Markscheme May 2016 Biology Higher level Paper 3

Transcription

1 M16/4/BIOLO/HP3/ENG/TZ0/XX/M Marksheme May 2016 Biology Higher level Paper 3 23 pages

2 2 M16/4/BIOLO/HP3/ENG/TZ0/XX/M Setion A 1. a a. negative orrelation/inverse relationship Do not aept negative alone.. exponential derease in alifiation as pco 2 /onentration/atmospheri CO 2 rises 1 max. as CO 2 inreases alifiation dereases a. allows atmospheri CO 2 onentration to e ontrolled/varied. ontrol other variales 1 max. losed system so no external proesses affet experiment Alternative 1 a. orals have parts/shells/«exo»skeleton made of alium aronate. alium aronate «shells» dissolve in aid onditions. aid/high CO 2 onditions redues availaility of alium aronate «for forming shells» negatively affets enzymes involved in alifiation Alternative 2 d. CO 2 is «signifiant» greenhouse gas ausing rise in oean temperatures e. higher oean temperatures/aidifiation leads to rejetion of zooxanthellae higher oean temperatures/aidifiation leads to oral leahing

3 3 M16/4/BIOLO/HP3/ENG/TZ0/XX/M 2. a xylem 1 a. it has a stylet emedded in it aphids insert their stylets into phloem. is loser to the surfae/exterior/outside the xylem 1 max. ells smaller than xylem tissue «elow it» d. smaller «ompanion» ells are adjaent to larger «sieve tue» ells a. aphids tap into phloem with their stylets «to use sap as a food soure». plants grown in radioative CO 2 / 14 CO 2 inorporate it into arohydrate. phloem ontents/sap/fluid flows through the stylet d. aphid ody severed/ut from stylet «after stylet inserted into phloem» e. analyze «sap/fluid exuded from stylet» for solutes/arohydrates radioative-laelled aron an e deteted «in the phloem sap» f. stylets at different parts of the plant an show sequene/rate of movement 3. a «all» juvenile shoots root more suessfully/signifiantly/show higher perentage rooting suess Need omparative wording for the mark. 1 a. juvenile shoots have more undifferentiated/meristem/dividing tissues. juvenile shoots have faster response to auxin 1 max

4 4 M16/4/BIOLO/HP3/ENG/TZ0/XX/M A rief desription is required rather than a simple naming of the variale. a. the starting leaf area/size/mass/length of utting would need to e kept similar in all treatment groups. light/temperature/nutrients/rooting mixture/moisture would need to e the same for all plants and oth treatment groups. utting taken from same relative point of the shru/ranh Aept other reasonale answers. 1 max d a. inreases ell elongation/growth/enlargement has effet on rate of mitosis. hanges the pattern of gene expression promotes transription of some genes. hanges the ph of the extraellular environment/ell wall inreases ativity of proton pumps d. reaks ross links/onnetions etween ellulose fires in ell wall e. inreases ell wall plastiity f. «varying» auxin onentrations have different effets in different parts of the plant

5 5 M16/4/BIOLO/HP3/ENG/TZ0/XX/M Setion B Option A Neuroiology and ehaviour 4. a i 8 months 1 ii a. neural pruning loss of neurons. through apoptosis/programmed ell death. loss of dendrites/axon ranhes/synapse elimination d. due to lak of use e. «in older age» damage to rain/strokes/hemial ause I: interneuron/relay neuron II: sensory neuron 2 arrow drawn on diagram to show orret diretion of impulse Arrow an also e a single loop through interneuron showing omplete pathway or two arrows to and from interneuron. 1

6 6 M16/4/BIOLO/HP3/ENG/TZ0/XX/M 5. a the higher the ody mass, the higher the rain mass positive orrelation 1 at 1 a. ratio for humans is furthest aove line of est-fit/orrelation urve. although elephant/whale have muh larger ody mass than human the ratio is smaller than human elephants/dolphins/lue whales have greater rain mass ut muh larger ody mass. himp with similar ody mass has lower rain mass d. average ody mass does not indiate variation within speies e. data not lear as oth sales are exponential mp e: Aept other disussion to explain why data not lear.

7 7 M16/4/BIOLO/HP3/ENG/TZ0/XX/M 6. a. more than one presynapti neuron an form a synapse with the same postsynapti neuron. summation involves omining the effets of «exitatory and inhiitory» neurotransmitters/potentials ation potentials form depending on the alane of signals of exitatory and inhiitory signals. E1 and E2/two exitatory potentials/effets are added d. «E1 and E2/two exitatory potentials» depolarizes memrane e. «memrane potential» goes aove threshold generate ation potential f. effet of inhiitory neurotransmitter/potential/ I1 anels effet of exitatory neurotransmitter/e1 effet of inhiitory neurotransmitter/potential/ I1 prevents threshold eing reahed when E1 applied

8 8 M16/4/BIOLO/HP3/ENG/TZ0/XX/M 7. a Award [] if no referene to Pavlov s investigation. a. unonditioned stimulus triggers a response automatially/innately. sight/smell of food «naturally» triggers salivation in dogs. onditioned stimulus is a previously neutral stimulus «eg: sound of ell» d. that eomes assoiated with the unonditioned stimulus «and is learned» e. triggers a onditioned response, salivation with sound efore food a. food is more aundant. temperature is more tolerale. more suitale haitat Alternative 1 a. females have their us/are latating at same time. an sukle/are for eah other s us while others hunt. us are more likely to survive when they are raised in a nursery rather than y a solitary mother Alternative 2 d. a group of male us, of same age, leave the pride at the same time e. so an ompete for dominane of another pride more effetively

9 9 M16/4/BIOLO/HP3/ENG/TZ0/XX/M d a. involve hanges in neurons aused y slow-ating neurotransmitters. neurons make new onnetions/inrease numer of synapses. «short-term» memory depends on hange in strength of existing neuronal onnetions d. long-term potentiation «LTP» is a lasting inrease in strength of synapti transmission e. more reeptors added to enhane synapti transmission 8. a. deteted y the ones ones are photoreeptors. they are loated in the retina/onentrated in the fovea. three types of ones that asor different wavelengths of «visile» light d. ones asor light passing impulse to ipolar ell e. ipolar ells onneted to ganglion ells 6 max f. there is one to one onnetion of ones to ipolar ells one to one onnetion of ipolar ells to ganglion ells g. relayed to the opti nerve h. right field of vision «of oth eyes» is sent to the left part of the rain Vie versa i. information is passed to the visual ortex/oipital loe

10 10 M16/4/BIOLO/HP3/ENG/TZ0/XX/M Option B Biotehnology and ioinformatis 9. a a. NADH is required as a reduing agent/eletron donor/hydrogen donor/o-enzyme/limiting fator for the prodution of suinate. high levels of FDH1 produe greater quantities of NADH whih is required for onversion of gluose «via intermediates» to suinate 1 max a. latate/ethanol. CO 2 «favoured y high FDH1 levels» a. raw materials are supplied in ontinuous amounts. produts/wastes are ontinuously extrated. onditions are monitored/regulated to keep variales at a steady state 1 max d geneti proesses/rate limiting hemials/regulatory proesses are eing optimized a i resistane is «exponentially» inreasing OWTTE 1 ii a. inreased growth/differential survival of resistant population natural seletion for glyphosate resistane. evolution of resistane is possile due to pre-existing variaility. «strong» seletive pressure «y appliation of glyphosate» 1 max

11 11 M16/4/BIOLO/HP3/ENG/TZ0/XX/M a. inreased rop yields redued demand for more land. less appliation of other heriides «to ontrol weeds» glyphosate an replae more toxi/persistent heriides. less need for tilling/plowing/ploughing less soil erosion d. «less plowing/heriide appliation» uses less fuel/less emissions produed a. Agroaterium tumefaiens «Ti» plasmid auses tumours in the plant it infets. donor gene inserted into Ti plasmid. along with antiioti resistane gene d. onstrut/reominant Ti plasmid re-inserted into an A. tumefaiens aterium e. infet leaf with aterium «and grow on antiioti medium» f. «some surviving» ells ontain the gene/are glyphosate resistant

12 12 M16/4/BIOLO/HP3/ENG/TZ0/XX/M 11. a uses it as an energy soure/aron soure/eletron aeptor Do not aept metaolizes it. 1 a. to allow for the formation of a iofilm does not get washed away/an e re-used. inreases surfae area whih inreases ontat etween ateria and dye 1 max a. name of miroorganism eg: Pseudomonas Must use at least Genus name.. name of pollutant eg: oil. outline of ation eg: uses oil as energy/aron soure degrades oil Allow other valid heked examples a it is from a North Atlanti population 1 it is from dolphin/speies that is not on the list 1 a. olleted DNA sample is small/too minute to study. DNA from tissue sample amplified «y PCR» otain inreased yields/quantities of speifi DNA sequenes. test primers «from legal speies» are used d. example of genes used «to onstrut test primers» eg: 18S riosome, ytohrome C oxidase e. if no amplifiation ours, then test is negative

13 13 M16/4/BIOLO/HP3/ENG/TZ0/XX/M d a. sequene a sample of DNA/protein from the tissue. run a BLAST/sequenes alignment software searh for similar sequenes «of DNA/protein». a math an e used for speies identifiation perentage similarity of sequenes used to uild up ladogram d. BLASTp is used if protein sequened AND BLASTn if DNA sequened Both needed. 13. a. infeted individual will have pathogens/antigens in odily fluids. test ontains immoilized/fixed antiodies to the pathogen/antigen. if present, antigen inds to «immoilized» antiody/apture moleule d. solution is washed and only fixed antigen-antiody omplexes persist e. then a detetion antiody linked to an enzyme is added f. reats with fixed antigen-antiody omplex 6 max g. a hromogeni/potentially fluoresent sustane is added h. enzyme hanges sustane to a different/detetale olour i. the presene of olour is a positive response/asene of olour a negative response

14 14 M16/4/BIOLO/HP3/ENG/TZ0/XX/M Option C Eology and onservation 14. a a. line transet a line is identified and individual walks the line. deision on where to start and end the line/transet. samples taken every 20 m/at regular intervals a. ativity of soil miroorganisms/ammonifiation/nitrogen fixation. urine/fees/other nitrogenous waste. dead organisms d. fertilizers «on edge of forest» a. greater distane from an open field where they are applying fertilizer. more ammonium asored/reyled 1 max. less ammonium in rain reahes soil/trapped in treetops

15 15 M16/4/BIOLO/HP3/ENG/TZ0/XX/M 15. a a. P. gonoephala is found over a greater range of temperatures Note: do not aept just numers (T) of ranges without omparing/ontrasting learly.. P. gonoephala is found etween 16.5 degrees and 23.0 degrees whereas P. montenegrina is not P. gonoephala is found at a higher temperature. oth are found in temperatures of 6.5 degrees to 16.5 degrees Do not aept oth show a greater range alone as this omes from graph C not A and B as the question asks. a. realized nihe is that whih organism atually oupies. presene of another speies/p. gonoephala narrows the nihe. limited y ompetition ompetitive exlusion d. the realized nihe is older/smaller range in the presene of P. gonoephala

16 16 M16/4/BIOLO/HP3/ENG/TZ0/XX/M 16. a a. inreases. at a greater rate early on. seems to plateau/levels off a. forest developed. inrease in iomass «over years» requires rainfall. water is a limiting fator to photosynthesis a. initially there is low ompetition for sunlight/resoures. photosynthesis allows aumulation of iomass. iomass rises as larger plants replae smaller plants d. «in later stages» iomass inrease limited due to ompetition for resoures iomass stailizes as limax ommunity reahed d a. development of mature trees requires xylem/wood. xylem/wood ontriutes to iomass ut not respiration. photosynthesis/prodution greater than respiration d. photosynthesis/prodution ontinues to aumulate iomass aumulated iomass remains/inreases

17 17 M16/4/BIOLO/HP3/ENG/TZ0/XX/M 17. a «oloured ojet» mistaken for food skimming of oean surfae for food leads to plasti intake 1 a. oean urrents onentrate plasti deris. Kure reeives more deris than Oahu. more plasti availale/more exposure to human populations/waste in the environment of Kure a. «maro» plastis lown/arried/washed from land soures into the oean. degraded overtime. to form miroplasti fragments d. sustanes already ontaining miroplastis «eg: washing/leansing produts» get into water d a. miroplasti ingested y organisms at lower trophi levels. aumulates in the tissues/guts of organisms. eomes onentrated in the organs/tissues of organisms as moves through the food hain/at higher trophi levels

18 18 M16/4/BIOLO/HP3/ENG/TZ0/XX/M 18. a. sampling does not ount every organism so may not e a true estimate. highly moile marine animals unevenly distriuted so diffiult to estimate population size. transets/quadrats used to estimate populations of stationary organisms d. useful on roky shores/eahes/intertidal zones/reef e. estimation of moile larval stages of stationary organisms/oral more diffiult f. apture-mark-release-reapture useful for moile animals in restrited environments Vie versa g. example of organism an estimate y this tehnique 6 max h. drawak of tehnique i. eholoation/sonar used to estimate the population size of fish that form shoals j. eholoation annot distinguish etween speies Aept other valid limitation. k. the age struture of «ommerially» aught fish an e used to estimate population size l. restrited-age fish «as yath» dumped efore landing so iased estimates depends on auray/honesty of those athing fish

19 19 M16/4/BIOLO/HP3/ENG/TZ0/XX/M Option D Human physiology 19. a a. «essential amino aids» must e otained from the diet. they annot e synthesized y the ody they annot e synthesized from other amino aids i tyrosine an only e synthesized when phenylalanine is in the diet Aept inverse: if phenylalanine is not in the diet the person will not e ale to synthesize tyrosine. 1 ii reessive inherited «geneti» ondition they lak «the enzyme» phenylalanine hydroxylase mutated form of PAH gene 1 a. ontain all of the essential amino aids. human milk has higher levels of 5 «out of 9» essential amino aids than ow milk human milk has the same or more of essential amino aids exept histidine and lysine ompared to ow milk. human milk is the same or higher in all essential amino aids exept histidine ompared with hen egg human milk has higher levels of 4 «out of 9» essential amino aids ompared with hen egg d. «limitation» human milk ontains less histidine than oth hen egg AND ow milk Both needed.

20 20 M16/4/BIOLO/HP3/ENG/TZ0/XX/M d Award [] if response only mentions one of the hormones. Prolatin a. produed y the anterior pituitary. stimulates mammary glands to grow. stimulates the prodution of milk Oxytoin d. produed in neuroseretory ells «in hypothalamus» stored/sereted y posterior pituitary e. sukling/nursing stimulates oxytoin release example of positive feedak f. «ontrations» ause ejetion/release of milk from mammary glands e a. presene of duts. presene aini/ainar/seretory ells. duts leads to a ody surfae/avity/gut

21 21 M16/4/BIOLO/HP3/ENG/TZ0/XX/M 20. a 38 hours Aept 38 hours to 40 hours. Units required. 1 a. higher digestile matter ontent, longer residene time. slower movement/peristalsis due to lak of fier. fier/indigestile material attrats water to fees/lumen/intestinal ontents d. more digestile material inreases water asorption «into large intestine» e. hardens stool/onstipation and further inreases residene time 21. a a. septum depolarizes signal from AVN/atrioventriular node. onduting fiers arry impulses through the ventrile wall arry impulse through Bundle of His/Purkinje fiers. ventriles depolarize atrioventriular valves lose d. atria repolarize e. ventrile ontration/systole initiated Do not aept the alternative mp if other valves losing is mentioned as well.

22 22 M16/4/BIOLO/HP3/ENG/TZ0/XX/M a. epinephrine/peptide/protein/hydrophili hormones ind to «reeptors in» plasma memrane. involves synthesis/release/ativation of seond messenger/yli AMP/AMP. triggers asade of events d. leads to promotion/inhiition of enzymes auses ativation of protein kinase e. auses the hormone effet use a defirillator to restore/reset normal rhythm/to shok the heart/restore heart eat appliation of an eletri disharge to the hest to restore normal rhythm Do not aept paemaker Need something more than one word answer as this is an outline. 1 d a. high CO 2 levels lead to derease in ph/inreased aidity Aept inverse statements using low CO 2 onentration/higher ph.. hemoreeptors found in the medulla olongata/aorta/arotid artery. they are ale to detet a hange in lood ph/co 2 onentration d. «hemoreeptors» send message/impulse to the respiratory entre e. respiratory entre «in medulla olongata» ontrols ventilation rate f. triggers an inrease in the ventilation rate to rid the ody of CO 2

23 23 M16/4/BIOLO/HP3/ENG/TZ0/XX/M 22. a. stores gluose as glyogen releases gluose from glyogen. under influene of insulin/gluagon «respetively» depending on lood gluose levels. some nutrients in exess an e stored in the liver Aept vitamin A or D stored. d. the liver detoxifies lood the liver removes/reaks down toxins/alohol/drugs «from the lood» e. Kupffer ells engulf ateria f. Kupffer ells reakdown erythroytes/red lood ells/hemogloin y phagoytosis 6 max g. hemogloin is split into heme and gloin h. iron from heme/hemogloin reakdown is arried to the one marrow «to produe new hemogloin in new red lood ells» exess iron stored in liver i. surplus holesterol is onverted to ile salts holesterol is synthesized j. «hepatoytes» produe plasma proteins Aept speifi plasma proteins suh as alumin.