Biology Higher level Paper 3 - 2K18 Y'ALL CAN'T HANDLE...

transcript

44EP01

42 pages

M16/4/BIOLO/HP3/ENG/TZ0/XX

BiologyHigher levelPaper 3

Instructions to candidates

• Write your session number in the boxes above.• Do not open this examination paper until instructed to do so.• Section A: answer all questions.• Section B: answer all of the questions from one of the options.• Write your answers in the boxes provided.• A calculator is required for this paper.• The maximum mark for this examination paper is [45 marks].

Option Questions

Option A — Neurobiology and behaviour 4 – 8

Option B — Biotechnology and bioinformatics 9 – 13

Option C — Ecology and conservation 14 – 18

Option D — Human physiology 19 – 22

1 hour 15 minutes

Thursday 5 May 2016 (morning)

2216 – 6003

Candidate session number

44EP02

– 2 – M16/4/BIOLO/HP3/ENG/TZ0/XX

Section A

Answer all questions. Write your answers in the boxes provided.

1. Increasingcarbondioxideconcentrationintheatmosphereleadstoacidificationoftheocean.Thisinturnreducestheamountofdissolvedcalciumcarbonate.Astudywasundertakentoinvestigatetheeffectofincreasingtheconcentrationofatmosphericcarbondioxideonthecalcificationrateofmarineorganisms.Calcificationistheuptakeofcalciumintothebodiesandshellsofmarineorganisms.ThestudywasundertakeninsideBiosphere-2,alarge-scaleclosedmesocosm.Thegraphshowstheresultsofthedatacollection.

[Source:©InternationalBaccalaureateOrganization2016]

(a) Statetherelationshipbetweenatmosphericcarbondioxideandcalcificationrates. [1]

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(b) Suggest oneadvantageofusingamesocosminthisexperiment. [1]

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(This question continues on the following page)

00 200 400 600 800

Calci�cation / mmol CaCO3m-2day-1

pCO2 / µatm

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(Question 1 continued)

(c) Outlineonewayinwhichreef-buildingcoralsareaffectedbyincreasingatmospheric carbon dioxide. [2]

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44EP04

2. The image shows a severed aphid stylet embedded in plant tissue.

(a) IdentifythetissuelabelledII. [1]

II. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Stylet

(b) OutlineonepieceofevidencethatthetissuelabelledIisphloemtissue. [1]

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(c) Explainhowaphidstyletscanbeusedtostudythemovementofsolutesin plant tissues. [3]

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44EP06

–6– M16/4/BIOLO/HP3/ENG/TZ0/XX

3. Achievingsuccessfulrootingofcuttingsisdifficultinsomeshrubspecies.Anexperimentwasundertakentodeterminewhetherjuvenileshoots(J)ofshrubsrootmoresuccessfullythan mature shoots (M).

Rooting success / %

1009080706050403020100

Arbutusunedo

Laurusnobilis

Myrtuscommunis

Oleaeuropaea

Phillyrealatifolia

Pistacialentiscus

Viburnumtinus

M J M J M J M J M J M J M J

Key: mature shoots (M) juvenileshoots(J)

[Source:“EffectsofrejuvenationoncuttingpropagationofMediterraneanshrubspecies”byG.PignattiandS.Crobeddu,Forest@,vol.2,pp.290-295(Sep2005):Figure3.Usedwithpermission.]

(a) Distinguishbetweentherootingsuccessofthejuvenileshootsandthematureshoots. [1]

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(b) Suggest onereasonforthedifferenceintherootingsuccessinthejuvenileshootsandthe mature shoots. [1]

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(c) Outlineone variable that would need to be controlled in this experiment. [1]

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(d) Auxinisahormonethatcanbeappliedtoimprovethepercentagesuccessofrootinginthosestudyplantswithpoorrootingsuccess.Explaintheeffectsofauxinonplant cells. [3]

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44EP08

Section B

Answer all ofthequestionsfromoneoftheoptions. Write your answers in the boxes provided.

Option A — Neurobiology and behaviour

4. Synapticdensityisthenumberofsynapsesperunitvolume.Thegraphshowsthesynapticdensityfora28-week-oldfetus,andfrombirthtoage70.

Synaptic density ×108 mm–3

028-week Birth 2 4 6 81012 2 5 10 20 30 50 70

fetus Months Years

(a) (i) Determine the age when synaptic density is highest. [1]

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(ii) Explainhowsynapticdensitydecreasesaftertheagedeterminedin(a)(i). [3]

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(Option A continues on the following page)

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(Option A, question 4 continued)

(b) Labelthediagramofthereflexarcwiththenamesoftheneuronsindicated. [2]

I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

II. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Receptors intheskin

Effector (muscle)

[Source:adaptedfromhttp://image.tutorvista.com]

(c) Drawanarrowonthediagramofthereflexarctoshowthedirectionofimpulses. [1]

44EP10

(Option A continued)

5. Thescattergraphshowstherelationshipbetweenbrainmassandbodymassforanumberofanimals.Somerepresentativeanimalsareindicatedwhilethedottedlinerepresentstherangeofvaluesseenforamuchlargergroupofanimals.

(a) State the relationship between body mass and brain mass. [1]

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(b) Identifytheanimalwiththelowestbrainmass. [1]

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GraphremovedforcopyrightreasonsPleasegoto:http://cr2chicago.weebly.com/with-every-drop/behavior-and-social-interaction-in-a-wet-world-part-ii-whale-

vocalizations-and-communication

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(c) Discusstheevidenceprovidedbythescattergraphforthehypothesisthathumanshave the largest relative brain mass to body mass ratio. [3]

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44EP12

6. Thegraphscomparethechangesinmembranepotentialthatresultfromacombinationofstimuli.GraphAshowstwoexcitatorypost-synapticpotentials(E1 and E2) acting on aneuron.GraphBshowsoneexcitatory(E1) and one inhibitory (I1)post-synapticpotential,both acting on a neuron.

Withrespecttothegraphs,explainwhatismeantbysummation. [3]

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Membrane potential/ mV

Graph A Graph B

E1+E2E1+I1I1

Time Time

-55-70

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7. (a) WithrespecttoPavlov’sexperimentswithdogs,distinguishbetweentheconditionedand unconditioned stimulus. [3]

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(b) Thebirdknownastheblackcap(Sylvia atricapilla)traditionallymigratesfromitssummerbreedinggroundsinCentralEuropetoSpainandPortugalforthewinter.State twoadaptiveadvantagesofbirdmigration. [2]

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(c) Outlineonewayinwhichsynchronizedoestrusinfemalelionsincreasesthechancesofsurvivalandreproductionofoffspring. [2]

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44EP14

(d) Outlineone way in which neurons can be altered by memory and learning. [2]

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8. Explain how colour in the environment is detected by the eyes and relayed to the brain in humans. [6]

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End of Option A

44EP16

Option B — Biotechnology and bioinformatics

9. Succinateisindustriallyproducedbycontinuousfermentation.Itisusedasarawmaterialintheproductionofflavourenhancers,drugsandindustrialchemicals.OnemethodofincreasingtheproductionofsuccinateistogeneticallymodifyE. coli to express high levels offormatedehydrogenase(FDH1).ThisresultsintheproductionofhigherconcentrationsofNADH.Theengineeredpathwayisshownasabolddottedlineintheimage.

Pyruvate

Acetyl-CoA

Ethanol

Acetate

Glucose

Succinate

Formate

Lactate NADH NAD+

[Source:Ka-YiuSan,E.D.ButcherProfessorofBioengineering,ProfessorofChemicalEngineering,RiceUniversity.]

(a) Usingthediagram,suggestareasonforhighconcentrationsofNADHfavouringtheproductionofsuccinate. [1]

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(Option B continues on the following page)

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(Option B, question 9 continued)

(b) PredictonemetaboliteotherthansuccinatethatwillbeproducedingreateramountsiftheamountofNADHavailableisincreased. [1]

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(c) Outlinetheprocessofcontinuousculturefermentation. [2]

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(d) Outlineonereasonthisprocess,toincreasetheproductionofsuccinate,representspathway engineering.

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44EP18

(Option B continued)

10. Annual ryegrass (Lolium rigidum)isaweedspeciesthathasbeensuccessfullycontrolledbytheapplicationoftheherbicideglyphosate.ThegraphshowsthenumberofconfirmedcasesofglyphosateresistantryegrassacrossAustraliabetween1996−2012.

Numberofresistant

populations

0 1996 2000 2004 2008 2012

[Source:adaptedfromwww.grdc.com.au]

(a) (i) Outlinethepatternofchangeinresistantpopulationsofryegrassovertimein Australia. [1]

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(ii) Suggest onereasonforthepattern. [1]

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(b) State twoenvironmentalbenefitsfromtheuseofgeneticallymodifiedglyphosateresistant soybeans. [2]

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(c) ExplaintheroleoftheAgrobacterium tumefaciensTiplasmidingeneticmodification. [3]

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(Option B continues on page 21)

44EP20

Pleasedo not write on this page.

Answers written on this pagewillnotbemarked.

44EP21

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(Option B continued from page 19)

11. ThedyeReactiveBlack5(RB5)iswidelyusedfordyeingintextileindustries.Removalofthedyefromfactorywaste-waterisimportantnotonlyforaestheticreasonsbutalsobecausethe dye can lead to mutations that may lead to cancer. Paenibacillus is a bacterium that can metabolizethedye.

(a) Suggest one way in which organisms such as Paenibacillus metabolizetoxic substances. [1]

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(b) ThedecontaminationsystemfortheremovalofthedyeusesasurfacetowhichPaenibacillus can attach. Suggest oneadvantageofprovidingasurfaceforattachment. [1]

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(c) Outlineanothernamedexampleofamicroorganismusedinbioremediation. [3]

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44EP22

12. Internationalagreementlimitsthehuntingofwhales.OnlythemeatoftheMinke,FinandHumpbackwhalesfromSouthernHemispherepopulationsisallowedtobesoldonthedomesticmarketinJapan.Scientistsobtainedfivesamplesoffoodthatwerebeingsoldas“whalemeat”inaJapanesemarketplace.Theyidentifiedthespeciesandprobablegeographicoriginofthemeatusinggeneticanalysis.Theresultswereusedtoconstructthe cladogram.

Minkewhale(Antarctic)Minkewhale(Australia)

Minkewhale(northAtlantic)sample 1

Humpbackwhale(northAtlantic)Humpbackwhale(northPacific)sample 2

sample 3Finwhale(Mediterranean)Finwhale(Iceland)

sample 4sample 5Hector’sdolphinCommerson’sdolphin

[Source:AdaptedfromC.S.BakerandS.R.Palumbi(1994),Science,256(5178),pages1538–1539.(http://www.soest.hawaii.edu/oceanography/courses_html/OCN331/Baker%26Palumbi.pdf).ReprintedwithpermissionfromAAAS.Readersmayview,browse,and/ordownloadmaterialfortemporarycopyingpurposesonly,providedtheseusesarefornoncommercialpersonalorclassroompurposes.Exceptasprovidedbylaw,thismaterialmaynotbefurtherreproduced,distributed,transmitted,modified,

adapted,performed,displayed,published,orsoldinwholeorinpart,withoutpriorwrittenpermissionfromthepublisher.]

(a) Usingthedatainthecladogram,statethereasonforsaleofSample1meatbeingillegalinJapan. [1]

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(b) Usingthedatainthecladogram,statethereasonforsaleofSample4meatbeingillegalinJapan. [1]

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(c) Outlinehowthepolymerasechainreaction(PCR)mighthavebeenusedinthisstudy. [3]

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(d) Explainhowsequencealignmentsoftwaremighthavebeenusedinthisstudy. [2]

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44EP24

13. ExplainhowinfectionbyapathogencanbedetectedbyanELISAtestforantigens. [6]

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End of Option B

44EP25

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Pleasedo not write on this page.

Answers written on this pagewillnotbemarked.

44EP26

Option C — Ecology and conservation

14. Wherehighamountsofammoniumionsarepresentinagriculturalareas,gaseousammoniacan be released into the atmosphere. This ammonia can dissolve and be carried across distancesandthenbedepositedthroughprecipitation.Inastudyoftheeffectsofdepositionofammoniuminaforest,soilsamplesweretakenstartingattheforestedgenexttoan openfieldandmovingtowardthecentreoftheforest.

Soil ammonia / mgkg–1 oven dry soil

00 20 40 60 80 100 120 140 160 180 200 Distancefromforestedge/m

[Source:“Spatialvariationsofnitrogendepositionanditseffectonforestbiochemicalprocesses”,M.A.Suttonet al. CrownCopyright,courtesyForestryCommission,licensedundertheOpenGovernmentLicence.

http://www.forestry.gov.uk/fr/INFD-75PJ9E#sutton2001(accessedMay2016).]

(a) Outlinetheprocedurethatwasmostlikelyusedbytheresearcherstodecidewheretotakethesamples. [2]

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(Option C continues on the following page)

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(Option C, question 14 continued)

(b) List twosourcesoftheammoniumintheforestsoilsapartfromdepositioninrainfall. [2]

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(c) Suggest onereasonforammoniumlevelsintheinterioroftheforestbeinglowerthanthe soil ammonium close to the edge. [1]

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44EP28

(Option C continued)

15. Thefigureshowsthedistributionoftwospeciesoffreshwaterflatworms,Planaria gonocephala and Planaria montenegrina,overarangeofstreamtemperatures.GraphAandgraphBshowthedistributionswheneachspeciesisseparatefromtheother.GraphCshowsthedistributionwhentheyarefoundlivingtogether.

GraphA P. montenegrina

6.5 16.5 23.0Temperature / °C

GraphB P. gonocephala

6.5 16.5 23.0Temperature / °C

GraphC P. montenegrina

P. gonocephala

5 10 15 20 25 Temperature / °C

[Source:R.J.Putman(1994)Community Ecology,page63.©KluwerAcademicPublishersBoston.Usedwithpermission.]

(a) UsinggraphAandgraphB,compareandcontrastthetemperaturerangesofthetwospecieswhentheyarefoundseparately. [2]

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(b) Explain,withrespecttotheexampleofP. montenegrina,whatismeantbyrealizedniche. [2]

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44EP30

16. Thegraphisamodelshowingbiomassandrespirationlevelsinafieldwherefarmingstopsattimezeroandtheabandonedlanddevelopsintoforest.

Forestsuccession

Biomass

Respiration

0 20 40 60 80 100Years

[Source:From“TheStrategyofEcosystemDevelopment”byEugeneP.Odum.Science,18Apr1969:Vol.164,Issue3877,pp.262-270.ReprintedwithpermissionfromAAAS.]

(a) Describethechangeinbiomassoverthe100yearperiod. [2]

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(b) Outlinetheevidencefromthegraphthattheareahadplentifulrainfall. [2]

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(c) Explain the changes in biomass. [2]

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(d) Explainwhybiomasscontinuestoincreaseaftertherespirationlevelsplateau. [2]

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44EP32

17. The Laysan Albatross (Phoebastria immutabilis) sometimes ingests plastic. A bolus is apelletmadeofmaterialthatthealbatrosscannotdigest,sobringsitbackupfromitsstomachtoitsmouthandthenejectstheindigestiblematter.GraphAindicatesthemassofindigestiblenaturalmaterial,suchasbonesandoctopusbeaks,inthebolusofbirdsattwodifferentlocations.GraphBindicatesthemassofplasticinthebolusatbothlocations.

GraphA

1009080706050403020100

Oahu Kure Locations

GraphB

1009080706050403020100

Oahu Kure Locations

[Source:YoungLC,VanderlipC,DuffyDC,AfanasyevV,ShafferSA(2009)BringingHometheTrash:DoColony-BasedDifferencesinForagingDistributionLeadtoIncreasedPlasticIngestioninLaysanAlbatrosses?

PLoS ONE4(10):e7623.doi:10.1371/journal.pone.0007623]

(a) Suggest onereasonfortheLaysanAlbatrossingestingindigestibleplastic. [1]

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(b) SuggestareasonforthedifferenceiningestedplasticinthedietsoftheLaysan Albatross in the two locations. [2]

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44EP33

– 33 –

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(c) Outlinetheoriginofmicroplasticdebrisinthemarineenvironment. [2]

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(d) Usingmicroplasticsasanexample,outlinetheconceptofbiomagnification. [2]

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44EP34

18. Evaluatethemethodsusedtoestimatepopulationsofmarineorganisms. [6]

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End of Option C

44EP35

– 35 –

Turn over

Option D — Human physiology

19. Thetablesummarizestherelativecontentofessentialaminoacidsindifferentfoods.Cysteineandtyrosineareclassifiedasbeing“conditionallyessential”.Thequantityofeachaminoacidinaheneggissetas1.0andallothervaluesarerelativetotheheneggstandard.

Hen egg Human milk Cow milk

Isoleucine 1.0 1.1 1.1

Leucine 1.0 1.4 1.3

Valine 1.0 1.0 1.0

Threonine 1.0 1.0 0.9

Methionine and Cysteine 1.0 1.1 0.7

Tryptophan 1.0 1.6 1.3

Lysine 1.0 1.0 1.3

Phenylalanine and Tyrosine 1.0 1.0 0.9

Histidine 1.0 0.9 1.1

[Source:DataobtainedfromRobertMcGilvery,Biochemistry: A Functional Approach,1970,W.B.Saunders.]

(a) Outlinewhatismeantbythetermessentialaminoacid. [2]

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(Option D continues on the following page)

44EP36

(Option D, question 19 continued)

(b) Phenylalanineisconvertedtotyrosinebytheenzymephenylalaninehydroxylase.

Phenylalaninehydroxylase

Phenylalanine Tyrosine

(i) Deduce the reason that tyrosine is considered to be a conditionally essential amino acid. [1]

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(ii) Wheninfantswiththeconditionphenylketonuria(PKU)areleftuntreated,theyhaveabuild-upofphenylalanineinthebloodandhighlevelsofphenylalanineintheurine.Statethecauseofthiscondition. [1]

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(c) Evaluatehumanmilkasanoverallsourceofessentialaminoacids. [2]

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44EP37

– 37 –

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(d) Outlinethecontrolofmilksecretionbyoxytocinandprolactin. [3]

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(e) Thediagramrepresentsalobulefromamammarygland.Themammaryglandisanexampleofanexocrinegland.

[Source:LuisABate,ProfessorofPhysiologyandEthology,UniversityofPrinceEdwardIsland.Usedwithpermission.]

Identifytwofeaturesofanexocrineglandvisibleinthediagram. [2]

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44EP38

(Option D continued)

20. Thegraphshowsthelengthoftimethatthecontentofamealtakestopassthroughthegutasafunctionofdigestiblemattercontent.Themoredigestiblematterpresentinthemeal,thelowerthedietaryfibrecontent.

Mean residence time / h

00 20 40 60 80

Digestible matter / %ofmassofmeal

(a) Estimatethemeanresidencetimeofamealwith50%digestiblematter. [1]

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44EP39

– 39 –

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(b) Explaintherelationshipbetweenpercentageofdigestiblematterandmeanresidencetime. [3]

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44EP40

21. ThediagramshowsanECGtracewiththeQRScomplexindicated.

QRScomplex

(a) OutlinetheeventsofthecardiaccyclethatareoccurringduringthisQRSinterval. [2]

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(b) Heartrateisaffectedbythehormoneepinephrine.Theactionofepinephrineismediatedbyachemicalcalledasecondmessenger.Explainthemechanismofactionofasecondmessenger. [3]

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44EP41

– 41 –

Turn over

(c) Duringcardiacarrest,theventriclesoftheheartmightbegintocontractinanuncoordinatedfashion.Outlinethetreatmentusedforthiscondition. [1]

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(d) Explaintheroleofchemoreceptorsintheregulationofventilationrate. [3]

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44EP42

22. Outlinethewaysinwhichtheliverregulatesthechemicalandcellularcompositionof the blood. [6]

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End of Option D

44EP43

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Answers written on this pagewill not be marked.

44EP44

Please do not write on this page.

Answers written on this pagewill not be marked.

Biology Higher level Paper 3 - 2K18 Y'ALL CAN'T HANDLE...

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