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A-level Biology > Module 6.4 > Flashcards

Module 6.4 Flashcards

1
Q

What are clones

A

Clones are genetically identical organisms or cells .

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2
Q

what is vegetative propagation

A

reproduction from vegetative parts of a plant - usually an over wintering organ

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3
Q

how are clones produced

A

clones are produced by asexual reproduciton in which the nucleus is divided by mitosis .
-Mitosis creates two identical copies of the DNA ,w hich are then separated into two geneticlaly idetical nuclei before he cell divides to fom two genticlaly idential cell .

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4
Q

advantages of natural cloning part one

A

if the conditions for growth are goof for hte parent , theyw ill aloso be good for the offspirng

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5
Q

advanatges of natural cloning 2

A

cloning is relatively rapid - so the population can increase quicky to take advanatage of the suitble environment onditions .

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6
Q

advanatges of natural clonign 3

A

reproduction can be carried out , even if there is on one parent and sexual reproduction is not possible

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7
Q

disadvantages of natural cloning

A

offspirng may become over crowded

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8
Q

disadvanatges of natueal cloning 2

A

no genetic diversity

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9
Q

disadvanatges of natural cloning 3

A

the population shows little variation

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10
Q

disadvantages of natural cloning4

A

the selection is not possible

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11
Q

disadvanatges of natural cloning 5

A

if the environment changes to be less advanatageous the hwole population is suscpetible .

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12
Q

what are rubbers or stolen

A

more plants grow horizontal stems that can form roots at certian points . if they grow on the surface on the growud

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13
Q

what ae rhizoomes

A

if they re udnergodud
-sime are rhizozomes are adapted , s thickcened over wintering organs from which one or more new stems will grow in the spring .

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14
Q

what are suckers

A

suckers are new stems from the roots of plant - these may be close to the base n older stem or could be distanced away . In all cases , the original horizontal branch may di ,leving the new stem as a separat indivudal .

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15
Q

what are bulbs

A

they are an over-wintering mechansisms for many perennial moncotuledoous plnts . BUlbs consist of an underground stem from which grow a series of fleshy leaf bases .

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16
Q

what apixla buds

A

which will grow into a new plant in the spring . OFTEN , a bulb contains mroe than one apical bud a dn each will grow into new pl .

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17
Q

what are corms

A

corms are often mistaken for bulbs , HOwever , corms are solid rather than fleshy like a bul .
-A CORM , is an underground stem with scaly leaves , nd buds . Corms remain in the ground over witner , In the spring the buds grow to produc on or more new palns

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18
Q

what are leaves

A

the kalanchoe plant reproduces asexually , , as clones foew on rhe leaf margins , the immature plants drop off the leaf and take root .

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19
Q

what are tubers

A

tubers are another type of udneround stem . POTTOES ARE TUBERS , ONE POTATO WIL GROW INTO ONE OR MORE PALNTS ,E ACH NEW PPLNTS CAN PRODCE MAN NEW TUBERS .

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20
Q

NATURAK CLONING in mammals

A

mammals clone when idneitical twins are formed . THIS IS WHEN A FERTILISED EGG (ZYGTOWE) divides as normal , but the two daughter cells then split to become two separate cells . ERach cell gorws and evelop into a new idnviidual .

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21
Q

what are micropropagation

A

growing large numbers , of new plants , from meristem , tissue taken from a sample plant .

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22
Q

what is tissue culture

A

growing new tissues , organs or palnts from certain tissues cuts from a sampel plant .

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23
Q

what i the way of cutting stem overview

A

to make a cutting , a stem is cut betwee two elaf joints . (NODES ) , the cut end of the stem is then palced in mosit soil . new roots will grow from the tissues int he stem 0 usually from the node , but they amy grow from other parts of th eburied sem

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24
Q

what to do if a plant does not take root easily

A

-other plants ma need further treatment
-Dipping , the cut stem , in rooting hormone helps to stimulate , root frwoth .
-It may also be helpfl to wound or remove the bark from the cut en dof the stem as this encourgaes the plant to produce CALLUS .

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25
Q

First place cutting can taje place

A

root cuttings in which a section of root is buried just below the soil surface and produces new shoots .

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26
Q

second place cuttings can take place

A

scion cuttings , which are dormant woody twigs .

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27
Q

third place cutting can take plce

A

leaf cuttings , in hwich a leaf is placed on moist soil . The leaves , develop new steams and new roots , Some leves my produce many new plants from one cutting .

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28
Q

what conditios is tissue culture carried out in

A

tissue culture is a techianue used to grwo a SMALL SAMPLE of ells or tissues . IT IS CARRIED OUT in a nutrient medium under sterile conditios .
-THE APPLICANTS OF PLANTS , growth usbtances at the correct , tie can encouage the cells in the growin tissue to differentiate .

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29
Q

microprogaation step one

A

suitable plant mterial is selected and cut into small peices . These re called explants . Explants , could be tiny pieces of leaf , stem , root or bud . Mmeristems , tissue is often used as this is always free from virus infection .

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30
Q

micropropagation step two

A

the expalnt are sterilised using diulte blech or alcohol . This is essential to kill any bactieria and fungi , as these would thrive in the conditions supplied to help the plant grow well .

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31
Q

micropropagation 3

A

the explants are placed on sterile growth medium , contining suitable nutrients , such as glucose , amino acids and phospahtes .
-The gel also contains high concnertations of the plant growth substanes , auxin , cytokinin .

-THIS STIMULATES , THE CELLS OF EACH explant , to dividie by mitotisis to forma allus ( mass o undifferentiaited totipotent vlles ) .

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32
Q

micropropagation 4

A

once a callus has fomred , it is divided to produce a larger number of smaller clumps of undifferentiited cells .

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33
Q

microprogaation 5

A

these small clumps , of cells are stimulated to grow ,, ddivide and differentiaite into different plant tissues .
-This is achieved by omving the cells to different rowth media .

-EACH medium , contins different ratios auxin and cytokin

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34
Q

micropropagation 6

A

once tiny plantelets have been formed , these are transferred to greenhosue to be grown in compost or soil and acclimatised to nromal growing palnts .

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35
Q

advantages of articial cloning

A

cloning is a reltive rapid method , of producing new plants comapred with growing plnts from seed .

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36
Q

advantages of artificial cloning 2

A

cloning can be carried ou where sexual reproduction is not possible .
-Plants , that have lost thier abilitiy to breed sexually , can be reproduced . for example commercially gorwn bananas , PLANTS THAT RE HARD TO GROW FROMS EED CAN BE REPRODUCED ,

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37
Q

advantages of artifical cloning 3

A

the plant selected will all be genetically idenitcal to the parent plant . The will therefore display the same desirable chaarcterisitcs , such as high yield resitnce to a common pest or disease or apartciular coour or flwoer .

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38
Q

advanatges of artificial clonin g 4

A

if the original plant had an unusual combination og characteristics due to sleective breeding or genetic ., modification , then this combination cn be retained without the risk of losign the combinaiton through sexual reproduction .

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39
Q

advantages of artifical cloning 5

A

the new plants are all uniform in thier phenotpes , which makes them easier to grow and harvest /

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40
Q

advanatges of artificial cloning 6

A

using the apical bud as an explant for tissue culture ensures the new plants are free from viruses .

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41
Q

disadvanatges of artificial cloning

A

tissue culture , is labour intensive

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42
Q

disadvantages of artifical cloning 2

A

it is expensive to set up the facilitites to perform tissue culture successfully .

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43
Q

disadvanatges of artificial cloning 3

A

tissue culture , can fail due to micorbial contmainaito

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44
Q

disadvanatages of articial cloning 4

A

all the cloned offspring , are geneticlly idenitcal and re therefore susceptivle to the sme pest nd or disease .

-CROPS grown in monocultures , allow rapid spread of a disease or pest betwen the closel planted crop plnts .

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45
Q

disadvantages of artificial cloning 5

A

there is no egentic variation excep tthat introudced by mutation .

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46
Q

what is embryo twinning

A

splitting an embryo to create two genetically identical embryos .

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47
Q

what is enucleeation

A

removal of the cells nucleus

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48
Q

somatic cell nuclear transfer

A

a technique that invovles transferring , rhe nucleus from a somatic cell to an egg ce; /

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49
Q

why do cells hve to b totipotent

A

such cells can dviid nd differentiite into all types of clel foun in the adult organissm . In animals the only truly totipoen cells are very earl embryo cells /

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50
Q

one reason why reproductive cloning can be usueful
ELITE FARM ANIMALS PRODUCED BY SELECTIVE BREEDING / AS or GM

A

for exmaple , a aprticulary goo didnivudal bull whoe vlaue is as a stud - supplying sperm for artifical insemination .

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51
Q

second reason why reproductive cloning can be useful

A

genetically modified animals , developed with unusual characerisitcs , for exmape , goats that produce spider silk in their milk and cows that rpoduce less methane .the

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52
Q

he two main rehxniques to achieve reproductive cloning

A

-emvyro twinnning
*CNT

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53
Q

embryo splitting

A

mammals , can produce idneital offspirngs , if an embryo veru early in development . This procss gives rise to an IVF .

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54
Q

IVF 1

A

A zygtote ffertilsied egg by ivf

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55
Q

IVF 2

A

the zygote , is alloed to divide by mitosis to form a small ball of cells .

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56
Q

IVF 3

A

The cells are separated and allowed to continue dividing .

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57
Q

IVF 4

A

each small mass of cells is placed into the uterus of a surrogate mother .

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58
Q

scnt 1

A

an egg is obtianed and its nucleus is removed known as enucleaiton .

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59
Q

scnt 2

A

a nromal body cell (somtic cell ) , from the adult to be clones is isoalted and may havve the nucelus removed .

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60
Q

scnt 3

A

the complete adult somatic cell or its nucelus fused witht he empty cell by applying an electric shock .

61
Q

scnt 4

A

the shock also triggers the egg cell to sttart feeloping though it had jut been fertilsied .

62
Q

scnt 5

A

the cell undegroes mitosis to produe a small ball of cell .

63
Q

scnt 6

A

the ogung embry is palce dinot the uterus of a surrogate mother .

64
Q

what is non reproductive clonin

A

non reproductive cloning is the production of cloned cells and tissues for purposes other thaan reproduction .

65
Q

therapetuci cloning
-new tisseus and orgns cna be grown as repalcement parts of people who are not well . - SKIN

A

SKIN CN BE grown iIBF , to ACT A GRFT for over burned areas .

66
Q

Therapeutic cloniing - cloned cells have been used to

A

repair damage to th spinal cord of a mouse and to restore the capabilit to produce insulin in the pancreas .

67
Q

therapeutic cloning - potneital to grow whole enw organs

A

to replace diseased ones

68
Q

why is tissues grown from own pateints cells be better

A

it will be geentically identical and o avoid rejection , which i a problem when transplanting doanted organs .

69
Q

cloned for scientific research

A

cloned genetically identical embryos can be used for scieniifc research into the ction of genes , that control , developemnt and fifferentiation .

-DUFFERENTTION .
-They can also be used to grow specific tissues or organs for use in test ont he effects of meidicnl durgs .

70
Q

arguments for artifical cloning (1)

A

can produce a whole herd of animals , with a high yield or shwoing an unusual combinaiton of charactersics (such as producing silk in their milk ) .

71
Q

arguments for artifical cloning (2)

A

produces genetically identical copies of very high vale individuls retaining the same chaacterisics ll

72
Q

arguments for artifical cloning (3)

A

using genertically idneitical embryos and tissues for scientific reserch allows the effects o egens an dhormones to be assessed with no interference from different genotypes .

73
Q

arguments for artifical cloning (4)

A

trsting medicinal drugs on cloned cells and tissues avoifd uding naimals or people for testing .

74
Q

arguments for artifical cloning (5)

A

cn prouce cells n tissues geenrticll identicl o he donor for use in repiring dme cused b diseae or accidnts .

75
Q

arguments for articial cloning (6)

A

individual from an endangered species can be cloned ot increase numbers .

76
Q

arguments against artifical cloning in animals (1)

A

lack of genetic variation may expose the herd to certain diseases or pests .
-Animals maybe produced with little regard for their welfare , which may have undesribale side effects such s meat rpucing .

77
Q

arguments gisnt artifical cloning in annimals (2)

A

sucess rate of adult cell cloning is very poor and the method is a lot mor expenisve , than conventional breeding . Cloned animals may be less ehalthy and have shorter lfie spans .

78
Q

arguments gisnt artifical cloning in annimals (3)

A

dodes not help incres egeenti diversit

79
Q

biotechnology

A

the use of living organisms or prts of living organisms in industrial processes . his could be to produce , food , durgs or other products .

80
Q

biotchenology in food - example an dorganims

A

ehtnaol in beer nd wine - yeast s
cabrondioxide to make bread rise - yeast s
lactic acid to mae chees eyoughot - lacotbacillus bacteir .

81
Q

biotechnology in pharmaceutical durgs

A

pencillin - pencillium fungus
insulin - gm bacteira

82
Q

biotechonoogy in enzymes

A

protease and lipase - bacteira
pectinase - aspergillus niger

83
Q

one advantage of using microrganisms in biotechnology (1)

A

microorgansimss are relatively cheap and eay to grow .

84
Q

second advantage of using microrgansims in bioechnology (2)

A

in most cases , the produciton of processes takes place a lower temps , tht woud be required to make the moelcuels by chemical engineering ,s ves fuel and reduced costs .

85
Q

third advanatage of using microrganisms

A

the production can tak eplce a normal amopsheirc pressue , which is safer than using , chmical reactions that may veryhigh for successful manufacutre o certian meoclues .

86
Q

what other organissms are used in biotechnology

A

genetically mdofiied mammlas , such a sheeps gaots cows , cn be used to produce useufl proiens .
-IN SOME MAMMALS , the proteins are icnorpte dinot the milka n cbn be eislyahrvested , GOATS have been gm to psses th eene for psider silk into their milk .

87
Q

other forms of biotechnology

A

gene technology
genegic mdoifciton
selecitve breeding

88
Q

how is youghurt created (1)

A

-Youghurt is miilk that hs undergone fermentation .
-BACTERIA converts lactose to lactic cid .
-the cidity dentures the milk protein cusign it to CAGULAE .

89
Q

how is youghurt crested (2)

A

the bacteria partially idgests the milk making it easy to digest . Fermentation also produces the flavours of characerisic to otoughurt .

-SOME BACTEIRA HEL TO IMPROVE DIGESITON OF LACTOSE .

90
Q

How is cheese created

A

milk is uauslaly pretreared with a culutre of bactiera hat can produce alctic acid from the lctose .

-Once its cifified the milk is mixed with rennit , hich is young in stomhc oung mammals

RENNIN COGAGUALED MILK PROTEINS INT HE PRESENCE OF CLCIUM IONS .

91
Q

cheese created (2)

A

resulting solid clled cird , is separated frpm the liquid component by cutting stirring and heaing . THE BACTERI , continue , to grow producing more lactic cid , CURD IS PRESSED INTO MOULDS .

92
Q

Cheese created (3)

A

treatmet , while making and pressing , the curd detemrines , charactersitics of cheee , Flavour , is determined the later irpenign and maturing processes . he

93
Q

how is baking

A

MIXING - the ingredient are mixed together throgouhly by enading this produces dough .

PRPOVING FERMENTING - DOGUH LEFT EM SO YEAST ESPIRED AAERBOCIALY TO PRODUCING CO2 .
COOKING - the risen dough is baked anya lcohol vaporated the cooking proces .

94
Q

alcoholic beverages

A

alcoholic bevarges are also the product o anaeboci respiration .
-WINE IS MADE USIN GRAPES THAT NTURLLY AHVE YEASTS ON SKIn w hen crushe dyeast uses thse usgars ot produce co 2 and alcohol .

95
Q

advantages of using microrganisms

A

production of protein canbe many times faster than tht o animal or plnt protein .

96
Q

advanatages of using micorogranisms 922)

A

the biomass producs has a very high protein content .

97
Q

advanatges of using micorgranisms

A

production can be increased and decreased accoding to demand . 3

98
Q

disadvantage of using microgransims 1

A

some people may not want to eat funa protein food that has been grown on waste .

99
Q

disadvanatges of using micororganism 2

A

isolaiton of the protein - the mciorganisms are grown in huge fermeneters and need t be isolated fromt he materil on which they grow .

100
Q

disadvanatges of using mciorogranisms

A

protein has to be purfiied to ensure it is not contaminared .

101
Q

what hpappens n fermenters

A

cp,cercial dur production usses large stianless steel contrinerscalled fermenters , in shich the growing coniions .

102
Q

why should TEMPERATURE BE CONTROLED in a fermenter

A

too hot and enzymes will be denatured , too cool nd growth will be limited .

103
Q

why should nutrients availbility be controlled in a fermenet

A

micorogranisms require nutrients to gro and synthesise the rpdocut . Sources of carbon , nitorgen minerals and vitamins needed .

104
Q

why should oxyygen availibity b controled in a fermeenter

A

most microrgansisms respire eroniclly .

105
Q

wh is pH controlled in a fermener

A

enzyme activity and hence growgh and syntheissi are affectd ny extreme of ph .

106
Q

why is concnetration of product monitored in a fermeneer

A

if a porduct is allwoe dot build up , it ma affect the syntheiss eprocess .

107
Q

a general diagram of idnustrial fermenter

A

shown on he page 253

108
Q

what is conitnous culture

A

some prodcuts are synthesised by the microrgansims during normal metabolism ,w ehen hey are actively growing. These are called primary metabolite , such prodctsare continually released from the cells and can ebe xtractec couslyf rom he fermenng borth . prevets opultionf rom being too dense , an i allows the mciorgansms to gow at a specfic rta .

109
Q

what is batch culture

A

other products are produced only when the cells are pace dunder stress , SUCH AS HIGH POPULAION DENSITY or limited nutreint VAVAIALABBILITY . THESE RE CALLED SEOCNDAEY WMRABOLITES ad are producrdd msotly uring thr stationary phe of rowth .

-HERE CULTURE IS SET UP WITH A LIMITED QUANTITY AND SPEICIFC ITME .

110
Q

what is asepsis and why is it important

A

asepsis is nsuring that sterilie conditon are miantianed . The nurient mediu would also support thr growht of unwated micoransims which owuld reduce produciton .

111
Q

what could unwnted micorgnsims in a fermenter do

A

compete with the cultured microorgansisms for nuterientsan space .
-reduce the yield of useful products
spoi producr prdce toxic chemicals

112
Q

asepsis stage one

A

the fermenter is run for six to eight days ,c ulture is then filtered to remove the cells .

113
Q

asepsis stage two

A

the antibiotic is precipitaed as crystals byt he addition of potassium compounds . anbtiotic myb e MODIFIEID by the ction of other micororgnsims or by chemical means

114
Q

asepsis stage three

A

the antibitoic is mixed wiht inert usbtanced and prepared for dmisnitration int abelt form as a syrup or as an injection .

115
Q

whaat is biroemediation

A

it is th euse of micoronsism to clen hte soil of undergoudn wter on polluted isted . THe organsim convert the toxic pollutnts to less harmful substanced .

116
Q
A
117
Q
A
118
Q

how cn bioremediaiton be used in unsuitbale condiotns

A

it cn add nturients such as molasses or pump oxyen or aerobic bactiera

119
Q

advanatages of bioremediiation

A

-uses natural ssytems
-less labour equipemnt is required
-tretmen tis ini stu
-fewer aste products
-les irsk of exposure to clen ip perosnnel

120
Q

Disadvantages of bioremedaition

A

HOWEVER BIOREMEIATION ONYSUTIBAE OFR CERTIAN PRODUCTS , HEAVY EMTL SUCH AS ADIU AND LEAD CNNOT BE RETE D.

121
Q

what is agar

A

a polysaccharide made of galactose obtined from seweed which i ued to thicken the meidum inot gel

122
Q

what is an aspetic technique

A

sterile gecnhiiqes used in cultuirng and mankpuating micorganisms .

123
Q

micorhansimss will grow on almost any material that provides the cabon compound for …

A

respiraiton and a souce of nirgen for protein synthesis.

124
Q

growing micorogrnsims on gaar plates invovl three main steps

A

-strilisation
inoculation
incubation

125
Q

how do you sterilise agar meidum and all equipent

A

autclave for 1 min , hight temp is ahcived for boilng ter .

126
Q

incooulation
neck of bottle contianing serilied nutrient gaar is passes thorgh lme
lid of pertri dish lfied slightlyt o aklow agar to e poured

A

… INOCULATION is in the intorudction of micorogrnais o the sterile meidum this can be ahiceved ina numeb way s
STREAKING
SEEDING
SPREADING

127
Q

What is incubarion

A

the petri dish must be labeleld an op taped ot the bootm using two stiep f adhie and palced in wamr enivronmtn , make surei dosnet dry out quickl .

128
Q

wha is a closed culture

A

it contians all the nutrients reuired for growth will udnergow popualiton eowh .

clsoed culture refers to popualtion inw hich all the ocndits are set t the start there is noe xchange in the xernal enviornemnt

129
Q

growth curve same as fermenter

A

pAGE for referebce to growth curve .

130
Q

LAG PHASE

A

-In the early part of population grotwh , the populaiton does not grow quickl .This is partly because the population is still small , but also because the organsimss are adjusting to hteir new enviornmnet .

-INVOLVING
TAKING UP WATER
CELL GROWTH
SWITCHING ON CERTIAN geens

131
Q

log (exponentiaal ) phase

A

i the log (exponential ) phase , the organsisms hve adjusted to their enviornemtn . They each ahve the enzymes needed to surivie . Each individiaul , has sufficent nutrients and space to grow raipdily nd reproduce . THE POPLATION DOUBLES IN SIZE WITH EAC GEENRATION once ebery - min

132
Q

the stationary phase

A

eventully the incresing numbers of orgnsims use up the nutrients and produce incresing amounts of wste products such as carbon dioide and other metabolites . The rate of population growth decines and the number of idnivudals ding increases untilt eh re reproduction rate eual the death rate .
THIS IS THE STATIONARY PHASE WHERE THERE IS NO POPULATION GORWT .

133
Q

Death (decline ) phase

A

the nutrients run out and the concentration , of waste productions may become lethal . MORE INDIVIDUALS die than are prouced and the poplations begins to fall, evenutallya ll the organsimss will die .

134
Q

what are primary metabolites

A

primary metbaolites produced udring the normal activities of the microoragnsims will be collected from a fermenter during the log pahse .
-In a fermenter the popultion is not kept in a clsoed culture , but conditions are maintained for optimal growth .

135
Q

what are secondary metabolites

A

secibdary metabolites , are produced in the stationry phase . The popultion must be ekpt in a closed culture , nd he metabolties can e collected t the end of the statioary pahe or during the decline pahe .

136
Q

immobilised enzyme

A

an enyzme hat is held i np place and no free to diffuse throug h the solution .

136
Q

Why are immobilised enzymes so useful in biotechnology

A

immobilised enzymes are taken out of suspension and held so that they do not mix freely with the suvstrate ,

137
Q

what is the advantage of immobilizing the enzyme (1)

A

-enzymes do not mix with the product , so extraction costs are loer
-the enzyme can be reused

137
Q

advantage of immobilizing enzymes (2)

A
  • a continous process is made esier as there are no cells rquringnutriend reproducing nd rleeasing waste products .
    -The enzymes are surrounded by immobilsing matri x which protects them from extreme conditions - so higher temps or a wider ph range can be used without causing denaturing .
138
Q

disadvanagtage of the immobilisd enzyme proess

A

setting it up is more expensive , and immobilised enzymes are usually less active than free enzymes making the process slower .

139
Q

one method used ot imobilise enzymes is ADSORPTION

A

Enzyme moelcules are bound to supporting surface b a combination of hydrophobic interactions and ionic links

-SUITABLE SURFAVES include clay , porous carbon , glass , beafd and resisns .

THE ENZYME MOELCULES ARE BOUND WITH THE ACTIVE SIE EXPOED AND CCESSIBLE TO THE SUBSTRAE .

-hOWEVER , THE ACTIVE SITE , may be slightly distored by the addditional interactions affecting enzyme activity .

140
Q

weakness of using adsopriton mehod

A

bonding forces are not laways stoenf and enyzms can become detached and leak into the reaction mixtre .

141
Q

another way to immobilise enzymes - COVALENT BONDING

A

enzyme moleucles are bonded to a supporting surface such as cly using a strong covalent bond . The enzymes are bonded using a CROSS-LINKING AGENT , which may also link them in a chian .

142
Q

drawback of covalent bonding as a method to immobilise enymes

A

the production of covalent bonding can be expensive and can distort the enzyme active site , reducing activity . However , the enzymes are much less likely to become detached and leak into the reaction mixture .

143
Q

what is entrapment a way to immobilise enzymes

A

enzyme molecules are trapped in a matrix that does not allow free movement . The enzyme molecules are unffected by entrapment and reamin full actice .
-However , the substratre moelcules must diffuse into the entrapment matirx and the product moelcules mus beable ot diffus eou .

144
Q

a way to immobils enezymes (2)

A

The method is thereofre suitable only for processes where the substrate and product molecles are relatively small . Calcium alginte beads are often used in schools to immobilise enxymes by entrpament . INDUSTRIAL PROCESSES MAY ALSO USE cellulose mesh .

145
Q

check figure 1 262

A

…

146
Q

what is membrane sepration

A

enzymes molecules are seprated from the reaction mixture yby a partially permeable membrane .
-AS IN entrapment the susbtrate and product moelcules must e small enoguh to pass through the partially permeable membrane b diffusion .
THIS CESS to rhe enzymes my limitt he reaction rate .

147
Q
A

A-level Biology (23 decks)

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