89
Q

what is the last effect of gobal tempertures incresing ?

A

-it changes the disdtirbution of plolliantors in the world .like insecs .

-this hten in turn , could ffect the distribution of plants . as wella s the animals that dpend ont hem .

90
Q
A
90
Q

why bidoivieristy should be preserved 1

A

-firstly , many people believe that a rich diveristy of plant and animal contirbute to the beuatyo f the earth .
-this is called an aesthetic reason Millions o eople enjoy visiting the ountryside . to expereicne nature , for example in woodlnds or the seashore .

-for cenutres ,a rtist msucins have found insoo form nature .
so asesthetic value is one reason why it hsould be preserved .

90
Q

2 reson why biodivierisyt should b prsevred

A

-the rich variety of paln of plants int he tropical rianforest . could be extremly improtat in the furture .

  • as te climate chnages ,c rops which we use for food , ay struglle to gro w.
91
Q

2 reason why biodivieristy hsould be preserved ?

A

-tehere are also economic resons for preserving biodiviristy .
-tropicl rainforests under threat of deforestation - rainforets contina wide vriety of plnt and animal ufngi micorgoraniams .
-many of these could be potenitl sources of futurre medicines . so it is essential they are preserved .

92
Q

WHA DOES CROSS BEEDING D ?

A

B y crossbreeding existing crops with rainforest palnts , we ma be able to intorduce geens and alleles 0that help he crops to trhvie as environemtnl conditions change .
-however , if we continnue destroing rainofrests , we will lose this geentic biodiversity for ever .

93
Q

one major reson for deforestation ?

A

the produxtion of wood as this is not sustainable o

94
Q

solution to deforestatrion

A

-if forests are presevred they can provide wood now and also int he future .

selective logging and replanting trees .

95
Q

-many people value value the opportunity to visit and experience rich biodiversity .

A

if done sustainably , tourism can provide a valuable source of income for these regions .

95
Q

for all thes eeconomic regions

A

its important that we preserve the biodiversity of the forests /.

96
Q

many farms result in a loss of biodiversity , give an example ?

A

for example , many farms have vasty fields of only one crop .
-this is called a monoculture .

97
Q

why does farming a very small number of plant species present an economic risk ?

A

-many plant species may struggle due to climate change .

98
Q

why does farming a very small number of plant species present an economic risk ?
solution

A

-we can reduce the risk by increasing the diversity of plants grown on farms .
-that way in the future if some crop species , struggle to thrive . . we can turn to to other crop species for food instead .

99
Q

what can farming only one type of crop do to the soil ?

A

-it can deplete the soil .of certain nutrients and minerals .
-this can then require farmers to use more and more .
farming a wide variety of crops helps to reduce this problem .

100
Q

give an ecological reason for maintaining biodiversity

A

-in any habitat , all of the species of living organisms depend on each other .

101
Q

give an example of organisms depending on each other

A

-for example , many organisms will be a food source for other species .
-species such as bees , act as pollinators .

102
Q

another example of organism depending on each other

A

organisms such as fungi are decomposers breaking down dead organisms , and allowing nutrients to be recycled within the habitat .

103
Q

what is a keystone species ?

A

certain species play a very significant role within a habitat .

103
Q

give an example of a keystone species ,a nd their function .

A

-good example is sea stars .
-sea stars are predators for mussels .
-in the absence of sea stars , mussel populations increase dramatically .
-the effect of this is to crowd out seaweeds ,s onges and anemones .

104
Q

what does the presence of sea stars do the biodiversity of the habitat ?

A

-increases the species biodiversity .
-so because all of the species within a habitat depend on each other . This is an ecological reason to maintain biodiversity .

105
Q

what is biodiversity under threat by ?

A

human activity .
-which has led to many species becoming endangered - these species are likely to become extinct in the near future .

106
Q

one way to protect endangered species is in situ conservation , explain what this is ?

A

-in situ conservation takes place in the organism’s natural habitat .

107
Q

give an example of in situ conservation ?

A

for example creating a wildlife reserve .

108
Q

what happens in a wildlife reserve ?

A

special measures are put in place to help protect the organism /.

-for example , human access may be restricted as we;; as hunting or poaching .

109
Q

what happens if the number of species , fall , very low in an area ?

A

then it might be reintroduce from populations living elsewhere .
-in the case of animal species , they may be provided with food .

-any species which is not native to the area , in other words an invasive species , may be removed to protect competition with the protected species . this is especially important in the case of protected plants /, which can easily be outcompeted

110
Q

what happens to land int he uk , if it is left overtime , what is this process called ?

A

it will naturally revert to woodland .
-This process is called succession

111
Q

why is succession a problem for a number of habitats such as moorland and heathland .

A

-to protect these habitats , grazsing organisms such as deer can be introduced .
-these graze on saplings and prevent the succession to woodland .

112
Q

how can endangered marine species be protected ?

A

by marine conservation areas .

113
Q

what is prohibited in marine conservation areas ?

A

tourism , fishing . and extraction of oil and gas are controlled.
-movement of ships through these areas can also be restricted .

114
Q

what happens on ex situ conservation ?

A

ex situ conservation takes place outside of an organism’s natural habitat .

115
Q

good example of ex situ conservation ?

A

a good example is captive breeding programs that take place in zoos .

116
Q

problem with ex situ conservation ?

A

because of the relatively small number of organisms in a zoo , inbreeding can be a problem ,

117
Q

solution to the problem with ex situ conservation ?

A

zoos keep detailed family trees so that closely related animals are not mated .

118
Q

what happens when animals reintroduced from captive breeding , return back into the wild ?

A

-it may not necessarily be possible for example if their habitat has been reduced or destroyed .

119
Q

why may a reintroduced animal may not be able to go back to their orginal habitat .

A

a new disease may be present in their habitat which could prevent their reintroduction .

120
Q

how can ex situ conservation be applied to plants ?

A

-rare plants can be cultivated in botanical gardens .

121
Q

ex situ conservation in plants (2)

A

the seeds of rare plants can be stored in seed banks .

122
Q

what happens in seed banks ?

A

dried seeds are kept at cold temperatures to preserve them .
-this is particularly important in the case of crop plants . Which have been produced by selective breeding from wild plants .

123
Q

a good example of the selective breeding is what ?

A

-modern wheat .
-which is derived fromw ild grasses bred over thousands of years .

124
Q

what might happen to modern wheat in t he future ?

A

-as the climate changes , modern wheat may no longer be able to thrive .

125
Q

how can modern where survive ?

A

by cross breeding with its wild relatives , we may be able to introduce beneficial alleles .
-these alleles may help the wheat to adjust to climate change .

126
Q

conservation efforts are backed by a number of international and local agreements , give an example ?

A

in the uk , the countryside stewardship scheme was set up to encourage farmers to preserve wildlife and habitats .

127
Q

many plants and animals are traded between different countries .

A

-the convention of international trade in endangered species was established to regulate this and ensure that it does not threaten the survival of species which are endangered .

128
Q

what is the rio convention of biological diversity ?
-what doe s this agreement promote ?

A

-agreement , signed by a large number of countries in 1992 .
-this agreement promotes sustainable development , as well as measures to protect biodiversity .

A-level Biology (21 decks)

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