1.

(i)

plasmid cut by restriction enzyme; at specific sequence; same enzyme as used to cut (insulin) gene; sticky ends / described; ref. complementary sticky ends; ligase seals (sugar-phosphate) backbone / AW; credit any two from the following" # % ' antibiotic resistance (gene) introduced and sur$i$ors ha$e plasmid;

ma !

(ii)

fluorescent marker (gene) introduced and glo&ing bacteria ha$e plasmid; identify bacteria producing insulin using antibodies; %
[6]

2.

referring to pig insulin: ethical / religious( reasons; incompatibility / lack of tolerance / immune response; ora not e actly the same as / less effecti$e than( human insulin; ora referring to human insulin from bacteria: engineered insulin is cheaper; ora greater supply of engineered insulin; ora

#
[1]

3.

(i)

(penicillin) secondary metabolite ; produced at start of / during stationary phase / end of gro&th phase ; A log phase ref to production (at ma imum) &hen kept short of nutrients / nutrients depleting / factors limiting gro&th ; continuous culture maintains in( log / rapid gro&th( phase ; % ma

(ii)

to pro$ide respiratory substrate / energy ;

A for respiration

to maintain culture / keep culture ali$e / pre$ent (premature) death of culture ; (limited) maintains in stationary phase / pre$ents rapid gro&th ; A)* ; R glucose as carbon source % ma
[4]

The Henrietta Barnett School

4.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

genetic( testing / screening; for inherited disease / AW; (test to see if) indi$idual is carrier; premarital testing / predict if (potential) offspring may inherit the disease ; antenatal testing; ref to termination; embryo selection (to ensure embryo healthy) ; R selection of se (test for genes that contribute to) diseases that de$elop later in life ; those &ith genes gi$en( ad$ice to limit effects / counselling ; faster / earlier( diagnosis; de$elop more( effecti$e / efficient( drugs (to combat disease) ; drugs ha$e direct effect( on genes / protein made from specific gene code ; gene therapy / correct the base sequence of faulty gene ; economic implications / AW; A)*; e.g. ref. to method used / use of gene probes / biopsy A)*; allo&s targeting of drug treatment ! ma
[4]

5.

AA+,,, / adenine adenine thymine cytosine cytosine cytosine ; (first -)

6.

can fi nitrogen; does not deplete soil nitrogen / impro$es nitrogen content of soil (o$er time) ; allo&s culti$ation of poor soil; reduces use of fertilisers; higher yield; A)*; e.g. reduce contamination of en$ironment by fertilisers qualified cost ref. ref. leaching of nitrate

% ma
[2]

7.

(a)

odd number of sets of chromosomes / AW ; homologous pairs not formed ; A ref to difficulties in pairing during meiosis ; allow point if reference made to causing problems during meiosis does not form seeds ; ma %

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(b)

ref to( sterile conditions / aseptic techniques ; (small) piece of plant tissue remo$ed ; e plant ; or leaf remo$ed ; enzymes / cellulases / pectinases( to remo$e cell &all ; protoplasts formed ; gro&th on nutrient medium ; plant gro&th regulators / named gro&th regulator ; rooting ; incubation in light ; plantlets ; subdi$ide ; handling( medium / sterile soil ; A)* ; A)* ; e.g. remo$e &a from lea$es callus culture / mass of undifferentiated cells forms ref. au in to cytokinin ratio .urashige and /koog (. 0 /) medium further detail of culture method / aseptic technique ma 1 R hormones A take cuttings ref to named tissue ; e.g. meristem( a illary / (apical) buds

(c)

max 4 for either advantages many plants ; genetically identical ; (so) all ha$e desired( characteristics / genotypes / phenotypes ; no need for (artificial) selection ; can be obtained in short space of time / AW ; easy to( transport / store ; easy to genetically engineer ; disease / $irus( free ; disadvantages genetically identical( qualified in terms of disad$antage ; susceptible to disease ; loss in genetic di$ersity (as cloned plants are gro&n e clusi$ely) ; farmers ha$e to buy plants from suppliers / AW ; ref to economic problems for de$eloping countries ; e.g. start up costs patented property ; A ref to space sa$ing

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A)* ; A)* ; e.g. no quarantine required( ref. to cost qualified( not labour intensi$e (ad$antages)( genetically unstable (disad$antage) ma 1
[12]

The Henrietta Barnett School

8.

(a)

pro$ides o ygen for aerobic respiration ; any detail( e.g. o idati$e phosphorylation ; sterile to pre$ent contamination ; mi es fungus &ith substrate / pre$ents settling / bubbles help stirring / AW ; %

(b)

(i)

carbon 2 glucose / lactose ; nitrogen 2 amino acids / nitrate ions / ammonium ions / yeast e tract ; A corn steep liquor for either but not both %

(ii)

&ater is for( cooling / remo$ing e cess heat ; maintains( constant / optimum( temperature ; respiration produces heat ; &hich &ould( denature enzymes / kill cells ; heat also produced by( stirrer / motor ; ma ' % #

(iii)

&ill affect( enzyme action / metabolic rate ; A denature enzymes addition of( buffer / acid / alkali / base ; 3- hours ; X includes( rapid / e ponential / main( gro&th phase ; ora &hen primary products are made / penicillin is a secondary metabolic product ; e cess of nutrients in X or penicillin produced &hen nutrients( limited / depleted ;

(c)

(i) (ii)

'

(d)

filter (to remo$e fungus) ; fungus &ashed (to remo$e penicillin) ; continuous countercurrent / chemical e traction ; concentration ; addition of potassium ions ; precipitate crystals / (potassium) salts ; sol$ents used to purify penicillin ; A)* ; e.g. dried( some are chemically modified( 33.14 pure ma '

(e)

can genetically engineer microorganisms ; ref to risk of infection ; e.g. ,56 &ith 78 a$oids problem &ith( side effects / allergic effects ; A ref. to immune response large amount of product ; gro& microorganisms in small( area / $olume ; A less space required can be cultured any&here in &orld ; ethical ad$antages( qualified ;

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ref to cost qualified ; e.g. insulin uses cheaper feedstock (than for rearing pigs) A)* ; A)* ; e.g. high replication / gro&th rate e traction of 78 from brains slo& process ma !
[20]

9.

(a)

(i)

temperature ; concentration of( substrate / sugars / carbohydrates ; concentration of yeast ; p8 / carbon dio ide concentration ; o ygen a$ailability ; concentration of( alcohol / ethanol / to ic &aste ; A)* ; ma ' A ,9% # R $olumes / amounts R $olume / amount

(ii)

carbon dio ide ;

(b)

(i)

one mark for slow, fast, slow / nothing initial gas production slo&( ref to time ; rapid rate( ref to time ; little gas production( ref to time ; ref to actual $olumes ; any rate calculated ; ma !

(ii)

ref to (aerobic / anaerobic) respiration ; slow gas production transport of glucose into yeast cells takes time ; A absorbed / taken up by yeast detail ; e.g. ref to carriers rapid rate of respiration high substrate concentration in yeast cells ; rate slows substrate runs out ; or other factor(s) / named factor( affect the rate ; A)* ; e.g. increase in number of yeast cells increases rate of respiration( qualified ref to time taken for ad:ustment to conditions (in slo& production)

ma !

(c)

slower rate of respiration enzymes(s) to( metabolise / hydrolyse / digest / breakdo&n( maltose not present ; genes s&itched on ;

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time for enzymes to be synthesised ; ref to( membrane transport / ease of passing through membrane ; A)* ; e.g. facilitated diffusion ma %
[14]

The Henrietta Barnett School

10.

(i)

fe&er genetically engineered mosquitoes pass parasites across midgut ; A figures fe&er g e mosquitoes ha$e parasites in sali$ary glands ; A figures fe&er g e mosquitoes can infect (uninfected) mice ; A figures less good as vectors instead of all of first three points = only use of comparati$e figures ; ma '

(ii)

benefit one of follo&ing ; reduce use of( insecticide / drug safer than( insecticide / drug A)* ha!ard one of follo&ing ; parasite may de$elop resistance gene may pass to other species A)* ma #
[5]

ma #

11.

(i)

adding / using( &ater ; breaking( bond / ester bond (in molecule) ; A breakdo&n into smaller molecules %

(ii)

matri ( protects / stabilises( (immobilised) enzyme / lipase ; allow once so &ill function( at optimal rate / more efficiently (than soluble)( at higher temperature / !1 ;, ; A greater acti$ity / AW ref to soluble lipase begins to denature (reducing acti$ity) ; ora continues to &ork( at optimal rate / more efficiently( at lo&er p8 ; ref to presence of fatty acids changing p8 ; ref to ionic bonds breaking (in soluble lipase) ; ora A)* ; e.g. ref to industrial uses( ref to effect on < groups ma !
[6]

The Henrietta Barnett School

12.

(i) (ii)

attached to an insoluble material / AW ; (micro)encapsulation / (trapped) in alginate beads ; adsorption / stuck onto( e.g. collagen / clays / resin / (porous) glass ; cross linkage or co$alent / chemical bonding to( e.g. cellulose / collagen fibres ; gel entrapment / trapped inside gel e.g. silica (lattice / matri ) ; partially permeable membrane (polymer) microspheres ;

ma %

(iii)

urine can be processed / no problem of remo$ing urine / AW ; pure / drinkable / useable( &ater produced ; A &ater recycled space sa$ing / less &ater needs to be taken into space ; payload limit / &eight reduction / AW ; no need to take more enzymes into space / enzymes reusable ; A enzymes reco$erable no problem in separating enzyme from products / product not contaminated ; ref to longer shelf-life of enzyme ; A)* ; e.g. larger surface area of enzyme e posed( more stable at e tremes( ref to ease of use (of bioreactor) ma '
[6]

13.

(i)

ref to( r6=A / recombinant 6=A ; restriction enzyme(s) ; cut 6=A at specific site(s) ; detail site(s) ; ref to $iral 6=A and( human 6=A / 6=A of gene ; ref to sticky ends ; complementary binding ; detail of binding ; A > + / , > 7 / hydrogen bonds ligase to seal ?nicks@ in (sugar-phosphate) backbone ; ma !

(ii)

has effect &hen added to genome ; not masked ; no need to( remo$e / inacti$ate( recessi$e / mutant( allele ; ma %
[6]

14.

(i) (ii)

6=A from t&o different sources ; combined / :oined / AW ; restriction enzymes cut 6=A ; at specific sites ; detail of sites ; %

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may gi$e sticky ends ; complementary sticky ends :oin ; terminal transferase / enzyme( adds sticky ends ; ligase :oins( gaps / nicks ; ma '
[5]

The Henrietta Barnett School

10

15.

(a)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

pre$ent( self-pollination / un&anted pollination( of flo&ers ; detail of pre$ention ; cross-pollinate t&o $arieties ; A crossed / mated / hybridised detail pollination ; isolate( plants / flo&ers ; collect seeds and so& ; in high salt concentration ; select plants( &hich sur$i$e / can tolerate( high concentration ; and ha$e large( tasty tomatoes ; interbreed these plants ; repeat selection ; ref many generations ; cross &ith $ariety &ith large tomatoes to impro$e size ; cross &ith $ariety &ith good fla$our to impro$e taste ; ref backcrossing &ith original $ariety for salt tolerance ; A)* ; A)* ; e.g. ref background genes / hybrid $igour / heritability / effect on $igour / ref setting up pure-breeding initial lines QWC legible text with acc !ate "#elli$g% # $ct ati&$ a$' g!a((a! ; # ma A

(b)

(i)

acti$e transport ; (energy from)( A+* / respiration ; against concentration gradient ; ref binding site for ion / AW ; ref change of shape of protein ; ma '

(ii)

7B quick(er) / /C slo&(er) ; (tolerance) in one generation ($. many generations) ; ref one gene / rest of genome unaltered ($. hybridisation) ; background genes intact ($. need for backcrossing) ; different $arieties engineered for different conditions ; no problem re interbreeding ; can select( transporter system / AW( / from( another species / named ta on ; can select( transporter system / AW( / for ma imum efficiency ; A)* ; ma '
[15]

The Henrietta Barnett School

11

16.

an iety about (future) health / may not &ant to kno& / AW; many diseases &e can test for ha$e no treatments ; discrimination by employers; discrimination by( insurance companies / banks; reliability of tests in question; A false( positi$e / negati$e( result e ample of disease gi$en in conte t; cost to( =8/ / go$ernment; rich people can benefit / poor &ill not benefit ; A)*;; e.g. moral issues associated &ith embryo selection eugenics parents feelings to&ards child presence of allele may not cause disease / ref to multifactorial diseases ref to storage of data and freedom of information / in$asion of pri$acy / question of paternity R ?playing 7od@ / cloning ! ma
[4]

17.

(i) (ii)

restriction (enzyme) / endonuclease; this may be answered in the context of inserting into a plasmid" cut 6=A &ith restriction enzyme ; ref to sticky ends; complementary; base pairs / ,,, and 777 / , pairing &ith 7 / alternati$e ; (6=A) ligase / ligation; ref to bonding / AW; e.g. hydrogen or phosphodiester / sugar-phosphate A)*; e.g. add sticky ends to blunt ends cut both at the same place

' ma

(iii)

codes for % protein / polypeptide / enzyme; A ref to( protein synthesis / transcription / translation (enzyme) catalyses / causes % condensation / formation of glycosidic bonds / reaction (bet&een % mannose / sugars); %
[6]

The Henrietta Barnett School

12

18.

cheaper; ref to compatibility / less chance of re:ection / fe&er side effects ; stated ethical issue; e.g. don@t need to kill animals / remo$es religious ob:ections ref to contamination / easier to purify / ref to disease ; consistent quality; more effecti$e (as human in origin); production le$el can meet demand / reliability of supply / faster production ; ignore greater production

% ma
[2]

19.

(a)

(i) (ii) (iii)

amylase ; glycosidic ; alpha / D ; encapsulation / trapped in alginate beads ; adsorption or stuck onto( collagen / clays / resins ; cross linkage or co$alent / chemical bonding to( cellulose (fibres) ; gel entrapment / trapped in silica gel ; partially permeable membrane microspheres ; < glucosidic

# # #

(b)

(i)

ma %

(ii)

does not mi &ith / does not contaminate / stays separate from( the product ; ref to( no / less / easier( do&nstream processing ; reco$erable / not lost during processing ; reusable / cost effecti$e ; matri stabilises / protects the enzyme ; so acti$ity not affected by changes in( temperature / p8 or run at a high temperature / &ider range of p8 ; longer( use / shelf-life ; so suitable for continuous culture / cost effecti$e / greater yield ; A)* ; points can interchange if valid ma !

(c)

not necessary to start &ith a pure enzyme ; keeps the enzyme a&ay from o ygen ; more enzymes in$ol$ed ; cell produces enzymes ; A)* ; e.g. enzyme(s) may be( e pensi$e / difficult to isolate simultaneous processes can occur ma %
[11]

The Henrietta Barnett School

13

20.

(a)

(i) (ii)

penicillin ;

A other named antibiotic

(comple organic molecules) produced after / not produced during( the (log / rapid / main) gro&th phase ; not essential for normal( cell gro&th / reproduction ; ma # # batch / fed batch ; nutrients only added at start ; short / rapid( gro&th phase ; required product made( during stationary phase / late in life cycle ; ora R death phase shortage / depletion of( nutrients / named nutrients ; cell di$ision / reproduction( no longer occurring ; ref to addition of( glucose / lactose( at inter$als (to a$oid death of culture) ; ma %

(iii)

(b)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

air pressure &ill push the medium into the culture $essel ; medium / nutrients( added to the culture at a constant rate / AW ; algae / cells / #hlorella( remo$ed / har$ested( from the sample port ; at the same rate as / to match( the nutrients added ; so $olume in fermenter remains constant ; remo$al of( &aste / to ic products ; that could affect( gro&th / reproduction ; (cells kept in) e ponential / log / rapid / main( gro&th phase ; algae are photosynthetic ; light energy required ; ref to use of fluorescent light to a$oid o$erheating ; ref to monitoring temperature ; ref to optimum conditions ; A ?conditions for ma imum gro&th@ air bubbles to mi culture &ith nutrients / AW ; air bubbles to allo& algae to get sufficient light ; air bubbles pro$ide o ygen for (aerobic) respiration ; and ,9% for photosynthesis ; air flo&ing into the culture $essel flo&s out through an outflo& tube ; pre$enting build-up of pressure ; A)* ; e.g. sampling to check for mass of #hlorella ma -

The Henrietta Barnett School

14

(c)
difficulty maintaining a constant temperature ; one mark for ref to difficulty of difficulty maintaining a constant p8 ; controlling en$ironmental factors

heating / cooling( qualified ; foaming ; blocking of( inlet / outlet( tubes ; difficulties &ith( mi ing / stirring ; contamination / keeping it sterile ; conditions need to be continuously monitored ; nutrient requirements may change ; A)* ; A)* ; e.g. algal gro&th on glass difficulties in pro$iding sufficient light errors lead to loss of se$eral days production of #hlorella ma !
[15]

21.

(a)

plasmid $%& nucleotides / sugar E phosphate E base ; ! different subunits ; phosphodiester bonds ; A phosphoester contains * ; double-stranded / double heli ; circular ; A)* ; e.g. role of 8 bonds

protein amino acids ; %F different subunits ; peptide bonds / polypeptide ; contains / / disulphide bonds ; may ha$e !G structure ; ref to( %G / 'G( structure / AW ; ' ma #

(b)

(i) (ii)

stimulates( immune response / production of antibodies / + or C cells ; stimulate( cell-mediated immunity / + cells ; antigen( remains in body longer / continuously produced ; antigens in blood only stimulate( humoral immune system / C cells ; antigens (in blood) lost in urine / broken do&n in li$er ; ref to .8, ; # ma

(c)

(i)

binds <=A polymerase ; allo&s( transcription / production of m<=A ; s&itches gene on / allo&s gene e pression ; % ma

(ii)

(protect against) more than one( strain / disease / pathogen / AW ; stronger immune response ; less likely mutant form &ill escape immune response / AW ;

The Henrietta Barnett School

15

A)* ; cheaper / reduces number of $accinations (iii) 7olgi modifies protein / polypeptide / AW ; forms glycoproteins / add sugars or carbohydrate ; 7olgi forms $esicles ; incorporated into cell membrane ; R e ocytosis A)* ; (d) cells that take up $%& vaccine might 1 2 3 4 5 6 7 8 function less &ell ; be killed by immune system / trigger auto-immune response ; ha$e genes disrupted / mutation ; ne& gene might be inherited / AW ; plasmid could enter bacteria ; superbug / create ne& disease / AW ; effects unkno&n / ne& technology / no human trials ; A)* ; ref ethics( ref irre$ersible

% ma

% ma

' ma
[14]

22.

increase in use of( 7. crop / 7B crop / Ct cotton ; no / less( insecticide needed ; reduced number of cases of pesticide poisoning ; ref to figures (e.g. by !.!) ; reduced cost (insecticide) ; ref to figures (e.g. by F.-% H/I kg-# / J #.'A) ; ref to limitations of sur$ey ; A)* ; A re$erse arguments ma !
[4]

23.

(a)

(i)

gradual process / AW ; to impro$e traits ; to achie$e homozygosity / AW ; best in each generation interbred ; ref to artificial selection ; ref to se$eral traits in$ol$ed / may be( additi$e / polygenic ; ma %

(ii)

ref to mitosis ; chromosomes replicated ; failure of( spindle / cell di$ision ; ma %

The Henrietta Barnett School

colchicine / other method ; (iii) self-pollination pre$ented ; pollination by foreign pollen pre$ented ; pollen transfer ; practical detail ; (i$) 'n ; meiosis fails ; ref to( synapsis / homologous pairs ; ma % ma %

The Henrietta Barnett School

17

(b)

(i)

sterile e plant ; sterile nutrient medium ; ref to plant gro&th regulators ; callus ; subdi$ided ; medium &ith different plant gro&th regulators ; plantlets / embryoids ; hardening medium / sterile soil ; A)* ; e.g. appropriate plant gro&th regulators ma 1

(ii)

callus can be di$ided ; large numbers of identical plants ; in short time ; bulk up sterile hybrid ; bulk up master hybrid lines ; no need for making more !n ; ma %
[15]

A clone

24.

(i)

type of starch ; concentration of( starch / suspension ; $olume of( starch / suspension ; ref to flo& rate ; size of beads ; temperature ; A number / mass / $olume( of beads in column R amount R amount

length / diameter( of column ; yeast concentration ; p8 ; A)* ; e.g. age of culture (ii) add Cenedict@s (reagent) and( boil / heat ; A ,u/9! in alkaline solution different( densities / colours (of precipitates) formed ; A turbidities use of a colorimeter in correct conte t ; A filtering and &eighing precipitate )R use of ,linisti / 6iasti (strips) ; different colours obtained ; colour compared to chart ; accept other valid methods e"g" reference to use of biosensors % ma ' ma

The Henrietta Barnett School

18

(iii)

agree not all yeast cells successfully entrapped / AW ; (in product) yeast cells( respiring / metabolising / using sugar as an energy source ; (so) lo&er le$els of sugar (in product) ; not agree yeast cells( entrapped (in beads) / immobilised( so product not contaminated / yeast not present to affect product ; yeast cells unable to pass through( glass &ool / filter ; only $ery lo& numbers of yeast cells (so unlikely to ha$e great effect) ; % ma
[7]

25.

any three acceptable e"g" disease / $irus( free ; genetically identical / clone ; maintain( fa$ourable characteristics / ad$antageous phenotypes ; faster method ; produces many plants ; allo&s long-term storage of plant tissue ; easily genetically manipulated / e ample of genetic manipulation ; easier e change bet&een countries as no quarantine ; enables optimal production of useful secondary products (e.g. codeine from poppy) ; no e ternal en$ironmental influences ; no influence of seasonal $ariation ; A)* ; e.g. use for( sterile / infertile( plants( A)* ; named e ample of ad$antageous phenotype e.g. gro& more $igorously use for rare or endangered plants rele$ant e ample of genetic manipulation ' ma
[3]

The Henrietta Barnett School

19

26. 1 2 3 4 5 6 7 5 6 7 8 9 10 11 12 13 14 15 16

answers referring to insulin production can also be credited in mp ',(,4 )scherichia coli ; genetic engineering amino acid sequence (of 878)( kno&n / analysed ; gene coding for 878 synthesised ; using( triplet code / genetic code ; *+ m<=A (coding for insulin) from beta cells ; use re$erse transcriptase ; synthesise c6=A ; plasmid ($ector) ; cut using restriction (endonuclease) enzyme ; ref to gene and plasmid mi ed &ith (6=A) ligase ; (recombinant) plasmid introduced into( bacterium / bacteria ; large scale production genetically engineered / recombinant bacteria ; gro&n in fermenter / fermentation( qualified ; reproduce / replicate / multiply / undergo binary fission / form a clone / large numbers / millions of bacteria / gene cloning ; idea of gene e pression / transcription and translation( for 878( synthesis / production ; A insulin when relevant do&nstream processing ; separation / purification( of gro&th hormone ; A)* ; A insulin when relevant A)* ; e.g. ref to screening using antibiotic resistance markers scaling up to determine optimum operating conditions bacteria killed and separated (from proteins) by centrifugation gro&th hormone separated from other( proteins / molecules (product separated by) large scale chromatography / ultrafiltration other detail of fermentation e.g. p8 1.1 2 A.F( temperature %F 2 !1 G,( aeration( glucose doubling time %F minutes QWC clea!% well &!ga$i"e' with "#eciali"t te!(" ; any three, used in context, from amino acid sequence (beta cells for insulin) / triplet (m<=A for insulin) / genetic code (re$erse transcriptase for insulin)( plasmid( $ector( restriction enzyme( ligase( recombinant( genetically engineered( binary fission( clone( transcription( translation( do&nstream processing( screening( antibiotic resistance markers( centrifugation
[7]

A )" coli ' ma

AW ! ma

- ma #

The Henrietta Barnett School

20

The Henrietta Barnett School

21

27.

(a)

r6=A > 6=A from t&o sources ; both 6=As cut &ith( restriction enzyme / named restriction enzyme ; gi$ing sticky ends ; or gi$ing blunt ends to &hich sticky ends added ; complementary binding of sticky ends ; 8 bonds / e.g. A to + / e.g. , to 7 ; nicks in (sugar-phosphate) backbone sealed by ligase ; ' ma

(b)

percentage / proportion( of( muscle fibres &ith central nuclei / dying muscle fibres( increases in control &ith time ; percentage / proportion( of( muscle fibres &ith central nuclei / dying muscle fibres( reduced by treatment ; ref to comparati$e figures &ith percentages and day ; '

The Henrietta Barnett School

22

(c)

advantages 1 2 3 4 5 6 7 8 9 can identify presence of disorder ; remo$es uncertainty ; allo&s early treatment ; &hich may impro$e( life e pectancy / quality of life ; A a$oid unncessary suffering allo&s( informed choice about ha$ing children / planning healthy family ; allo&s K)L and( embryo screening / preimplantation genetic diagnosis (*76) ; allo&s fetal testing and termination ; choice( re donation / adoption ; A)* ; e.g. detail of donation" AK(6) / egg donation / embryo donation (axi( ( 5 &$ a'*a$tage" disadvantages 10 11 12 13 14 15 16 17 18 false( positi$es / negati$es ; may not be test for all mutations ; only small number tests a$ailable / not a$ailable for all conditions ; simple presence may not result in condition ; confirmed presence gi$es stress / fear ; problem re( telling / testing( rest of family ; discrimination by( employers / insurers ; ethics of termination ; A)* ; e.g. detail of problem of test( risk of test procedure( diagnosis and elimination rather than treatment( increase in( intolerance / discrimination( of disabled( ?designer@ problem (axi( ( 5 &$ 'i"a'*a$tage" A ma QWC clea! well &!ga$i"e' "i$g "#eciali"t te!("; must include both advantages and disadvantages and two terms such as life e pectancy( quality of life( K)L( *76( *78( AK(6)( amniocentesis( ,)/( karyotype( false positi$e( false negati$e
[15]

The Henrietta Barnett School

23

28.

award marks if diagram clearly annotated reser$oir for storage of nutrients ; ref to method for addition of nutrients and remo$al( of &aste / products ; A substrate ref to more detail of( nutrient addition / product remo$al( at a constant rate / continually / throughout fermentation period ; idea of rate of product remo$al equal to addition of nutrients ; A keep $olume constant use of probes / sensors / monitors ; A thermometer (for temperature) (to monitor) any t&o of( temperature / p8 / o ygen le$els ; method to maintain p8 e.g. use of buffers( tube to add acid / alkali ; addition of antifoam ; ref. to need to maintain sterility (to a$oid contamination) ; method to maintain constant temperature e.g. (thermostatically-controlled) &ater bath( cooling :acket ; R heat e changer A)* ; e.g. use of stirrer( method to a$oid( clumping of cells / blocking of inlet or outlet pipe(s) ! ma
[4]

29.

(a)

a$oid attracting a mate of a different species ; ora ensure reproducti$e isolation ; # ma # # ma

(b)

(i) (ii)

diffusion ; so that they do not recei$e o ygen constantly ; there are mitochondria bet&een them and the cell surface ;

(c)

mitochondria / aerobic respiration / o idati$e phosphorylation( inhibited only briefly ; o ygen concentration decreases again ; pre$enting( action of luciferase / production of light ; each flash short ; ora e.g. so not continuously lit A)* ; acti$e transport ; A e.g. =aE/ME pump protein synthesis ; synthesis of named substance ; mo$ement of organelles ; phosphorylation of glucose ; A)* ; ; ; e.g. transcription( translation( anabolic reaction % ma

(d)

The Henrietta Barnett School

24

R respiration( 6=A replication( chromosome mo$ement( mitosis

' ma

The Henrietta Barnett School

25

(e)

cells / membranes( damaged / disrupted ; nitrous o ide released ; mitochondria stop using o ygen ; o ygen( allo&s light production / reaches light-producing organelles ; in unlimited quantities / continuously( so light is brighter ; respiration / o idati$e phosphorylation( ceases ; no more( A+* / =A68% ; luciferin( synthesis / regeneration( stops ; A)* ; ' ma # #
[13]

(f) (g)

li$e bacteria( respire / produce A+* ; ora m<=A (coding for luciferase) ; A 6=A

30.

(i)

max for meaning of term attached to an insoluble material / AW; max ' for description (micro)encapsulation / (trapped) in alginate beads; adsorption / stuck onto( collagen / clays / resin / (porous) glass; cross linkage / co$alent / chemical( bonding to( cellulose / collagen fibres; gel entrapment / trapped inside gel e.g. silica (lattice / matri ); partially permeable membrane (polymer) microspheres;

'

(ii)

any three from the following" urine can be processed / no problem of remo$ing urine / AW; pure / drinkable / useable( &ater produced; A &ater recycled space sa$ing / less &ater needs to be taken into space; payload limit / &eight reduction / AW; no problem in separating enzyme from products / product not contaminated; ref. to longer shelf-life of enzyme; no need to take more enzymes into space / enzymes reusable ; A enzymes reco$erable A)*; e.g. larger surface area of enzyme e posed( more stable at e tremes( ref. to ease of use (of bioreactor)

'
[6]

The Henrietta Barnett School

26

31.

(a)

(i)

# % ' ! 1 N A 3 #F

mutation ; random / spontaneous / chance / pre-e isting ; natural selection ; drug / insecticide( is( selecti$e agent / selecti$e pressure ; resistants ha$e selecti$e ad$antage ; resistants sur$i$e / susceptibles die ; pass( allele / mutation( to offspring ; R gene / resistance allele frequency increases ; rapid because( multiplicati$e phase / short generation time / large numbers offspring / many breeding sites ; ma 1

(ii)

,lasmodium inside( li$er cell / red blood cell ; antibodies cannot reach target / cannot be detected by immune system ; large genome ; antigenic $ariation / AW ; $ariation from meiosis ; detail ; e.g. independent assortment / crossing o$er parasite s&itches bet&een different $ersions of proteins ; ref var gene ; ma ' marks in pairs - one pair only mutation ; &ith lack of production ; examples in, promoter / on switch . so not transcribed . to give premature stop codon . so, no useful / shortened, product . deletion . with loss of allele / different product . frameshift . so, different / no useful, m+%& / product . in initiation codon . so m+%& not translated . &/, mutation . &/, lack of production ;

(b)

(i)

ma %

(ii)

marks in pairs - one pair only no( membrane receptor / AW ; so no( binding / internalisation ; no( channel / carrier / pump ; so lack of essential( nutrient / ion ; do not multiply in li$er ; so not a$ailable to infect red blood cells ; A)* protein ; problem ;

ma %

The Henrietta Barnett School

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(c)

#FF4 protection &ith % boosters ; irrespecti$e of dosage ; NF4 &ith # booster ; no e$idence &ith 1F FFF &hether &orks &ith one booster ; ref to memory cells ; needs large numbers of parasite / ref #F FFF ' ; safe / &ill not cause disease / does not kill mice ; might mutate back to &ild type ; can infect li$er cells e$en if no further de$elopment ; may need drug to remo$e from li$er ; data relates only to mice / may not be applicable to humans ; A)* ; e.g. no data comparing results &ith standard antigenic (AW) $accine

ma '
[15]

32.

(a)

(i)

t&o recessi$e alleles/homozygous recessi$e/t&o of allele %; no( normal dominant/allele #; homozygous same allele as affected child; deletion remo$es base pairs; shorter/lighter( pieces of 6=A mo$e further in electrophoresis; to&ards anode; so allele %( shorter/lighter( than allele #;

(ii)

ma ' #
[6]

(b)

F.%1/%14/# in !;

33.

(a)

m<=A and its complementary <=A bind together ; hydrogen bonding ; A to H and , to 7 ; R ?+@ double stranded <=A / duple <=A ; cannot bind to ribosome ; t<=A cannot bind ; cannot be translated / AW; ref to( <=A interference / <=Ai ; ! ma

(b)

(i)

theobromine content( reduced / appro imately hal$ed ; no significant difference bet&een short and long lengths of <=A ; caffeine content reduced ; to half by short lengths of <=A ; A figures to about a third by long lengths of <=A ; A figures ' ma #

(ii)

(re caffeine) greater chance of pairing longer length &ith m<=A ; A)* ;

The Henrietta Barnett School

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(iii)

e plant of meristematic / cambium / totipotent / pluripotent( cells / tissue ; e plant (surface) sterilised / sterile nutrient ; appropriate hormone to stimulate( mitosis / di$ision ; callus formed ; subdi$ided ; appropriate hormone to stimulate differentiation ; plantlet formed ; hardening medium / sterile soil ! ma

(i$)

genetically identical ; genotype does not affect result ; easily genetically engineered ; plants deri$ed from it identically genetically engineered / AW ; large numbers easily obtained ; early stages compact ; so easily kept in identical conditions ;
[15]

' ma

34.

# % ' ! 1 N A 3 #F ## #% #' #! #1

restriction enzyme to cut gene from genome ; and( plasmid / artificial chromosome / 6=A of $ector ; same restriction enzyme ; if cut &ith sticky ends then :oin ; if cut &ith blunt ends then( sticky ends / nucleotides( added ; R bases &ith , bases one end and 7 bases other ; requires terminal transferase ; (6=A) ligase needed to seal nicks in 6=A backbone ; ref to :oin phosphate - sugar / adds phosphate ; 6=A may be produced by re$erse transcriptase ; from m<=A ; single strand made double stranded by 6=A polymerase ; &anted 6=A replicated by polymerase chain reaction (*,<) ; using( 6=A polymerase &ith high optimum temperature / 0a1 polymerase ; A)* ; QWC + clea!% well+&!ga$i"e' a$"we! "i$g "#eciali"t te!(" ; award 23# mark if three of the following are used endonuclease terminal transferase re$erse transcriptase (6=A) ligase 6=A polymerase *,< correct use of nucleotide and base sticky ends blunt ends

ma A #

The Henrietta Barnett School

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[9]

35.

(i)

! - - base pairs ; palindromic / AW ; specific sequence ; yes( same sticky ends / sticky ends sho&n ; 7A+, / ,+A7 complementary (bases) ; hydrogen bond ; A &ith + ; , &ith 7 ; t&o correct cuts ; G| A T T C A G A A T T T C G| A A T C C T A A |G T C T T A A A G C T T A |G

ma %

(ii)

ma '

(iii)

#
[6]

36.

(i) (ii)

adding / using( &ater to break( bond / ester bond( (in molecule); A breakdo&n into smaller molecules matri ( protects / stabilises( enzyme / lipase; functions( at optimal rate / more efficiently( at higher temperature / !1 ;,; A greater activity / &3 ref. to soluble lipase begins to denature (reducing acti$ity); ora functions( at optimal rate / more efficiently( at lo&er p8; ref. to presence of fatty acids changing p8; ref. to ionic bonds breaking (in soluble lipase) ; ora A)* ; e.g. ref to industrial uses ref to effect on < groups

ma !
[5]

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37.

(a)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

gene bank ; ref to &ild type ; maintain genetic di$ersity ; ref to( loss of alleles / genetic erosion ; may ha$e appropriate trait for breeding ; for future use ; requirements of breeders change ; in case( climate change / different conditions ; ref to( temperature / global &arming ; ref to( p8 tolerance / acid rain ; as yet unkno&n traits may be useful ; in case other named change ; may lose trait if interbred ; may form part of( food &eb / community ; that cannot be replaced ; adapted for( habitat / niche ; hybrids less &ell adapted ; ref to e tinction ; A)* ; e.g. need to maintain population for leisure fishing A)* ; QWC legible text with acc !ate "#elli$g% # $ct ati&$ a$' g!a((a!; A ma #

(b)

(i)

enzyme from bacterium ; break do&n 6=A of in$ading (bacterio)phages ; ref to specific site of 6=A ; detail of site (! - - bp / palindromic) ; cut 6=A ; lea$ing blunt ends ; or sticky ends ; ' ma

(ii)

crucian carp # (thick) band in correct position (see diagram) ; hybrid goldfish x common carp ' (thin) bands in correct position ; hybrid common carp x crucian carp ' (thin) bands in correct position ; '
h y b r id c o m m o n c a rp x c r u c ia n c a r p

g o ld fis h

c o m m o n c a rp

c r u c ia n c a r p

h y b r id g o ld fis h x c r u c ia n c a r p

h y b r id g o ld fis h x c o m m o n c a rp

[15]

The Henrietta Barnett School

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The Henrietta Barnett School

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38. # % ' ! 1 N

tissue meristematic ; undifferentiated / totipotent / able to de$elop into any cell type / unspecialised ; (cells) can still di$ide / undergo mitosis ; $irus free ; sterilising agent aseptic technique ; pre$ent( gro&th of / contamination by( bacteria / fungi ; could o$er&helm / gro& faster than / compete &ith( plant tissue ; A AW

max '

max '

cytokinins, auxins A plant gro&th( !eg lat&! , #!&(&te! , h&!(&$e ; 3 cytokinins stimulate( shoot / stem( gro&th / many branches ; #F au ins stimulate gro&th of( root / root hairs ; ## #% #' #!

max '

magnesium, nitrate ions, sucrose magnesium for( chlorophyll / photosynthesis ; nitrate (ions) needed for( protein / enzyme / chlorophyll / named chemical ; sucrose con$erted to( glucose / fructose / monosaccharide ; used in( respiration / release energy ; max ( further detail e.g. cytokinins stimulate cell di$ision no $ascular tissue therefore disease free - ma #

#1 A)* ; e.g.

QWC clea! well &!ga$i"e' "i$g "#eciali"t te!(" ; award 23# mark if three of the following terms are given in correct context meristematic undifferentiated totipotent mitosis aseptic contamination regulator promoter hormone chlorophyll photosynthesis respiration

[7]

39.

(a)

(i)

co& supero$ulated ; treated &ith( hormone / L/8 / named proprietary brand ; &ashed out of o$iduct (A uterus) / collected from o$ary ; detail &ashing ; detail collection ; ref to mitochondrial 6=A ; detail ; e.g. circular / self-replicating mitochondria in cytoplasts fused &ith darted buffalo cell ; A organelle

ma '

(ii)

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embryo has mi ture of buffalo and co& mitochondria ; nuclear / chromosomal( 6=A is buffalo ; ref to bacterial contamination ; (iii) for correct phase of cycle ; ref to synchronisation ; to prepare uterus for (implantation of) embryo ; ref to increased thickness of uterine lining ; ref to increased $ascularisation of uterine lining ;

ma %

ma '

(b)

increases rate of reproduction ; does not require species@ eggs ; so does not require fertile female ; does not require female for pregnancy / uses surrogate ; female not put at risk in( tra$el / mating / pregnancy ; successfully formed embryo can be( subdi$ided / cloned ; can use adult cells from all e isting animals to maintain di$ersity ; sperm bank ; oocytes / eggs ; 4gametes5 > # mark only embryos ; tissue ; zoo / reser$e / game park ;

ma !

(c)

ma '
[15]

40.

max 7 for the process of genetic engineering max 2 for the advantages 1 2 identify / find( gene (for insulin) / length of 6=A coding for insulin; obtain / isolate / e tract( gene / length of 6=A (for insulin); obtain / isolate / e tract( m<=A (for insulin); restriction enzyme / named e.g.; re$erse transcriptase; cut plasmid; cut plasmid; use same restriction enzyme; use restriction enzyme / named e.g.;

3 4 5

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6 7 8 9 10 11 12 13 14 15

ref to( complementary ends / sticky ends / described; insert( gene / AW( into plasmid; recombinant 6=A; plasmid uptake by bacteria; identify those bacteria that ha$e taken up the plasmid; pro$ide &ith( ra& materials / nutrients; fermenter / bioreactor; bacteria produce insulin; e tract and purify / do&nstream processing; A)*; e.g.. detail of uptake by bacteria method of identifying those that took up plasmid *,< ligase 6 max greater / faster( production o$ercomes ethical problem described less risk of disease less risk of( re:ection / side effects human insulin so more effecti$e

16 17

ad$antage #; e.g. more reliable supply ad$antage %;

A ma

QWC clea!% well &!ga$i"e' "i$g "#eciali"t te!("; award 23# mark if four of the following are used gene restriction enzyme named e.g. of a restriction enzyme re$erse transcriptase fermenter / bioreactor plasmid complementary sticky end recombinant 6=A

[9]

41.

(i) (ii)

restriction (enzyme) / endonuclease; A named e.g. (6=A) ligase;

# #
[2]

42.

(i)

endonuclease; cuts 6=A; &ith sticky or blunt ends; at( palindromic/AW/specific/! to - base pair/restriction( site; from bacteria; for cutting ?phage 6=A; % sources 6=A; ref. sticky ends;

ma '

(ii)

The Henrietta Barnett School

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complementary binding; 8-bonds bet&een bases; A to + and , to 7; nicks in sugar-phosphate backbone sealed/AW; by ligase;

ma !
[7]

43.

(i)

indicates the range of results; on either side of the mean; indicates( $ariability/(standard) de$iation/(standard) error; indicates if data sets significantly different; no/small( increase/figs. quoted; lag phase; ad:ust to conditions/detail of ad:ustment; produce enzymes; A)*; more rapid gro&th in non-deficient cells/ora; figures in support from both a es of graph; lo& ribose in 7-*6 deficient cells/ora; less a$ailable to( parasites/,lasmodium; less production of <=A/ribonucleotides; less a$ailable for transcription; inhibited protein synthesis; less protein a$ailable for( reproduction/gro&th/cell di$ision;

% ma

(ii)

% ma

(iii)

! ma
[8]

44.

stated ad$antage; detail; e.g. particular character 7not whole phenotype8/can alter one trait only 7without affecting background genes8/can add allele from different taxon with which breeding may not be possible/1uicker 7than the many generations of, selective breeding/backcrossing8 stated disad$antage; detail; e.g. cannot precisely position insert 7so8 unknown/unanticipated effect/may pass to other species 7with unknown/undesirable, effect8/regarded as ethically undesirable 7no market/crop destroyed by protesters8/cannot breed from 9: 7re1uires cloning8

%
[4]

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45.

benefits a$oids in:ections / pain of in:ections / children@s fear of in:ections ; mimics normal pancreatic beha$iour ; more stable homeostasis / reduced highs and lo&s in blood sugar ; less chance( hypoglycaemia / hyperglycaemia ; less restriction on lifestyle ; no need to measure blood sugar ; A)* ; problems re:ection ; cells could lodge else&here ; may take longer to act ; A)* ; e.g. rat data may not be applicable to humans( transgene may ha$e unforeseen effect

max (

max (

ma !
[4]

46.

humans are eukaryotes / )scherichia coli is a prokaryote ; humans / eukaryotes have 7accept ora8 larger( proteins / genes ; introns ; ?:unk@ 6=A / non-coding 6=A ; repeating sequences ; centromeres / telomeres ; fossil genes ; )" coli cell much smaller ; ora selection for( less &aste of space / more compact genome ; % ma
[2]

47.

insulin is( polypeptide / protein ; (promoter)( s&itches on transcription or makes gene produce( m<=A / insulin ; as blood glucose rises insulin production increases ; ref to figures &ith units ; only produced &hen needed ; ref to( homeostasis / negati$e feedback ;

ma '
[3]

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48.

meristematic/pluripotent/totipotent/cambial/undifferentiated( tissue; sterile conditions; nutrient medium to encourage( di$ision/mitosis; produces callus; subdi$ided; different (nutrient) medium to encourage differentiation; detail of either medium; e.g. named nutrient or plant growth substance gro&s to plantlet; hardening medium/sterile soil;

ma 1
[5]

The Henrietta Barnett School

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