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AQA A LEVEL BIOLOGY REVISION EXAM QUESTIONS AND ANSWERS LATEST UPDATE., Exercises of Advanced Education

Howard UniversityAdvanced Education

AQA A LEVEL BIOLOGY REVISION EXAM QUESTIONS AND ANSWERS LATEST UPDATE.AQA A LEVEL BIOLOGY REVISION EXAM QUESTIONS AND ANSWERS LATEST UPDATE.AQA A LEVEL BIOLOGY REVISION EXAM QUESTIONS AND ANSWERS LATEST UPDATE.AQA A LEVEL BIOLOGY REVISION EXAM QUESTIONS AND ANSWERS LATEST UPDATE.

Typology: Exercises

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AQA A LEVEL BIOLOGY REVISION EXAM
QUESTIONS AND ANSWERS LATEST
1. Describe how you would use a biochemical test to show that a solution
contained a non-reducing sugar, such as sucrose. [3]: ,first reducing sugars test;
boil with dilute HCl acid then Neutralise with NaHCÑ, add benedict and heat to 95
degrees C brick red ppt forms if reducing sugar is present
2. Describe a chemical test you could carry out to show that a piece of coconut
contains lipids. [3]: (Crush in) ethanol / alcohol; Add (to) water (Order of adding is
critical for this point); Emulsion / white colour
3. Explain what is meant by a polymer. [1]: Molecule) made up of many identi-
cal/similar molecules/monomers/ subunits;
4. Name the reaction which occurs when starch is broken down into maltose.
[1]: Hydrolysis
5. What is the formula for lactose? [2]: C12 ; H22L1
6. Describe how ²-glucose molecule differs from a molecule of -±glucose. [1]: H
at top right end (instead of OH) / OH at bottom (carbon 1)
7. Show two ways in which the structure of cellulose is different from the
structure of starch. [2]: Starch 1,4 and 1,6 bonds / branching Cellulose 1,4 bonds
/ no 1,6 bonds / straight; starch All glucoses /monomers same way up cellulose
Alternate glucoses upside down; starch Helix / coiled/compact cellulose Straight;
Starch monomer Alpha glucose Cellulose monomer Beta glucose
8. Describe the structure of starch and explain how its structure is related to
its function. [3]: Formed from ±glucose; Joined by condensation/ by the removal of a
water molecule/ glycosidic bonds; Between (carbons) 1 and 4 (and 1 and 6); Coiled
chain; compact; (Allows) storage of large amount in a small space; Insoluble so has
no effect on osmosis/water potential; Branches; (Allows) rapid breakdown/release
of glucose / hydrolysis;
9. The structure of a phospholipid molecule is different from that of a triglyc-
eride. Describe how. [2]: triglyceride has three fatty acids and phospholipid has
two; no phosphate group present in triglyceride but present in phospholipid.
10. What is an unsaturated fatty acid? [1]: Some / two carbons with only one
hydrogen / (double bonds) between carbon atoms / not saturated with hydrogen;
11. Describe the structure of cellulose and explain how its structure is related
to its function. [3]: Alternate ²g- lucose rotated 180o, long straight chains, Many
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AQA A LEVEL BIOLOGY REVISION EXAM

QUESTIONS AND ANSWERS LATEST

  1. Describe how you would use a biochemical test to show that a solution contained a non-reducing sugar, such as sucrose. [3]: ,first reducing sugars test; boil with dilute HCl acid then Neutralise with NaHCÑ, add benedict and heat to 95 degrees C brick red ppt forms if reducing sugar is present
    1. Describe a chemical test you could carry out to show that a piece of coconut contains lipids. [3]: (Crush in) ethanol / alcohol; Add (to) water (Order of adding is critical for this point); Emulsion / white colour
    2. Explain what is meant by a polymer. [1]: Molecule) made up of many identi- cal/similar molecules/monomers/ subunits;
    3. Name the reaction which occurs when starch is broken down into maltose. [1]: Hydrolysis
    4. What is the formula for lactose? [2]: C12 ; H22L
    5. Describe how ² - glucose molecule differs from a molecule of - ± glucose. [1]: H at top right end (instead of OH) / OH at bottom (carbon 1)
    6. Show two ways in which the structure of cellulose is different from the structure of starch. [2]: Starch 1,4 and 1,6 bonds / branching Cellulose 1,4 bonds / no 1,6 bonds / straight; starch All glucoses /monomers same way up cellulose Alternate glucoses upside down; starch Helix / coiled/compact cellulose Straight; Starch monomer Alpha glucose Cellulose monomer Beta glucose
    7. Describe the structure of starch and explain how its structure is related to its function. [3]: Formed from ±glucose; Joined by condensation/ by the removal of a water molecule/ glycosidic bonds; Between (carbons) 1 and 4 (and 1 and 6); Coiled chain; compact; (Allows) storage of large amount in a small space; Insoluble so has no effect on osmosis/water potential; Branches; (Allows) rapid breakdown/release of glucose / hydrolysis;
    8. The structure of a phospholipid molecule is different from that of a triglyc- eride. Describe how. [2]: triglyceride has three fatty acids and phospholipid has two; no phosphate group present in triglyceride but present in phospholipid.
    9. What is an unsaturated fatty acid? [1]: Some / two carbons with only one hydrogen / (double bonds) between carbon atoms / not saturated with hydrogen;
    10. Describe the structure of cellulose and explain how its structure is related to its function. [3]: Alternate ²g- lucose rotated 180o, long straight chains, Many

2 / 21 hydrogen bonds join (polysaccharide) chains/molecules to each other / makes microfibrils / gives tensile strength;

  1. Which elements are found in proteins? [1]: Carbon, hydrogen, oxygen, nitro- gen (sometimes sulphur)
  2. Describe how you would use a biochemical test to show that a solution contained protein. [2]: Biuret / alkali + copper sulphate; Lilac/purple/mauve/violet;

4 / 21

  1. A protein molecule contains 150 amino acids. What is the total number of peptide bonds in this molecule? [1]: 149
  2. How do you calculate magnification? [1]: M= I (Image)/ A (actual size)
  3. Describe the ways in which prokaryotic cells and eukaryotic cells differ. [3]: Prokaryotic cells do not have a nucleus / have genetic material in cytoplasm; DNA in loop / ring; Not associated with proteins / do not have chromosomes /chromatin / do not divide by mitosis; Smaller ribosomes; No membrane-bound organelles; Such as mitochondria / lysosomes / endoplasmic reticulum / Golgi / chloroplasts; Prokaryotic cells may have mesosomes; Prokaryotic cells smaller; May be enclosed by capsule;
  4. What is the function of: a)Ribosome b)Smooth ER c)Golgi apparatus d) Chloroplast e)Mitochondria [5]: a)Protein synthesis b)Lipid synthesis and trans- port c)Processing and packaging proteins for secretion d)Photosynthesis e)Aerobic respiration to produce ATP
  5. Explain the advantages and limitations of using a transmission electron microscope [5]: Advantages: Small objects can be seen; TEM has high resolution as wavelength of electrons shorter; Limitations: Cannot look at living cells as cells must be in a vacuum; must cut section / thin specimen; Preparation may create artefact; Does not produce 3D or colored image;
  6. Why an electron microscope can be used to produce images [2]: EM gives high resolution due to short wavelength of electrons;
  7. Explain how viruses cause damage to cells. [3]: uses / breaks up / digests host nuclear / genetic material (allow references made to DNA /RNA instead of nu- clear /genetic); virus DNA / genetic material inserted into hosts DNA / chromosome / genetic material; host cells amino acids are used to synthesize viral proteins; cell lysis; by enzyme (produced by expressing a virus gene); toxin production;
  8. Describe and explain how cell fractionation and ultracentrifugation can be used to isolate mitochondria from a suspension of animal cells. [5]: Cell homogenisation to break open cells; 1. Accept suitable method of breaking open cells. Filter to remove (large) debris / whole cells; 2. Reject removes cell walls. Use isotonic solution to prevent damage to mitochondria / organelles; Keep cold to prevent / reduce damage by enzymes / use buffer to prevent protein / enzyme denaturation; Centrifuge (at lower speed / 1000 g) to separate nuclei / cell fragments / heavy organelles; Re-spin (supernatant / after nuclei / pellet removed) at higher speed to get mitochondria in pellet / at bottom.
  9. Name two structures present in eukaryotic cells that are not present in the cells of prokaryotes. [2]: Nucleus; mitochondria; chloroplast, Golgi, RER; SER; centrioles

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  1. Describe the fluid-mosaic structure of a cell surface membrane.(5/ marks): Phospholipids and proteins; Phospholipid bilayer; Arrangement of phos- pholipid molecules 'Tails to tails';'Floating'(protein) molecules / molecules can move in membrane;Intrinsic proteins extend through bilayer; Extrinsic proteins in outer layer only;(Ref. to intrinsic and extrinsic, unqualified, gains 1 mark);Detail of channel proteins / protein shapes / glycoproteins;Presence of cholesterol between phospho- lipids.
  2. Describe the part played by cell surface membranes in regulating the movement of substances into and out of cells.(6/10 marks): 1. Non-polar/lipid soluble molecules move through phospholipid layer/bilayer;2. Small molecules/wa- ter/gases move through phospholipid layer/bilayer;3. Ions/water soluble substances move through channels in proteins;4. Some proteins are gated;5. Reference to diffusion;6.Carriers identified as proteins;7. Carriers associated with facilitated dif- fusion;8. Carriers associated with active transport/transport with ATP/pumps;9. Dif- ferent cells have different proteins;10. Correct reference to cytosis;
  3. Describe the role of the enzymes of the digestive system in the complete breakdown of starch. (6 marks): 1. Amylase;2. (Starch) to maltose:3. Maltase;4. Maltose to glucose;5. Hydrolysis;6. (Of) glycosidic bond;
  4. Explain how the small intestine is adapted to its function in the absorption of the products of digestion. (6/9 marks) 1.: Large surface area provided by villi / microvilli;2. long / folds increase surface area / time for absorption;3. thin epithelium;4. short diffusion pathway;5. capillary network absorbs amino acids / sugars;6. lacteal for absorption of digested fats;7. Maintains a steep concentration gradient;8. mitochondria supply ATP / energy for active transport;9. carrier proteins (in membranes);
  5. Describe and explain the role of diffusion in the absorption of digested food by the ileum. (4 marks): 1. movement along / down concentration gradient;2. monoglycerides / micelles/fatty acids move into epithelial cells;3. monoglycerides move from epithelium into blood;4. chylomicrons move into lacteals / lymph;
  6. Describe and explain the role of facilitated diffusion in the absorption of digested food by the ileum. (3 marks): 1. movement along / down concentration gradient;2. reference to carrier / channel proteins;3. monosaccharides or named / amino acids move into epithelial cells;
  7. Describe and explain the role active transport in the absorption of digested food by the ileum.(4/6 marks): 1. movement against concentration gradient;2. energy / ATP required;3. reference to carrier proteins;4. monosaccharides or named / amino acids moved into epithelial cells;5. reference to co-diffusion e.g. glucose and NaCl;6. monosaccharides or named / amino acids move into blood

7 m/ m 21

  1. Explain mthe mimportance mof mmeiosis min mthe mlife mcycle mof ma msexually mreproduc- mingmorganism.m(4mmarks):m Meiosismhalvesmthemnumbermofmchromosomes; mRestoration mof mdiploid mnumber mat mfertilisation; mIntroduces mvariation;Correct mreference mto mnatural mselection m/ msurvival;
  2. Suggest mhow mthe mproportion mof mdividing mcells min ma mthin msection mcould mbe mdetermined.(3 mmarks): m count mcells musing mmicroscope; mcount mnumber mof mcells min mcell mdivision/where mchromosomes mvisible; mand mthen mthe mtotal mnumber mof mcells min mfield mof mview;
  3. Meiosis mresults min mgenetic mvariation min mthe mgametes mwhich mleads mto mvaria- mtion min mthe moffspring mformed mby msexual mreproduction. mDescribe mhow mmeiosis mcauses mthis mvariation mand mexplain mthe madvantage mof mvariation mto mthe mspecies. m(6/8 mmarks): m 1.mCrossing-over; m[IGNORE many mwrong mref.mto mtiming] m2.mIndependent / mrandom massortment m/ morientation m/ msegregation mof m(homologous) mchromosomes min mmeiosis mI; m3. mIndependent m/ mrandom massortment m/ morientation m/ msegregation mof mchro- mmatids min mmeiosis mII;m+ mAny mthreemfrom:m4.mDifferent madaptations m/ msome mbettermadapted; 5.mSome msurvive m/ mexample mdescribed;m6.mTo mreproduce;m7.mPass mon mgene m/ mallele;m8. mAllows mfor mchanging menvironment m/ mdifferent menvironment m/ mexample mdescribed;
  4. Describemwhatmhappens mto mchromosomes minmmeiosis.m(6 mmarks): m 1. mChromo- msomes mshorten m/ mthicken m/ mcondense; m2. mChromosomes massociate min mhomologous / m(described) mpairs m/ mformation mof mbivalents m/ mtetrads; m3. mCrossing-over m/ mchiasma mformation; m4. mJoin mto mspindle m(fibres) m/ mmoved mby mspindle;() m5. m(At) mequator m/ mmiddle mof mcell;() m6. m(join mvia) mcentromere m/ mkinetochore;() m7. m(Homologous) mchromosomes mmove mto mopposite mpoles m/ mchromosomes mseparate m/ mmove mapart; m(ALLOW m'are mpulled mapart') m8. m(Pairs mof) mchromatids mseparated min m2nd mdivision; m() mOR m" mindependent massortment"
  5. Ifmanmorganismmhasmamdiploidmchromosomemnumbermofm 28 m(2nm=m28)mhow mmany mchromosomes mwill mits mgametes mcontain? m(1 mmark): m 14
  6. Whatmismnon-disjunction?m(1mmark):m Failuremofmchromosomesmtomseparatemprop- merly mresulting min mdaughter mcells mwith mwrong mnumber mof mchromosomes
  7. Calculate mthe mpossible mnumber mof mdifferent mcombinations mof mchromosomes mfollowing mmeiosis m(without mcrossing mover) mif mparent mcell mcontains m 22 mchromo- msomes m(1 mmark): m 211 m= m 2048 mformula m2n
  8. Name mthe mlymphocyte mpresent min mthe mCell-mediated mresponse.: m T mlympho- mcytes
  9. Name mthe mlymphocyte mpresent min mthe mhumoral mresponse.: m B mLymphocytes
  10. Define mthe mterm mantigen: m An mantigen mis ma mmolecule m(usually mprotein) mthat mstimu- mlates man mimmune mresponse mresulting min mthe mproduction mof mspecific

8 m/ m 21 mantibodies.

  1. Describe mhow ma mmicrobe mcan mbe mbroken mdown mby mthe mprocess mof mPhago- mcytosis:m Pathogen mis mengulfed mby mthe mphagocyte.mForming ma mvesicle msurrounding

10 m/ m 21 msurrounding mtis- msue: m 1.Permeable mcapillary mwall/membrane;2. mSingle mcell mthick/thin mwalls, mreduces

11 m/ m 21 diffusionmdistance;3.mFlattenedm(endothelial)mcells,mreducesmdiffusionmdistance;4.mFen- mestrations, mallows msome mlarger mmolecules mthrough;m5.mSmall mdiameter/ mnarrow, mgives ma mlarge msurface marea mto mvolume/ mshort mdiffusion mdistance;6. mNarrow mlumen, mreduces mflow mrate mgiving mmore mtime mfor mdiffusion;7.mRed mblood mcells min mcontact mwith mwall/ mpass min msingle mfile, mgives mshort mdiffusion mdistance m/ mmore mtime mfor mdiffusion;

  1. Name mthe mmain mchambers mand mvalves mwithin mthe mheart: m Right mAtrium, mRight mVentricle, mLeft matrium, mLeft mVentricle, mAtrioventricular mvalves, mSemi-lunar mvalves.
  2. Explain mhow mtissue mfluid mis mformed mand mhow mit mmay mbe mreturned mto mthe mcirculatory msystem. m[5]: m 1. m(hydrostatic) mpressure mof mblood mhigh mat marterial mend;2. mfluid/water/soluble mmolecules mpass mout m(reject mplasma);3. mproteins/large mmolecules mremain;4. mthis mlowers mthe mwater mpotential m/ mwater mpotential mbecomes mmore mnegative m(inside mthe mcapillary);5.mwater mmoves mback minto mvenous mend mof mcapillary m(reject mtissue mfluid);6. mby mosmosis;7. mlymph msystem mcollects many mexcess mtissue mfluid;8. m(lymph) mreturns mto mblood m/ mcirculatory msystem m/mlink mwithmvena mcava/ mreturns mtissue mfluid mto mvein;
  3. Describe mthe mevents min mthe mcardiac mcycle m(6marks): m 1) mBlood menters matrium
  • mBlood mvolume mincreases mpressure min matrium- mPressure min matrium mgreater mthan min mventricl- matrioventricular mvalve mopens. m- mAtrium mmuscles mcontract- mFurther mincreases mpressure- mRemaining mblood mforced minto mventricles2) mBlood menters mventricle- mincrease min mvolume mof mblood mincreases mthe mpressure min mthe mventricles- mPressure min mventricle mgreater mthan min matrium- matrioventricular mvalve mcloses. m3) mVentricle mmuscles mcontract- mincreasing mpressure mfurther min mventricle muntil mgreater mthan min maorta/ mpulmonary martery- mSemi mLunar mvalve mopens.- mBlood menters maorta/ mpulmonary martery- mBlood mis mpumped mto mbody m(left) mor mlungs m(right)4)mVentricle mmuscles mrelax- mPressure min mventricle mis mless mthan min maorta/ mpulmonary martery- mSemi mlunar mvalves mclose
  1. How mis mthe mcardiac mcycle mcontrolled? m(6marks): m (SAN) mmyogenic; mElectrical mImpulse m(spreads mover matria mand) mproduces matrial mcontraction;mDelay mat mAVN;mElectri- mcal mimpulse mis mprevented mfrom mpassing mto mthe mventricles mby mnon- conducting mtissue mAllowing matria mto mempty mbefore mventricles mcontract; mImpulse mto mbase mof mventricles; mContraction mof mventricles mfrom mbase mup
  2. Describe mand mexplain mthe mmechanism mthat mcauses mforced mexpiration. m( mmarks): m 1. mContraction mof minternal mintercostal mmuscles m2. mRelaxation mof mdiaphragm mmuscles/Relaxation mof mexternal mintercostal mmuscles;m3.mCauses mdecrease min mvolume mof mchest/thoracic mcavity; m4. mAir mpushed mdown mpressure mgradient;
  3. Describe mand mexplain mhow mthe mlungs mare madapted mto mallow mrapid mexchange mof moxygen mbetween mair min mthe malveoli mand mblood min mthe mcapillaries

13 m/ m 21 (So) mfast mdiffusion;8mVentilation m/ mcirculation;m 9 mMaintains ma mdiffusion m/ mconcentration mgradient;

  1. Explain mhow mtwo mfeatures mof mgills mallow mefficient mgas mexchange.: m Fila- mments/lamellae mprovide mlarge msurface marea;mThin/flattened mepithelium/ mone/two mcell mlayers mso mshort mdiffusion mpathway m(between mwater mand mblood); mCountercurrent/blood mflow mmaintains mconcentration/diffusion mgradient;
  2. Describe mhow mthe minsect mis madapted mto mensure mminimal mwater mloss mand mex- mplainmhowmthesemadaptationsmhelpmminimisemwatermloss.m(4mmarks): m 1 mExoskeleton / mcuticle m/ mouter mcovering mof minsect; m 2 mis mwaterproof;3 mInsect mhas ma msmall msurface marea mto mvolume mratio; m4. mwhich mreduces mthe marea mover mwhich mwater mcan mbe mlost; mSpiracles mcan mbe mclosed; m 6 mto mprevent mwater mloss mfrom mthe mspiracles;
  3. Explain mhow ma mconcentration mgradient moccurs mand mhow mthis mensures meffi- mcient mgas mexchange min minsects m(3 mmarks): m 1. mRespiring mcells muse mup moxygen; m2. mOxygen mconcentration mdecreases mtowards mthe mend mof mthe mtracheoles; m3.mSo moxygen mdiffuses mdown ma mconcentration mgradient mfrom mthe mtracheae malong mthe mtracheoles mto mthe mrespiring mcells.
  4. Haemoglobin mis mdescribed mas ma mquaternary mprotein, mwhat mis mmeant mby mthis?: m composed mof mfour mpolypeptide mchains, meach mcontaining ma mhaem mgroup.
  5. Describe mhow mthe mstructure mof mhaemoglobin mmakes mit meffective min mthe mtrans- mport mof moxygen. m(4 mmarks): m quaternary mstructure, mhaem mgroups mbind moxygen, mfour mpolypeptide mchains mso mfour mhaem mgroups m,one mhaemoglobin mmolecule mcan mbind m 4 moxygen mmolecules m/ m 8 moxygen matoms m,Bohr meffect m/ moxygen mrelease min mthe mpresence mof mcarbon mdioxide/acidic mpH
  6. Describe mhow mhaemoglobin mis minvolved min mabsorbing moxygen min mthe mlungs mand mtransporting mit mto mrespiring mtissues. m(6 mmarks m): m 1. mdiffusion mof moxygen minto mhaemoglobin min mred mblood mcells; m2. mhigh maffinity mof mhaemoglobin min mhigh mpartial mpressure mof moxygen m3.mloads m/ mbecomes msaturated min mlungs m/ mat mhigh mppÓ moxygen; m4. moxyhaemoglobin mformed; m5.munloads m/ mlow maffinity min mlow mpartial mpressure mof moxygen; 6.mrespiration min mtissues mgives mhigh mCÓ mconcentration m/ mhigh mtemperature/ mhigh mH+ mconcentration m/ mlow mpH m7. mdissociation mcurve mshifts mto mright m/ m8. moxyhaemoglobin mdissociation mat mhigher mpartial mpressure mof mcarbon mdioxide.
  7. During mexercise mthe moxygen-haemoglobin mdissociation mcurve mmoves mto mthe mright, mdescribe mthe madvantage mof mthis mchange: m (Haemoglobin) mreleases mmore moxygen; mFor mrespiration;mThe mtissues mof ma mmouse mhave ma mhigher mrate mof moxygen mconsumption mper mgram mof mbody mtissue mthan man melephant.
  8. Sketch mthe moxygen mdissociation mcurve mfor mboth manimals mand mexplain mthe

14 m/ m 21 madvantage mof mthe mposition mof mthe mmouse mcurve.: m Both mcurves mdrawn mas msigmoidal mcurves mwith mthe mmouse mto mthe mright. m(at mthe mtissues mat mlow mpp moxygen) mthe mmouse mhaemoglobin mis mless msaturated mwith moxygen m/ mhas mreduced maffinity; moxyhaemoglobin

16 m/ m 21 m 1. mHelicase; m2. mBreaks mhydrogen mbonds; m3. mOnly mone mDNA mstrand macts mas mtemplate;

  1. mRNA mnucleotides mattracted mto mexposed mbases; m5. m(Attraction) maccording mto mbase mpairing mrule; m6. mRNA mpolymerase mjoins m(RNA) mnucleotides mtogether; m7. mPre-mRNA mspliced mto mremove mintrons.

17 m/ m 21

  1. How mare mnew malleles mof ma mgene mproduced? m(1 mmark): m Mutation
  2. What mis mdirectional mselection? m(1 mmark): m Selection mfor mONE mextreme/mean mshifts mover mtime
  3. Explain mhow mantibiotic mresistant mstrains mof mbacteria mare mproduced? m( mmarks): m Mutation moccurs mproducing mresistance mallele, mbacteria mwith mthis mallele msurvive mand mreproduce, mpassing mon mthis mallele. mFrequency mof mallele mincreases mover mtime.
  4. What mis mgenetic mdiversity? m(1 mmark): m All mthe mdifferent malleles mof mall mgenes min ma mpopulation
  5. What mtype mof mvariation mis mshown mby mhuman mheight? m(1 mmark): m Continuous mvariation m- mrange mof mvalues/not mdiscrete mcategories/ mmany mcategories/no mgaps;
  6. Give mtwo mpossible mcauses mof mthis mvariation mthat mresult mfrom mmeiosis mduring mgamete mformation.(2 mmarks): m Crossing mover m/ mchiasmata; mRandom msegregation m/ mindependent massortment; mIn mmeiosis mI mand mmeiosis mII;
  7. When mcomparing mvariation min msize mbetween mtwo mgroups mof morganisms, mit mis moften mconsidered mmore museful mto mcompare mstandard mdeviations mrather mthan ranges.mExplainmwhy.(2mmarks):m Rangeminfluencedmbymsinglem'outlier'm(acceptmanom- maly) m/ mconverse mfor mS.D.; mS.D. mshows mdispersion/spread mabout mmean; mRange monly mshowsmhighestmandmlowestmvalues/extremes;mS.D.mallowsmstatisticalmuse;mTests mwhether mor mnot mdifferences mare msignificant;
  8. Describe mhow myou mwould minvestigate mthe meffect mof mantibacterial mchemicals monmthemgrowth mofmE mcolim(6 mmarks): m Aseptic mtechnique/sterile magar mplate, mflame mneck mof mculture mbottle;mSpread mplate/controlled mvolume mof mbacteria mtransferred mto mplate mand mspreadmequallymacross mthemsurface;mControlledmvolumemof mantibacterial mchemicalmonmto mfiltermpapermdisc;mDisc mplated mon minoculated magarmplate mand mincubated matm 25 mdegrees mC mform 2 mdays;mDiameter mof mthe mzone mof minhibition mmeasured;mRepeat mmeasurements mand mmean mcalculated;mStudentmTmtest mto minvestigate msignificance mof many mdifferencembetween mmeans.
  9. Give mthe mhierarchical morder mof mtaxa min mour mclassification msystem m(1 mmark)- :m Domain, mkingdom, mphylum, mclass, morder, mfamily, mgenus, mspecies
  10. How mcan myou mtell mif mtwo morganisms mbelong mto mthe msame mspecies mgrouping? m(1 mmark): m Reproduce mand mproduce mfertile moffspring
  11. Which mgrouping mdoes mthe mfirstmname minmanmorganism's mbinomial mname mgive myou? m(1 mmark): m Genus
  12. What mdoes ma mphylogenetic mtree mtellmyou?m(1 mmark): m How mrecentlymtwo mspecies mshared ma mcommon mancestor
  13. Give mthree mways min mwhich mcourtship mbehaviour mincreases mthe mprobability mof msuccessful mmating.m(4 mmarks): m 1.mRecognise m/ midentify m/ mattract

19 m/ m 21 sex;4. mIndication mof m(sexual) mmaturity m/ mfertility m/ mreceptivity m/ mreadiness mto mmate;5. mFormation mof ma mpair mbond m/ mbond mbetween mtwo morganisms m(to mhave m/ mraise myoung).

  1. Describe mhow myou mwould mcalculate m% mchange: m Change m/ moriginal mx
  2. Which mstatistical mtest mdo myou muse mif myour mdata mis mcategoric? m(i.e. mfalls minto mseparate mcategories mlike mpink mand mwhite mflowers): m Chi msquared
  3. Which mstatistical mtest mdo myou muse myou mwant mto mcompare mtwo mmean mvalues mtomsee mifmtheymaremsignificantlymdifferentmfrommeachmother mormnot?: m Student'smTmtest
  4. Which mstatistical mtest mdo myou muse myou mwant mto msee mif mthere mis ma msignificant mcorrelation mbetween mtwo mvariables?: m Correlation mcoefficient
  5. Write ma mparagraph musing mthe mterms mprobability mand mchance mif mthe mdifferent mor massociation mfrom mstats mresults mat mP m0.05 mhas ma mcalculated mvalue mgreater mthan mthe mcriterial mvalue.: m The mprobability mof mthe mdifference mor massociation mbeing mdue mto mchance mis mless mthan m5% m;mTherefore mthere mis ma msignificant mdifference mor massociation mbetween mthe mtwo mmeans/variables
  6. Write ma mparagraph musing mthe mterms mprobability mand mchance mif mthe mdifferent mormassociationmfrommstatsmresultsmatmPm0.001mhasmamcalculatedmvalue mgreatermthan mthe mcriterial mvalue.: m The mprobability mof mthe mdifference mor massociation mbeing mdue mto mchance mis mless mthan m0.1% m;mTherefore mthere mis ma msignificant mdifference mor massociation mbetween mthe mtwo mmeans/variables
  7. Describe mhow myou mwould mcalculate mdry mmass: m Heat mat m100°C m/ mheat mto mtemp mto mevaporate mwater; mWeigh mand mheat muntil mno mfurther mchange min mmass;
  8. Suggest mwhy mwe mcalculate mdry mmass: m Amount mof mwater mpresent mwill mvary; mThis mwill maffect mfresh mmass m/ mwill mnot maffect mdry mmass;
  9. Describe mhow myou mwould muse ma mcolorimeter mto mwork mout man munknown mconcentration musing ma mcalibration mcurve: m Make msolutions mof mknown/different mcon- mcentrations;mUse mcolorimeter mto mmeasure mabsorbency mvalue mof meach msolution mand mplot mcalibrationmcurve/graphmdescribed;mTreatmthemunknownmsampleminmthemsame mwaym(same mvolume mof mindicator metc); mFind mconcentration mof msample mfrom mcalibration mcurve;
  10. Explain mhow myou mwould mcalculate mthe mvolume mof ma msphere: m Measure mthe mradius m; mRepeat mand mcalculate ma mmean mradius mUse mformula m=4/3 mrÀ^
  11. Explain mwhy mwe mcollect ma mlarge mnumber mof mresults: m allows manomalies mto mbe midentified m/ mincreases mreliability m(of mmeans m/ maverages m/ mresults); mallows muse mof mstatistical mtest; meffect mof mvariation min mdata mto mbe mminimised;
  12. Genetic mdiversity mcan mbe mcompared mwithin, mor mbetween mspecies mby minvesti- mgation mof? m(3 mmarks): m DNA mBase msequences, mamino macids msequences, mimmunolog- mical mcomparisons

20 m/ m 21

  1. When mcollecting mvariation mdata mhow mdo mwe mensure mit mis mreliable? m(1 mmark)- : m Large mand mrandom msamples mtaken/ mmean mSD mcalculated