Spm 4551 2006 Biology k2 Berjawapan

8/2/2019 Spm 4551 2006 Biology k2 Berjawapan

1/15

Section A[60 marks]

Answer all questions in this section.1 Diagram 1 shows a plant cell as seen under an electron microscope.

Diagram IOn Diagram1, abel the structuresp,e, R andS.State the function of structure:

(a) (i)(ii)

[4 ntarksl

P:

Q:

12marl--\./(b) Explain the role ofR to maintain cell turgidity.

[2marks]

SPM 2006 BIOLOGY P2


2/15

(c) Every somatic cell which contains structure e has a potential to formorganism.(i) Namethe techniqueused o prodi.rce ewplants in largequantities.

a complete new

IImarkl(ii) By using onesuitablepart of the plant, explain the technique n (cxi).

[4marksl(a) Diagram2.1showshumandigestivesystem.

Duodenum

Diagrarn 2.1structure Q in Diagram2.Lis involved n the digestionoffat.(i) Namestructure Q.

[lmarkl


3/15

(ii) Namethe enzlrmewhichdigests at in e.

ILmarhl(iii) Diagra m2.2showsa mechanismof an enzyme eaction.Dray the diagram in the spaces II and fV provided in Diagram 2.2 to complete hemechanismof the enzJrmeeaction.

I IIIDiagram2.2

(b) (i) Explain how starch s digestedn the duodenum.12marks)

B n+flVv

(ii) Astudent eats oomanyoranges.Explain the effect of eatfng too many oranges onduodenum

[2marksfthe digestion of starch in thY

12m,arksl


4/15

(c) In a food preparation process,a houservife carries out the following steps:step 1 : Marinate piecesof meat with strips of unripe papaya in a uarln.Step 2 : Immerse the basin in a'eontainei frlled with watei at 40 "C for B0 minutes as inDiagram 2.3.

Water at 40"CMixture of pieces of meatwith strips ofunripe papaya

Diagram 2.9Explain why the housewifecaries out Step 1and Step2.

14markslI Diagram 3.1 shows a crosssection of part ofthe nervous sistem.

IIIx ---!

I.l

(a) (i) NamestructureX.

lLmarkl(ii) Statethe functionofX.

ILm.arkl


5/15

(b) (i) Why is Y swollenat the dorsalroot?

(ii) Complete Diagram 3.1 with the neurones involved in a reflex action.directionofthe impulsemovementon the neurones.(c) compare two structuresof a sensoryneuroneand a motor neurone.

1.

ILmarkTMark the[2marksj

2.

12marh^l(d) If the spinal nenre s cut offat Z,whatis the effecton the organwhich is connectedo it?-Explainyonranswer. .

12m.arksl(e) Ali's finger accidentlytouchesa flame.Explain brieflyhow his reflex action functions to avoid the injury.

13marksl


6/15

4 Diagam 4 showsa longitudinal sectionof the reproductiveparts of a flowerduring fertilization.

(a)(b)

Diagrarn 4On Diagram4, name he structuresp, e, R and S.(t In the spacebelow,draw a seition through the ovule,showingall the cells n S.Label the cells involved in fertilization.

(ii) What is tbe significanceof having two Q structures in the fertilization?

V*ornf,

[3 marks]

(c)IZmarks]

In Diagram4, thestructureY has to be kept dormant for future researphpurposes.(t ExplainhowY canbeprevented rom germinating.

14712marksl


7/15

(ii) If Yis tobe germinated,suggestone method o stimulate the germinationof y.

ILmark]Diagram 5'1 showsa sequence f stages n the synthesisof an extracellular eRzJrmen a humanancreaticcell' The stagesare labelled as Staie r, Stage rr and Stage rrl. StageI showsahange in the specific part of a DNA stran*d. trre,n-Ng strand in=volved ontains threeitrogenousbases,CTC.

Diagram 5.1(a) Explain the changesthat occured n the double helix of the DNAstrand during stage I.

12rnarksl(b) BasedonDiagram5.1:

(i) state two differencesbetween he structure ofthe protein polypeptidemorecure nd theDNAmolecule. rvrr'.vv1.

7GX -stase;"",)(:"r,",ffilTft'"[#\ FiT, \ \ ,r\ into the cytopla" ,/cteusg] ,/ Y ProteinKv-',,t;a,ucreus, / u1 ;"";; Kw"pt*. I \ beingsynthesised

\ ^io"r",J*,"*\f *o*"y/

2.

149[2rnarks]


8/15

(c)

(ii) Ditrerentiatebetrareenhe structure of DNA and RNA.

[lrnark]Explain how the protein formed at the ribosome is transformed into the extracellularenzyme so that it can be secretedfrom the cell.

(d) Diagram 5.2 shows a gene mutation that occurs in the DNA strandsequenceCTC.Before mutation

DNAstrand

Synthesizedprotein

t r r lTC,lotamic acidDiagram 8.2

Explain how the mutation affects he specificcharacteristicor trait controlled.

tS narkq_,containing the base

r t l C ACI+oValinelu

Aftermutation

15113marksl


9/15

Section B120marksl

Answer any one question.Diagram6 shows hreeorganisms,p, e and R.

ilF-";t$o*"-P R

Diagram 6Describehe typeof nutrition in pand e. 14marksl(a) (i)

(ii1Explain one similarity and four differencesbetweenthe alimentary canal of e and R.ILOmarks)(b) constipation, night blindnessand anaemiaare three health problems.

State the causeand suggest he ways to overcome hesehealth problems rom nutritionalasPects. [6marks)(a) Plasma membrane encircles the protoplasm of a cell. As a whole plasma membraneexhibits fiuidity as f it is a layer of oil in a beaker ofwater.

what is meantbyplasma membrane exhibits fluidity? [4marksl(b) (i) An experiment s carriedout usingsubstanceR outsidea cell.

The aim of the experiment is to study the effect of different concentrationsof substanceR on the rate of ts movementacrosshe plasmamembrane nto the cell.

-


10/15

Graph 7.1shows he result of the experiment.Rate of movementof substance R / mg s-1

Concentration ofsubstance R/ unit

Graph 7.1Basedon Graph 7.1, state an exampleof substanceR and explain how substuo"" *-movesacrosshe plasmamembrane. 16m,arksl

155


11/15

(ii) The experiment s repeatedby replacingsubstanceRwith substance .Graph7.2showshe resultobtained.

Rate of movementof substanceS / mg s-r

Concentration ofsubstance S / unit

Graf 7.2Based on Graph 7.1 and Gr apn 7 2,compare and explain the movement of substancil Rand substance S acrossthe plasma membrane. [L0 marksl

t57


12/15

Section C[20 marks]

Answer'any one question.Green plants sJmthesize their food through the process of photosynthesis. The chemicalprocess of photosynthesis can be summarised as in the schematic diagram in Diagram 8.

Hidroxyl ion

Lightt"r.rr""IWater + Oxygen

Water molecule

Chlorophyll rrrolecule ------+ Electron

Hydrogen

Dark reactionstored Glucose+- (CHrO)n Carbondioxideater

Diagram 8(a) State the meaningof photos5mthesisbased on the schematic diagram in Diagram 8.

. t2 marksT(b) Starting with water and cbrbon dioxide as the raw materials, describe how a green pladproduces starch molecules tg ma;i,,-_(c) It is found that the processof photosynthesis contributes to the balance of nature.

Explain how air pollution may have an effect on photos5mthesisand the balance of nature.t10 marks]

I (a) The following statements are on lymphatic system and blood circulaiory system.' llhe substances that come out from the blood capillaries into the body tissue will be re-entered into the blood circulatory system.o Lymphatic system also functions in transporting products of digestion.Explain the above statements to justifr that lymphatic system is a complementary to theblood circulatory system. ILOmarksl

[-

159


13/15

Multicellular organisms like humans, need specific transport systems as comparedto unicellular organisms likeAm oeba sp.,which do not ""J;1;;;"";;;;;-*.Give an evaluation of the above statement based on the physical features of the organisrnswith the following physiological processes:RespirationNutritionExcretion

[L0 marks]

t6 l


14/15

Conclusion: Isotonic solution will maintain themass and the length of plant tissues and this is yo/o fsucrosesolution.SPM D(AMINATION PAPER 2006Paper IlC 2C7B 8A13A 14 D19D 20 C25 D 26 B31D 32 A37 B 38C43D 44 D49 C 508Paper 2Section A1 (a) (r) chloroplastnucleusvacuoleGolgi apparatusContains chlorophyll whieh absorbs

sunlight for photosynthesis.Contains genetic material in the form ofchromosomeswhich control the activitiesofthe cells.The vacuolepushesthe cytoplasm and presses heplasma membrane against the cell wall.(l) fissueculture/cloning(ii) - Tissuesectionsareobtainedfromtheroot.- Tissues are cultured in suitable nutrientmediums with growth hormones.- Callus tissues are formed through mitosis.- Callus tissues are transfetred to agarmedium.- New plantlets/clones formed are thentransfened and grown in the soil.Small intestine/ileumLipase

(b) (t - Pancreassecretespancreaticjuiceintotheduodenum.- Pancieatic juice contains amylasewhich hydrolyses undigested starch intomaltose.(il) - Oranges contain ascorbic acid and willlower the pH in the duodenum from anoptimum of pH 3.- fhis will slow down the digestion of starehwhich requires an optimum pH of 7.t-8.2.(c) - Step 1 is to provide enzyme protease to digestthe meat in order to tenderize the meat.- Step 2 is to provide the optimum temperaturefor enzyme action and to allow enough timefor enzyme reaction.

Spinal cordControl reflex actions and connect the brainto the peripheral nervoussystem.Congregation of cell bodies of afferentneurones o form a ganglion.

3 (a) (,(ir)o)( '

(ir)3C 4A 5A 689C 10D 1lA 12 C15c16At7A18B2r B 22 B 23 C 24 B

27 C 28 A 29 A 30A33B 34 A 35D 86839A 40 B 4r D 42D45 D 46 D 47 A 48 C(c) Sensory neurone Motorneurone

1. Cellbcdylocatedoutside the spinalcord.1. Cellbodylocatedinside the spinalcord.

2. Has a longdendron and ashort axon.2. Has a shortdendron and along axon.

Nerve impulses cannot be transmitted from thespinal cord to the effectors and the organ will notrespond.- Pain receptors in the skin ofthe fingers detectstimulus- Nerve impulses are transmitted from receptorsto spinal cord via sensory neurone whichtransmits impulses to the efferent/motornenrone via interneurone and then to musclesin the organ which contracts and pulls handawayfromflame.

PaRsPa

(ir)(d)

(e)o)(c)

2 (a) (D(ii)(iir)

4 (a)(b)

pollen tubeovary

P:R:(r)

Q : male gametesS : embryo sacs

ry

Polar nucleus

Eggcell/ovum(ri) - One male gamete fuses with the egg cell.- Another male gamete fuses with the two

polarnucleus.- Double fertfisation occurs.(r) Place in dry/cool plabe which is air tight(ii) Place in sugar solution- The double helix of the DNAstrand unzips.* The DNA code is copied/transcribed into astrandof mRNA.(t 1. DNA is double stranded whereaspolypeptide is single stranddd2. DNA is made up of repeating units ofphosphate, sugar and nitrogenous bases(nucleotides) whereas polypeptide is

(c)

(a)

tl

(b)


15/15

ffff "r of 20 different ypeof amino(ii) DNA molecules consists of 2 polynucleotidestrands whereas RNAconsists of a singlestranded nucleotide.(c) Proteins synthesized at the ribosome enters thecistern/spaee in the endoplasmic reticulum whichis transported to the Golgi apparatus in transportvesicles. The Golgi apparatus process,modify andpackage the enzymes into vesicles and are secretedfromthe cell.(d) This is a substitute mutation where the aminoacid valine replaces glutamic acid. The aminoacid sequence n the polypeptide is altered. Thischanges the structure ofthe protein which loses itsoriginal function.

B(a) (t P: AutotrophicQ: Heterotrophic(ii) SimilarityBoth contain anaerobic bacteria andprotnzna in their alimentary' canal fordigestion of cellulose.Dififerenees

Q has a very large caecumcompared o R.- Q has one stomach and R has fourstomaches; rumen, reticulum, omasumand abomasums.- R has a diastema to store cut cellulosebefore chewing by the molar.R has a hard upper palate to help in thecutting ofcellulose.(b) Constipa.tion- Insufficient fibre in the diet- Eat more vegetables and fruitsAnaemia- Insufficientiron/ferum- Eat more red meat, liver, spinach and efgsNightblindness- Insu{ficientvitaminAEat more liver and eggyolks

(a) Plasma membrane consists of a bilayer ofphospholipid with globular proteins interspersedin it. The phospholipid layer and able to movetherefore it exhibits fluidity.(b) (t Substance R is water molecules. Water.molecules can difftrse through a plasmamembrane because the size of the watermoleculesare small.(ii) Substance S is sofium ions/calcium ions. Thetransport of sodium ions is active transportwhere there is movement of molecules orions from a region of lower concentration toa higher concentration across the plasmamembrane with the use of cellular energ:y.However the movement of substance R does

not require enerry and it is called osmosis.The process of osmosis ddes not requireenerg:y as water molecules move across a

Section C8 (a) Sunlight is absorbed by chlorophyll to break upwater to provide H atom and form AIP which areused o reduceCO, to form starch.@) During light reaction, chlorophyll captures lightenerg'y which excites the electrons of chlorophyllmolecules to higher energ'y evel. In the excitedstate, the electrons can leave the chlorophyll' molecules. Light energy is used to split HrOmolecules into hydrogen ions (H*) and hydroxyl

ions (OH-). The OH- from photolysis of watercombine to form water and orygen gas. Duringthe dark reaction, the hydrogen atoms are usedto fix CO, in a series of reactions catalysed byenzymes. The overall reaction results in thereduction of CO, into glucose. The glucosemonomers undergo condensation to form starch.(c) Incomplete combustion of fossil fuels producestiny carbon particles which form smoke, hazeand smog. Smoke and haze r"educe lightintensity. Smoke particles can also deposit onleaves and prevent gaseous exchange. Both canlower the rate ofphotosynthesis.

9 (a) lO% of interstitial fluid enters ly.mphaticcapillaries to form lymph, and flows into biggervessels called lymphatic vessels which conaectthe right lymphatic duct and the thoracic duct.Both push their contents into the right and leftsubclavian vein and return the fluids into the bloodcirculatory system via the lymphatic systems.Fatty acids and glycerol diffirse into thelacteal in the small intestine. It is transported tothe thoracic duct, left subclavian vein andjoins theblood circulatory system.(b) Respiration- Gaseous exchange takes plaee by diffr.rsionacross the thin plasma membrane.- Has a relatively large surface area compared tothe volume.- Simple diffirsion is sufficient to transport thegases nto, around and out oftheir bodies.- Oxygen diffuses into the cell and carbon dioxidediffirses out of the cell due to concentrationgradients.Nutrition j- Amoeba engulfs microorganisms such as. bacteria by carrying out phagocytosis.- Protrusions of the cyrtoplasmorms pseudopodiawhich surround thd inuscles which is broughtby food vacuole.Enzlrmes are secreted into it and digestionoccurs.Excretion- Undigested food or waste products are excretedby exocytosis.- The vacuole fuses with the plasma membrane.- Its contents are then excreted when the

membrane burst opento the exterior.Paper 3

Documents

Spm 4551 2006 Biology k2 Berjawapan