spm 4551 2007 biology k2 berjawapan

8/2/2019 Spm 4551 2007 Biology k2 Berjawapan

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!.n to thehreeo*ect#t1'o"'f"tft'" gmFl** n"ffiu in able.il Ih3??d" (v) bggl tiga fungsi organ X ying b-etul,d.alampitak-petak yang d,isediakandalamJadual t.[3 tnark][3 rnarkahl

(b) Erector muscle s a tissue.State reasons why X is classified as an organ and erector muscle is classified as atissue. -- - --o---Otot regang ialah tisu.Nyatakan sebabnxengapa. d'iketaskansebagaiorgan d,an ototregangsebagai tbu.X:

[2 marks]12markahfk) Jlre following information shows:o-ol" of the organ systems found in the human body.Maklurnat berikut menuniukkan beberapoorgoi yang terd,apatd.atambadan manusia.fick (rz) the two systems which contain orgrnX, in the boxesprovided below.Tandn(/) basi d'uasistemyang mengand.uogiorgonX"d.alampeiak-petakyang d,ised,iakandi bawah.

| | Blood circulation system/Sjs empered,aran d,arahRespiratorysystenr/Si tem respirasiIntegumentary systeml Sistemntegum,enExcretorysystem/Slsemperku,muhan

Itln

Erector muscleI Otot regang:

[2 marksf(d) Human body temperature is maintained at BZ oC.Suhu badan manusia dikekatkan pad.a g7 "C.

Explain the roles of the erector muscle, hair follicle and'sweat gland in maintaining thebody temperature on a hot day.Tbranghctnperanan otot regang, bulu rorna d,an kelenjar peluh d.alam mengekalkan suhubadan pada hari yang pa,nos. : ' -----:

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SPM 2007 BIOLOGY P2 Question No 1 at the last page.


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Erector muscleI Otot regang:

Hair follicle I Bulu ron'La:

Sweat gland I Kelenjar peluh:

tBmarksl[3markahlDiagram 2.1 and Diagram 2.2 show two different types of movement of substances acrossthe plasma membrane.Rajah 2.I d.an Raiah 2.2 rnenunjukkan dua jenis peigerakan yang berbeza bagi bahan

Diagram 2.1Rajoh 2.1

DTagrarn 2.2Rojah 2.2

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m,erentasi membran plasnt a.Substance

lc Bahan -----\" uo ! -ttg

SubstanceBahon -----?".r""1 "tf": @'@o'1"" Outsidethe cell'Luar selo o0aofATi O


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(a) In Diagram 2.1, label the following structures:Pada Rajah 2.1, Iabel struktur-struktur berikut:Phospholipidbilayer, with letter JDwilapisan fosfolipid.,dengan huruf JCarrier protein, with letter KProtein pernbawa,d,enganhuruf K

[2 rnarks]12 markahl(b) state two characteristicsof the phospholipidbilayer.Nyatakan dua ciri dwilapisan fisfotipid. '

[2 rnarksl[2 rnarkah]I"9. the process of the movement of substances across the pldsma membrane as shownin Diagram 2.1and Diagram 2.2.Namakan prosespergerakan bahan merentasi membran plasma yang d,itunjukkan padaRajah 2.I dan Rajah 2.2.Process n Diagram 2.L I prosespad,a Rajah 2.I

Process in Diagram,2.Z I prosespad,a Rajah 2.2

1.2"

(c)

[2 marksl12rnarkahl(d) (t Glucosemoleculesare transpo"tq airos: the plasma membrane nto the cell throughthe proces"_"!oytt in Diagram 2.L. Explain *fryMolekul-molekulglukosa ilianghut ke iet merentasimembianplasma melalui prosesydng ditunjukkan pad,aRbjoh 2.L. Terangh:a,nnengapa.

,r'#:#;l(iil If the substances in Diagr am 2.2 are calcium ions, describe ho* they are transportedinto the cell.Jiha bohan pada Raiah 2.2 ad'alah ion-ion halsiurn, huraikan bagaimana ion-ionkalsium tersebut diangkut ke d,a,Iamsel.

195[4,marksl14rnarkahj


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Diagram 3.1 shows hree stagesof mitosis, R Q and R, in an animal cell'Rajih 3.L menunjukkan tiga peringkat mitosis,E Q dan R, dnlarn sel haiwan.

Diagran 3.1Raiah 3.LName the stagesR Q and R in the spacesprovided in Diagram 3.1.Namakan peringkat 4 Q dan R datarn rucrngydng disediakan dalam Raiah 3-L.

tB marksl13marhahlExplain what happensat stage Q.Teranghanapa ycnl,gberlaku pada peringk'at Q.

[3 rnarks][3 markah]State the chromosome behaviour at the followirrg stages:Nyatakan perlakuan kromosom pad'a peringkat berikut: 'StagePlPer ingkatP

(a)

(b)

(c)

2^N>rt..a- r' ((,D

StageF' lPer inghatR

[2 marks]12ma,rkahJ

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(d) Explain the importance of mitosis in the process of cloning orchid plants.Terangkan kepentingan rnitosis d.aram pr6r", pengklonan lokok oriia.

[3 rnarhs][3 markah](e) Di4gram3.2 shows a cell at stage P. In the next stage, t is found that chromosomeMrs not separated.Rajah 3'2 rnbnunjukkansuatu selpad,aperinghat P. Pad,aperinghat seterusnya, .id.apatikromosomM tidak berpisah.

ChromosomeMKromosornM

Diagrarn 3.2Rajah 3.2-Completethe diagrams for the two daughter cells which will be formed in the space providedIDelow.Lenghapkan raiah kedua-d'ua sel anak yang akan terbentuk pad,a ruang yang d.ised.iaitznnibawah.

Daughter cell 1 | Selanak 1 Daughter cell2 | Sel,anah212marksl[2marlnhl

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Diagram 4.1 shows a nucleotide from a DNA molecule.Rajah 4.1 menunjukkan satu nukleotida daripada satu molekul DNA.

PentosesugarGuIaPentosaDiagram 4.1Rajah 4.1

(a) Name the structures P and Q.Narnakan struktur P dan struktur Q.Pia:

(b) A DNA molecule consists of two nucleotide chains.Complete Diagram 4.2 to show a DNA molecule.Part of one of the nucleotide chains has been drawn.Satu molekut DNA terdiri daripada dua rantai nukleotida.Lengkapkan Raiah 4.2 untuk rnenuniukkan satu molekul DNA.Sebahagian daripada satu rantai nukleotid,a itu telah dilukishan.

Diagram 4.2Rojah 4.2

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[3 marks]13markahl1.98


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(c) In Diagram 4'3, A, B, c, d dan E- represent the genes found on a chromosome. After acertain treatment, gene A is found missing. -- 'Pada Raiah 4'3, A, B, c, d d,an E rnewg'kit7gen-gen yang terd.apatpad.a suatu kromosom.Selepas suatu rawatan tertentu, gen'A didapati hilang.

(tDiagram 4.8

Rajah 4.8{"*" the process that has taken place on the chromosome.Narnakanprosesang terahberraiu pada,n o*ito* ili.- -

B

cd

E

IL mark]IL markahl(ii) Name one factor that causes he process n a(cXi).Narnakan satra ahtor yang menyebabkoopror"i'd.i ak)G).

lL markllL markahl(d) Diagram 4.4 shows the karyotype of an individual.Rajah 4.4 rnenunjuhhan nalioiii seordng ind.iuid,u.

nffiu illlllilffiililrf ffi78910ri : . :f t i l00 lI ilf rr13It19

154 16 77 18rI20 l l r2L

Diagram 4.4Rajah 4.4199

IT22 trx


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(r) Determine the sex of the individual.Terutukanantina indiuidu itu.f7 mark)IL markah]

(ii) Name the genetic disease suffered by the individual'State.a reason.Namakan penyakit genetik yang d,ihidap oleh indiuidu itu.Nyatakan sebab.Disease I Penyakit:

Reason I Sebab:[2 marks]12markahl

(e) Diagram 4.5 shows the cross breeding between two mice.Rajih 4.5 meinuniukkan kacuk silang antara dua eko,r tikus.

Homozygous lack furHomozigotberbuluhitam Homozygouswhite furHornozigot berbulu putih

OffspringAnakBlack furBerbuluhitam Black urBerbuluhitarn

Diagram 4.5Raioh 4.5

Black furBerbuluhitam Black furBerbulu hitam


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Explain why atl of the o{fripringhave black fur.Tbrangkantnengcrpa enl,uaanak tikus itu berbulu hitam.

[2 marks][2 marhah]5 Diagram 5'1 shows he humanvertebral column.Diagram b.2shows he two typesof vertebrae,R and T in the human vertebral column.Raiah 5'1 menunjukkan urus uertebramaruusia.Raiah 8.2 menunjukkand,uaenis uertebraR dan T, dalam turus uertebramanusia.

Diagram 5.1Rojah 5.L(a) Name the vertebrae.Narnakan uerteb a-uertebra itu.

Diagrarn 5.2Rajah 5.2

#h'-da-'a.---..s,\q. l\..-;".'/

ft) Draw arrows (-*----) to match R_and T to any one correct vertebra in Diagram b.1.Lukis anak pa-nah (-----) untuk memad,ankanR 6an T n"ora" ioio-ior* ,otuuertebrayang betul pada Raiah 5'L'[2 marksf[2 markahl

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(c) Explain one feature of thoracic vertebrae which is related to the mechanism ofrespiration , ,Teiangkan satu ciri uertebra toraks yatug berkaitan dengan mekan['srneresplrasl'

l3 marksll3 markah)(d) Explain the role of the vertebrae in Diagram 5.1 when movement of the body occurs'Tbrangkan peranan uertebra pada Raiai 5.1 semasapergerakan badan berlaku'

12marksl[2 markahl(e) Diagxam 5.3 shows a cross section of a normal bone tissue.Diagram b.4 shows a cross.section of the bone tissue of an individual suffering fromosteoporosis.

Rajah 5.3 menuniukkan satu keratan rentas bagi tisu tulang yang normal'Rajah 8.4 menunjukkan satu heratan rentas bagi tulang seoratug ndiuidu yang nxenghidap' ost'eoporosis.

Diagrnm 5.3Rojoh 5.3(i) State the condition of the bone in Diagram 5'4 as compared to the bone inDiagram 5.3.Nyatatan keadaantulang dalam Rajah 5.4 berbanding tulang pada Rajah 5'3'

ll marklIL markah]

Diag3am 5.4Roiah 6.4

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An individual suffering from osteoporosis is advised to drink plenty of milk. Explainwhy.Indiuidu yang menghidap osteoporosi's ,inasihatkan meminum banyak susu. Terangkanmengapa.

[2 marks][2 markah]Seetion BBahagian B[40 marks][40 rnarkah]

_ Answer any two questions from this section.Jawab nlana-nlano dua soaran d.aripad.a bahagian ini.Diagram 6'1 shows tissue P and cell Q. P is found in a multicellular organism. ..JQ is found in a unicellular organism.Raiah 6'l rnenuniukkan tisu P d'an sel Q. P terd,apat d,alam organisma multisel. e terd.apatdalam. organisma unisel.

Diagram 6.1Rajah 6.7

(ir)

Tissue PTlsu P Cell QSeI Q

Respiration equation' Persamaan respirasiGlucose+Oxygen.--+' .Capbondioxide + Water +'EnerryGluhosa+ Oksigen ->Karbon dioksida + Air + Tenaga

Respiration equationPersatnqan respirasiGlt:CoSe -+Carbondioxide + Ethandl + EnerryGlukosa _->Karbon dioksida + Etanol + Tenaga

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(a) Based ona. Diagram 6.1, explain the cellular respiration process that occurs in P and in[4 marks]Berd,asarkan Rajah 6.1, terangha,n.proses espirasi sel yang berlaku di P dan di q-[4 rytarkah]

(b) Diagram 6.2 shows two individuals, M and N, in two different situations. M is in avigorous activity while N is at rest.nijan G.2 rnenunjukkan d,ua indiuidu, M dan N, dalam dua situasi yang berbeza. Mseilang melakukan satu aktiviti cergas manakala N berada dalarn keadaan rehat.

Individu MIndiuidu M Diagram 6.2Rajah 6.2

Basedon Diagram6.2, explain the difference n the physiqlogicalprocess hat occurs norgans R, S and I for individual M and individual N. 16marhslBerd,asarkan Rajah 6.2, terangkan perbezaatu proses isiologi yang berlaku pada organ R,S d,an T basi ind,iuid.u M dan indiuidu N. [6 markah]

(c) A pond contains a lot of aquatic plants. Diagram 6.3 is a graph which shows the changesin the percentages of dissolved oxygen and dissolved iarbon dioxide in the pond over aperiod of 24 hours.Sebuah kolam mengand,ungi banyah turnbuhan akuatik. Rajg'h 6.3 ialah graf yangmenunjukkan perubahan peratusan kandungan oksigen terlarut .dan karbon dioksidaterlarut d,alam kolam itu bagi tempoh 24 iam.

Individu NIndiuidu N

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PercentagePeratusan

OxygenOksigenCarbon dioxideKarbon dinksida

fime/hourMasa/jatn

Basedon the.gralh il Diagram.6.3,explain the differencesn the percentagesof dissolvedxygenand dissolvedcarbon dioxiie ; ;h; ;;; during ,t"s" i,-rtage y and stageZ.[lO nlarks] rv'rq uurruS' DU'aEE ^' ' !Berdasarkangraf,padtaR3'iahp.-3, grangkanperb,ezaanerubahanperatusan kand,ungdnoksigen erlarut dan karbin d'ioksid,aelhrui d.alamkoiam itu ii peringkat x" peringkatY d'an peringkat z. 'wov"o t't"'t' tt' p [L0 markah]

Diagram 7'1 show-sln:'-"**:: of growth, X, y and z, at thetip of a plant shoot.zones L' 2' 3 and 4 show the ctanges that occur in the "uir" ao*ing the stages of thefowth. *r vrrv wvuD trL'rll

?:#:"::".menuniukhan peringkat-peringhatpertumbuhan, x, y, d,anz, pad.ahujung pucukt::r"';n^:ro#r|#.enuniukk'an perubahan vans diatami oleh ser-selsemasaperinskat

---- ' - t- , ,

0000 0600 1200 1800 2300Diagram 6.8Rajah 6.3

- - - - - ---"-

Zone LlZon LzoneiZ&.2Zone 3lZon BZone 4lZon 4

-__+ Y

Diagram Z.lRajah 7.L(a) Pasedon Diagram 2.1, explain the meaning of growth.BerdasarkanRajah 7.!, tiranghan maksud.pertumbuhan. [4 marks)

[4 markah]


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(b) (r) Auxin is a plant hormone which helps in plant growth.Diagram 7.2 shows the growth of a plant shoot towards light.Auksin ad.alah hormon tumbuhan yang membantu pertumbuhan tumbuhan.Rajah 7.2 menunjulzkan pertumbuhan pucuk tumbuhan ke arah cahaya.

Light raysSinaran cahaya

Diagran 7.2Rajah 7.2Explain the role of auxin'iir the growth of the plant shoot as in Diagtam7.2.[4 marhs]Terangkan perancrn auksin dalam pertumbuhan pucuk tumbuhan seperti padaRajah 7.2. 14 markahl

(ii) State two commercial values of auxin in agriculture.Nyatakan daa ni.lai komersil auksin dalam pertanian.

f2 marksl12markahl

(c) (t State three differences between primary growth and secondary growth. l3 m'arkslNyatahan tiga perbezaan antanrapertumbuhan primer d.an pertumbuhan sekund'er.

(ii) Explain the benefits to the plants that undergo secondarythose that do not undergo secondary growth'How does this affect their economic value?

[3 markahfgrowth as compared to

17markslTerangkan kebaikan tumbuhan yang mengalami pertumbuhan sekunder berbandingd,engan umbuhan yang tidak rnengalami pertumbuhan sekunder.Bagaimanakah keadann ini menjejaskan nilai ekonomi tuntbuhan tersebut?l7 markah)

The following organisms are found in a paddy field community.Organisma-organisma berikut terdapat.dalam satu komuniti sawah'padi.Grasshopper, Paddy plant, Caterpillar, Frog, Owl, Snake, RatBelalang, Pokok padi, Beluncas, Katak, Buru.ng hantu, Ulan Tlhus

These organisms interact with each other in the community.Organisina-organisma ini saling berinteraksi antara satu san"Laain dalam komunititersebut.

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(a) (i) Based on the above organisms, construct:Berdasarkan organisnxa-orgonisma d,i atas, bina:- A food web showing the iriteraction of ail organismsSatu jaringan maleanan yang menunjukkanl,ileraksi semua organisma- A pyramid of numbers consisting of four trophic leverssatu piramid nombor yang mengand,ungiempat aras trof

[4 marks)[4 markah)(ii) Grasshoppers and caterpillars are pests for paddy plants.How can the population of grasshopp"", urrd caterpillars be controlled?Explain the impact of the control methods on the paddy field community.

Belalang d'an beluncas nxerupakan perosak bagi pokok pad.i.Bagaimanakah populasi belalang d,an beluncis iapat d.ihaw:al?Terangha^, impak kaedah pengawalan itu ke atas komuniti sawah pad.i.

[6 marks]

[6 markah](b) A paddy field area is developed into an industrial area as shown in Diagram g.Kawasan sawahpadi dibangunkan menjad,ikawasanperind,ustrian sepertiyang d.itunjukkanpada Rajah B.

Diagram 8Rajah IDiscuss the good and the bad social, economicdevelopment.Bincangkan kesan baik dan kesan buruk sosial.pembangunan ini.

and environmental effects of thisILO markslekonomi dan persekitaran akibat

[L0 markah]

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I (a) Diagram 9.1 shows the processof colonisation and succession n a habitat.Rajah 9.I menunjuhkan prosespengkolonian dan penyesaran dalam suatu h'abitat.

Diagrarn 9.1Raiah 9.1What is meant by "colonisation and succession in a habitat"?Based on Diagram 9.1, explain how colonisation and successionbring about the formationof the primary forest in a habitat. ILO rnarkslApakah yang dimaksudkan dengan "pengkolonian dan penyesaran d,alam suatuhabitat'?Berdasarkan Rajah 9.L, teranghan bagaimana pengkolonian dan penyesaran membawahepadapembentukan hutan primer dalam suatu habitat.

(b) Diagram 9.2 shows an ecosystem n Malaysia.Rajah 9.2 menunjukkan suatu ekosistem di Malaysia.

lL} markahl

Diagram 9.2Rajah 9.2Based on Diagra m 9.2, discuss why the ecosystemhas to be maintained.Berdasarkan Rajah 9.2, bincangkan kenapa ekosistern ni perlu dikekalkan. [10

marks]

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Paper 2SectionA1- (a) (t SkinTbansporting oxygenRegulating body temperatureEliminating ureaConverting excess glucose to glycogenAs a protective layer

(b) X: Because skin consists of various types of tissuessuch as connective tissue; muscle tissue; combined. together to perform specific functions.Erector mriscle: Becauseerector muscle consists ofspecialised long cells called muscle fibres .(c) I lBlood circulatbry system

I lRespiratorysystemI Y llntugomentar5rsystemI Ylp*"""torysystem

(d) Erector muscle: Erector muscles in the skin relaxcausing the hair to }ie flat.Hair follicle: The hair follicle lies flat to increasethe heat loss through conduction and radiation.


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Sweat gland: The sweat gland is stimulated toproducesweat onto the surfaceofthe skin where itevaporatesand givesa coolingeffect o the body.

1. The liydrophilic heads of the outer layer ard incontact with the extr4cellular environment.2. The hydrophilic tails of the phospholipidmolecules form a selective barrier of theplasma membrane.Process n Diagram 2.1: Facilitated difrlsionProcess n Diagram 2.2: Active ransport(il Glucose molecules are lipid-insoluble andare too large to pass through the pores in the' plasma membrane. Carrier proteins in themembrane are able to carry'these moleculesacross the membrane via facilitated diffirsion.(ii) Calcium ions transported into' the cellby active transport tlat move moleculesagainst concentration gradient.

. - One site of the carrier protein binds the' calcium ions and another site binds theATPmolecule.- The ATP molecule is split into adenosinediphosphate (ADP), phosphate (P) andreleases energy to the carrier protein.- These energ'y changes the shape of thecarrier protein to release.the calcium ionsoutside the cell-

P : MetaphaseQ: ProphaseR : Anaphase1. The chromosomesbecome shorter and thicker.2. Each chromosome consiets of two sister

chromatids joined together at the centromers.3. Spindle fibres begin to form between thecentrioles.Stage P: The chromosomesare arranged randomlyat the cell e{uator called metaphaseplate.Stage R: The two sister chromatids of eachchromosomes are pulled apart to the oppositepoles.The use of tissue culture technique where planttissue are cut into small pieces ealled explants.Explants are transferred into a test tubecontaining a culture medium. Ttre explants dividethrough mitosis and develop new shoots. The rootswill then develop through mitosis producing youngplants.

NuclearmembraneNucleolus

Daughter cell 1P: PhosphateQ : Nitrogenous base

(t Chromosomhlmutation- deletion(ii) Environmental agents such ad radiation.(r) Female(ii) Disease:Down'ssyndromeReason: Has an extra copy of chromosomesnumber 21.Tbe allele for black fur is dominant. One of theparents has homozygous for black fur, therefore allof the offspring have black fur. (heterozygous)R : Cervical vertebraeT: Lumbar vertebrae

The twelve thoracic vertebrae articulate with thetwelve pairs of ribs. Movement of the rib cage rrebrought about by intercostal muscles between theribs.

(e)

2 (a)

3 (a)

(b)

4 (a)o)

(b)

(c)(d)

(c)(d)

(e)

5 (a)(b)

(c)

(d)

urrliSubstanceBohon ---_'u ' e\ a qffinMffifr lOutside the, I LuarselJInside the cellDalam sel

Daughter cell 2

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(d) Between the vertebrae are intervertebral discswhich permit various movements of the vertebralcolumn and absorb vertical shock.(e) (t The bone is thinner, more brittle and moreporous.(it Milk contain calcium, phosphorus andvitamin D which are neededfor the formationofbones.Section B6 (a) Aerobic respiration occurs in P because oxygenis present in this respiration and produce carbondioxide, water and energy.

Anaerobic respiration occurs in Q because oxygenis absent in this respiration and produce carbondioxide, ethanol and energY.(b)IndividualM IndividualN

R

S

T

The muscles requiremore oxygen and glucoseto release energy, thusthe breathing rateincreases and the lungsenlarge and expand withmore oxygen with eachbreath.The heart beats fastetso that oxygen can bebrought to the musclesat a frster rate. In ondento beat faeter, the heartmuscle also requiresmore oxygen,hence lrereis an increase in theamount of blood flow toit.Blood flow to the kidneyis reducedbecausemorewater is lost throughsweat. Therefore, lesswater is brought to thekidneys by the blood forexcretion.

The breathing rate atrest is normally 18 to 20breaths per minute, thelungs enlarge and expandduring inhalation andreturn to its original domeshape during exhalationregularly.The heartbeat rate isnormal, between 60 to 70beatsper minute.

Blood flow to the kidney ishigher becausemorewateris lost through urine.Therefore, mbre water isbrought to the kidneys bythe blood for excretion.

The green aquatic plants use carbon dioxideto undergo photosynthesis, while oxygengasesare released.At stageX, morning, the rate ofphotosynthesisis low because the light intensity and thetemperature is low. Hence, the percentage ofdissolved oxygen is low, while the percentageof carbon dioxide is high. At one point, therate of photosynthesis is equal to respiration'At stageX midday, the rate ofphotosynthesisis high because the light intensity and thetemperature is high. Hence, the percentage ofdissolved oxygen is high, while the percentageofcarbon dioxide is low.At stage Z, in t};re evening, the rate ofphotosynthesis is lower than respirationbecause the light intensity and the

temperature is low. Hence, the percentageofdissolvedoxygen s low, while the percentageofcarbon dioxide s high.Growth is an ineversible process whichinvolves a permanent increase n the numberof cells, size and volume of cells and cellsbecomespecialised.Zones 1 and 2 show the number of cells isincreasing.7,ote 3 shows the size of volume of cells isincreasing.Zone 4 shows the cells become specialised.Auxins show positive phototropism inplant shoots.When a plant is exposed o light from onedirection, auxins build up on the side inf,heshade.This causesthe cells on the shade regionelongate or lengthen more and fasterthan the cells on the brighter side.As a result, the shoot bending towards

the light.Stimulate the growth of adventitiousroots from the stem.Parthenocarpy - induce the developmentof fruit without fertilisation to produceseedlessruits.Primary growth is the growth of herbaceousplants that occuresafter germination.Secondary growth is the growth of woodyperennial plants like forest trees that occursafter primary growth is completed.During primary growth, a plant undergoescell .division, cell elongation and celldifferentiation.During secondary growth, a plant undergoesgrowth in the diameters of the stems, rootsand trunks.Primary growth begins when meristematiccells .at the apical meristems undergo rapidcell division.Secondary growth begir-rs when lateralmeristems. of both the stem and the rootundergo rapid cell division.

7 (a)

(b) (t

(c) (t

(ii)

(ii) - The plants that undergo secondarygrowth have long lifespans compared. to those that do not undergo secondarygrowth.'Secondary growth produces seconda4ixylem called wood. This woody partsthat are stiong and hard makes theplants suitable as beams for buildingsand various wodden fixtures such asfurniture.Secondary' Crowth Produces moresecondary phloem and secondary rylemwhich form the metlullary rays which is. an attractive feature in furniture likedining tables and decorative items.Some plants that undergo secondarygowth such.as merawan has a toughbark, produce useful resin and oils.

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(a) (r)Paddyplant

SnakeFrog

Grasshopper,caterpillar, ratPaddy plant

Apyramid of numbersThe population of grasshopper andcaterpillars can be controlled bybiological control method throughprey-predator interaction.Grasshopper and caterpillars are theprey, while frogs are the predator.When there are sufficient paddy plant innature, predators and preys control eachother's population. When the number ofpredators increases, he numbdr ofpreyswill decreasessince they are eaten by thepredators.Hence, the population of snake isincreases.Followed by the increasing of owlpopulation.On the other hand, the rat populationdecreases as a result of increasingpredation/snake population.

A paddy field area is developed into anindustrial area which known as urbanisation.The drive for development has led to socialactivities, economic activities and variousenvironmental problems,Good social effects:1. The population in this development areaincreases rapidly because of migration.This is because he factories increase jobopportunity.2. The factories can produce more foodsupplies to fulfill the need of humanpopulation.

Bad social effect:Extreme migration causes living spacedecreases,Good economic effects:1. More basic facilities such as hospitaland school are built for the better live ofhumau in this area.2. A lot of transportation system networkare built for the better live of human inthis area.3. New housing project are built to supportthe increment of human populationrapidly.

Bad economic effects:Demand for food and shelter increase, thereforeprices of food ncrease.Bad environmental effects:1. Sulphur dioxide from this factories combineswith rainwater to form acid rain.2. Oxides of nitrogen released by the factoriesdissolved in rainwater to form acid rain.Oxides ofnitrogen can causebronchitis.3. Carbon monoxide released by the factoriescombines with hemoglobin and affects thetransportation of orygen to body cells. Thiscauses atigue and headaches.4. Increase of domestic waste as well as sewagedischarge from houses causewater pollution.(a) Colonisation is a process where spores and seedsof certain plants start to germinate and growin newly formed areas where no life has existedpreviously.

Succession in a gradual process in which onecommunity changes the environment so that it isreplaced by another community.Succession in a disused pond begins with thegrowth of pioneer species such as phytoplankton,algae and submerged plants like Hydrilla. T'lnefibrous roots of these plants penetrate deep intothe soil to absorb nutrients and bind sand particlestogether.When the pioneer species die and decompose,moreorganic nutrients are released into the pond. Thehumus and soil which erode from the sides of thepond are deposited on the base of the pond, makingthe pond shallower. As a result, this conditionbecomes more suitable for floating plants such asduckweeds.These floating plants float freely on the surfaceof the water and receive sunlight directly. Thefloating plants can be reproduce. rapidly byvegetative propagation causing the submergedplants to die due to lack ofsunlightThe submerged plants remaining decomposedincrease more organic matter on the base of thepond. At the same time, more erosion occurs atthe edge which results in more sediments beingdeposited on the base of the pond. The pondbecomes shallower which makes it suitable foremergentplants suchas sedges.When these emergent plants die, their remainingdecomposedadd to ths ssdimsnts on the base ofthe pond which makes the pond shallower. Thecondition of the pond now beeomesmore favourable. for land plants like small herbaceous weeds suchas Euphorbia hirta.As time passes, the land becomes drier. Landplants such as shrubs, bushes and woody plantsbecomenumerous,A primary forest emerges and eventually turnsinta tropical rainforest.

Caterpillar--_\Grasshopper-->Fiog ----> Owl.r /Rat -----+ sf,^u./

Afood web

(ii)

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(b) _ Diagram 9.2 showsan ecosystemofrainforest.An ecosystem is a community of livingorganisms such as plant, monkey,deer, snail,butterfly interacting with one another anclwith the non-living environment such aswater and temperature.In this ecosystem, the green plants act asproducers which directly produee food for deerand the fruits for monkey as well.This ecosystemprovides the plants and theanimals with the basic resources of life suchas shelter, Iiving space,nesting and breedingsites. For example, a single tree can be ahabitat for birds and monkeys.Rainforest provide biodensity.Green plants undergo photosynthesis whichwater, light and carbon dioxide gases areneeded. During respiration process, animalreleases carbon dioxide gaseswhich is usedfor photosynthesisprocessby plants.Plants in tropical rainforest provide rawmaterials for mediciine such as treatment ofcancerandAIDS.At the same time, photosynthesis processproduces oxygen gases which is used byanimal during respiration process.This ecosystem has to be maintained toensure the snail has space/habitat to live.Otherwise the snail will loss their habitatcausing extinction of snail population.This ecosystem provide habitat for butterfly


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s?o Clalogg rrd fi2,

[60 marks]16OmarkahlAnswer all questions in this section.' Jawab sernua soalan dalam bahagian ini.

Diagram 1 shows a cross section of organ X in the human body.Rajah L merutnjukkan satu keratan rentas bagi organ X dalam badan manusia.

Sweat glandKelenjar peluh

Diagram 1Rajah L(a) (r) Name organ X.Namakan organ X.

*-rjT...{*\ - ;; i l l r r :1i i1r\klF-*il,;#

[l marh]fl markah](ii) Table 1 shows the function of several organs in the human body.Jadual L menunjukkan fungsi beberapaorgan dalam badan rnanusia.

Thansporting oxygenMengangkut oksigenRegulating body temperatureMengawal suhu badanEliminating ureaMenyinghirkan ureaConverting excess glucose to glycogenMenukar glukosa berlebihan kepada glikogenAs a protective layerSebagai apisan pelindung Table 1Jad.uol I :

spm 4551 2007 biology k2 berjawapan

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