SPM Biology 2007 k2

!.n to the three co*ect t#t1'o"'f"tft'" gmFl** n"ffiu in rable 1.sil Ih3

??d" (v) bggl tiga fungsi organ X ying b-etul, d.alam pitak-petak yang d,isediakandalam Jadual t.

[3 tnark][3 rnarkahl

(b) Erector muscle is a tissue.State reasons why X is classified as an organ and erector muscle is classified as atissue.

--- --o---

Otot regang ialah tisu.Nyatakan sebab nxengapa. X d'iketaskan sebagai organ d,an otot regang sebagai tbu.

X:

[2 marks]12 markahf

k) Jlre following information shows :o-ol" of the organ systems found in the human body.Maklurnat berikut menuniukkan beberapo orgoi yang terd,apat d.atam badan manusia.fick (rz) the two systems which contain org€rn X, in the boxes provided below.Tandn (/) basi d'ua sistem yang mengand.uogi orgonX" d.alam peiak-petak yang d,ised,iakandi bawah.

| | Blood circulation system/Sjs tem pered,aran d,arah

Respiratory systenr/Si stem respirasi

Integumentary syste ml Sistem integum,en

Excretory system/Sls tem perku,muhan

Itln

Erector muscle I 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.Tbranghctn peranan otot regang, bulu rorna d,an kelenjar peluh d.alam mengekalkan suhubadan pada hari yang pa,nos. : ' -----:

193

Erector muscle I Otot regang:

Hair follicle I Bulu ron'La:

Sweat gland I Kelenjar peluh:

tB marksl[3 markahl

Diagram 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

194

m,erentasi membran plasnt a.

Substancelc Bahan -----\" uo !

-ttg

SubstanceBahon -----

?".r""1 "tf":@'

@oI'1"" Outside the cell'Luar sel

o o0a

ofATi O

(a) In Diagram 2.1, label the following structures:Pada Rajah 2.1, Iabel struktur-struktur berikut:

Phospholipid bilayer, with letter JDwilapisan fosfolipid., dengan huruf JCarrier protein, with letter KProtein pernbawa, d,engan huruf K

[2 rnarks]12 markahl

(b) state two characteristics of the phospholipid bilayer.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 proses pergerakan bahan merentasi membran plasma yang d,itunjukkan padaRajah 2.I dan Rajah 2.2.

Process in Diagra m 2.L I proses pad,a Rajah 2.I

Process in Diagram,2.Z I proses pad,a Rajah 2.2

1.

2"

(c)

[2 marksl12 rnarkahl

(d) (t Glucose molecules are transpo"tq airos: the plasma membrane into the cell throughthe proces"_"!oytt in Diagram 2.L. Explain *fryMolekul-molekul glukosa ilianghut ke iet merentasi membian plasma melalui prosesydng ditunjukkan pad,a Rbjoh 2.L. Terangh:a,n tnengapa.

,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,Iam sel.

195

[4, marksl14 rnarkahj

Diagram 3.1 shows three stages of 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.L

Name the stages R Q and R in the spaces provided in Diagram 3.1.Namakan peringkat 4 Q dan R datarn rucrng ydng disediakan dalam Raiah 3-L.

tB marksl13 marhahl

Explain what happens at stage Q.Teranghan apa ycnl,g berlaku 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>r

t..a- r' ((,D

StageF' lPer inghatR

[2 marks]12 ma,rkahJ

196

(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, it is found that chromosome Mrs not separated.Rajah 3'2 rnbnunjukkan suatu sel pad,a peringhat P. Pad,a peringhat seterusnya, d.id.apatikromosom M tidak berpisah.

Chromosome MKromosornM

Diagrarn 3.2Rajah 3.2

-Complete the diagrams for the two daughter cells which will be formed in the space providedI IDelow.

Lenghapkan raiah kedua-d'ua sel anak yang akan terbentuk pad,a ruang yang d.ised.iaitznn dibawah.

Daughter cell 1 | Sel anak 1 Daughter cell2 | Sel,anah 2

12 marksl[2 marlnhl

197

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

Pentose sugarGuIa Pentosa

Diagram 4.1Rajah 4.1

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

Pi

a:

(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

12 marksl12 markahl

[3 marks]13 markahl

1.98

(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'kit7 gen-gen yang terd.apat pad.a suatu kromosom.Selepas suatu rawatan tertentu, gen'A didapati hilang.

(t


{"*" the process that has taken place on the chromosome.Narnakan proses yang terah berraiu pada,n o*ito* ili.-

-

B

c

d

E

IL mark]IL markahl

(ii) Name one factor that causes the process in a(cXi).Narnakan satra fahtor yang menyebabkoo pror"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 ffi678910r i : . :

f t i l00 lI ilf rr13

It19

1514 16 77 18

rI20

l l r2L


199

IT22

trxx

(r) Determine the sex of the individual.Terutukan iantina 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]12 markahl

(e) Diagram 4.5 shows the cross breeding between two mice.

Rajih 4.5 meinuniukkan kacuk silang antara dua eko,r tikus.

Homozygous black furHomozigot berbulu hitam

Homozygous white furHornozigot berbulu putih

OffspringAnak

Black furBerbuluhitam

Black furBerbulu hitarn

Diagram 4.5Raioh 4.5

Black furBerbulu hitam

Black furBerbulu hitam

Explain why atl of the o{fripring have black fur.Tbrangkan tnengcrpa senl,ua anak tikus itu berbulu hitam.

[2 marks][2 marhah]

5 Diagram 5'1 shows the human vertebral column. Diagram b.2 shows the two types of vertebrae,R and T in the human vertebral column.Raiah 5'1 menunjukkan turus uertebra maruusia. Raiah 8.2 menunjukkan d,ua jenis uertebraR dan T, dalam turus uertebra manusia.

Diagram 5.1Rojah 5.L

(a) Name the vertebrae.Narnakan uerteb ra-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,ankan R 6an T n"ora" ioio-ior* ,otuuertebra yang betul pada Raiah 5'L'

[2 marksf[2 markahl

201,

(c) Explain one feature of thoracic vertebrae which is related to the mechanism of

respiration , ,Teiangkan satu ciri uertebra toraks yatug berkaitan dengan mekan['srne resplrasl'

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 semasa pergerakan badan berlaku'

12 marksl[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 from

osteoporosis.

Rajah 5.3 menuniukkan satu keratan rentas bagi tisu tulang yang normal'

Rajah 8.4 menunjukkan satu heratan rentas bagi tulang seoratug indiuidu 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 in

Diagram 5.3.Nyatatan keadaan tulang dalam Rajah 5.4 berbanding tulang pada Rajah 5'3'

ll marklIL markah]

Diag3am 5.4Roiah 6.4

202

An individual suffering from osteoporosis is advised to drink plenty of milk. Explainwhy.Indiuidu yang menghidap osteoporosi's d,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.


(ir)

Tissue PTlsu P

Cell QSeI Q

Respiration equation' Persamaan respirasi

Glucose+Oxygen.--+ ' .Capbon dioxide + Water +'Enerry

Gluhosa + Oksigen .->Karbon dioksida + Air + Tenaga

Respiration equationPersatnqan respirasi

Glt:CoSe -+Carbon dioxide + Ethandl + Enerry

Glukosa _->Karbon dioksida + Etanol + Tenaga

203

(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 respirasi 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 a

vigorous activity while N is at rest.nijan G.2 rnenunjukkan d,ua indiuidu, M dan N, dalam dua situasi yang berbeza. M

seilang melakukan satu aktiviti cergas manakala N berada dalarn keadaan rehat.

Individu MIndiuidu M


Based on Diagram6.2, explain the difference in the physiqlogical process that occurs inorgans R, S and I for individual M and individual N. 16 marhsl

Berd,asarkan Rajah 6.2, terangkan perbezaatu proses fisiologi 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 changes

in the percentages of dissolved oxygen and dissolved iarbon dioxide in the pond over a

period of 24 hours.

Sebuah kolam mengand,ungi banyah turnbuhan akuatik. Rajg'h 6.3 ialah graf yang

menunjukkan perubahan peratusan kandungan oksigen terlarut .dan karbon dioksida

terlarut d,alam kolam itu bagi tempoh 24 iam.

Individu NIndiuidu N

204

PercentagePeratusan

OxygenOksigen

Carbon dioxideKarbon dinksida

fime/hourMasa/jatn

Based on the.gralh il Diagram.6.3, explain the differences in the percentages of dissolvedoxygen and dissolved carbon dioxiie ; ;h; ;;; during ,t"s" i,-rtage y and stage Z.[lO nlarks] rv'rq uurruS' DU'aEE

^'' !

Berdasarkan graf,padta R3'iah p.-3, tgrangkan perb,ezaan perubahan peratusan kand,ungdnoksigen terlarut dan karbin d'ioksid,a telhrui d.alam koiam itu ii peringkat x" peringkatY d'an peringkat z. 'wov"o t't"'t' (tt' p

[L0 markah]

Diagram 7'1 show-s ln:'-"**::

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 thegfowth. *r vrrv wvuD trL'rll

?:#:"::".menuniukhan peringkat-peringhat pertumbuhan, x, y, d,an z, pad.a hujung pucuk

t::r"';n^:ro#r|#.enuniukk'an perubahan vans diatami oleh ser-sel semasa perinskat

- - - - ' - t - , ,

0000 0600 1200 1800 2300


- - - - - -

- -"-

Zone LlZon Lzone ziZ&.2Zone 3lZon B

Zone 4lZon 4

-

__+ Y

Diagram Z.lRajah 7.L

(a) Pased on Diagram 2.1, explain the meaning of growth.Berdasarkan Rajah 7.!, tiranghan maksud. pertumbuhan. [4 marks)

[4 markah]

(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 7.2

Explain 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 pada

Rajah 7.2. 14 markahl

(ii) State two commercial values of auxin in agriculture.

Nyatakan daa ni.lai komersil auksin dalam pertanian.

f2 marksl

12 markahl

(c) (t State three differences between primary growth and secondary growth. l3 m'arksl

Nyatahan tiga perbezaan antanra pertumbuhan 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 markahf

growth as compared to

17 marksl

Terangkan kebaikan tumbuhan yang mengalami pertumbuhan sekunder berbanding

d,engan tumbuhan 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"La lain dalam komuniti

tersebut.

206

(a) (i) Based on the above organisms, construct:Berdasarkan organisnxa-orgonisma d,i atas, bina:- A food web showing the iriteraction of ail organisms

Satu jaringan maleanan yang menunjukkanl,ileraksi semua organisma- A pyramid of numbers consisting of four trophic levers

satu piramid nombor yang mengand,ungi empat 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 I

Discuss the good and the bad social, economicdevelopment.Bincangkan kesan baik dan kesan buruk sosial.pembangunan ini.

and environmental effects of thisILO marksl

ekonomi dan persekitaran akibat[L0 markah]

207

I (a) Diagram 9.1 shows the process of colonisation and succession in a habitat.Rajah 9.I menunjuhkan proses pengkolonian dan penyesaran dalam suatu h'abitat.

Diagrarn 9.1Raiah 9.1

What is meant by "colonisation and succession in a habitat"?Based on Diagram 9.1, explain how colonisation and succession bring about the formationof the primary forest in a habitat. ILO rnarksl

Apakah yang dimaksudkan dengan "pengkolonian dan penyesaran d,alam suatuhabitat'?Berdasarkan Rajah 9.L, teranghan bagaimana pengkolonian dan penyesaran membawahepada pembentukan hutan primer dalam suatu habitat.

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

lL} markahl


Based on Diagra m 9.2, discuss why the ecosystem has to be maintained.

Berdasarkan Rajah 9.2, bincangkan kenapa ekosistern ini perlu dikekalkan.

[10 marks]

llD markahl

208

r-,d

Paper 2SectionA1- (a) (t Skin

Tbansporting oxygen

Regulating body temperature

Eliminating urea

Converting excess glucose to glycogen

As 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: Because erector muscle consists ofspecialised long cells called muscle fibres .

(c) I lBlood circulatbry system

I lRespiratorysystem

I Y llntugomentar5rsystem

I 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.

Sweat gland: The sweat gland is stimulated toproduce sweat onto the surface ofthe skin where itevaporates and gives a cooling effect to 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 in Diagram 2.1: Facilitated difrlsionProcess in Diagram 2.2: Active transport(il Glucose molecules are lipid-insoluble and

are too large to pass through the pores in the' plasma membrane. Carrier proteins in the

membrane 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 the

ATPmolecule.- The ATP molecule is split into adenosine

diphosphate (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 chromosomes become shorter and thicker.2. Each chromosome consiets of two sister

chromatids joined together at the centromers.3. Spindle fibres begin to form between the

centrioles.Stage P: The chromosomes are arranged randomlyat the cell e{uator called metaphase plate.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.

Nuclearmembrane

Nucleolus

Daughter cell 1

P: PhosphateQ : Nitrogenous base

(t Chromosomhl mutation- deletion(ii) Environmental agents such ad radiation.(r) Female(ii) Disease: Down's syndrome

Reason: 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)

urrliSubstance

Bohon ---_'u ' e\ a q

ffinMffifrlOutside the

, I Luarsel

JInside the cell

Dalam sel

Daughter cell 2

230

(c)

(d) Between the vertebrae are intervertebral discs

which permit various movements of the vertebral

column and absorb vertical shock.(e) (t The bone is thinner, more brittle and more

porous.(it Milk contain calcium, phosphorus and

vitamin D which are needed for the formationofbones.

Section B6 (a) Aerobic respiration occurs in P because oxygen

is present in this respiration and produce carbon

dioxide, water and energy.

Anaerobic respiration occurs in Q because oxygen

is absent in this respiration and produce carbon

dioxide, 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 tlrereis an increase in theamount of blood flow toit.

Blood flow to the kidneyis reduced because morewater 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 70beats per minute.

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

The green aquatic plants use carbon dioxideto undergo photosynthesis, while oxygengases are released.At stage X, 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 percentage ofdissolved oxygen is low, while the percentageofcarbon dioxide is high.

Growth is an ineversible process whichinvolves a permanent increase in the numberof cells, size and volume of cells and cellsbecome specialised.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 to light from onedirection, auxins build up on the side inf,he shade.This causes the cells on the shade regionelongate or lengthen more and fasterthan the cells on the brighter side.As a result, the shoot bending towardsthe light.Stimulate the growth of adventitiousroots from the stem.Parthenocarpy - induce the developmentof fruit without fertilisation to produceseedless fruits.

Primary growth is the growth of herbaceousplants that occures after 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 parts

that 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.

23L

(a) (r)

Paddyplant

Snake

Frog

Grasshopper,caterpillar, rat

Paddy plant

Apyramid of numbers

The 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, the numbdr ofpreyswill decreases since 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 area

increases rapidly because of migration.This is because the 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 hospital

and 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 increase.Bad environmental effects:1. Sulphur dioxide from this factories combines

with rainwater to form acid rain.2. Oxides of nitrogen released by the factories

dissolved in rainwater to form acid rain.Oxides ofnitrogen can cause bronchitis.

3. Carbon monoxide released by the factoriescombines with hemoglobin and affects thetransportation of orygen to body cells. Thiscauses fatigue and headaches.

4. Increase of domestic waste as well as sewagedischarge from houses cause water 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 ofsunlight

The 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 foremergent plants such as sedges.

When these emergent plants die, their remainingdecomposed add to ths ssdimsnts on the base ofthe pond which makes the pond shallower. Thecondition of the pond now beeomes more 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 plantsbecome numerous,

A primary forest emerges and eventually turnsinta tropical rainforest.

Caterpillar--_

\Grasshopper-->Fiog ----> Owl.

r /Rat -----+ sf,^u./

Afood web

(ii)

232

(b) _

Diagram 9.2 shows an ecosystem ofrainforest.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 ecosystem provides 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 gases which is usedfor photosynthesis process by plants.Plants in tropical rainforest provide rawmaterials for mediciine such as treatment ofcancer andAIDS.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 butterflyto ensure the population of butterflymaintained.Timber, rubber and organic oils playimportant role in the country's economies.Nitrogen cycle, pollination and regulation ofatmosphere temperature are provided due tothe diversity in plants and animals.

s?o Clalogg rrd fi2,

[60 marks]16O markahl

Answer 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 i

1r

\klF-*il,;#

[l marh]fl markah]

(ii) Table 1 shows the function of several organs in the human body.Jadual L menunjukkan fungsi beberapa organ dalam badan rnanusia.

Thansporting oxygenMengangkut oksigen

Regulating body temperatureMengawal suhu badan

Eliminating ureaMenyinghirkan urea

Converting excess glucose to glycogenMenukar glukosa berlebihan kepada glikogen

As a protective layerSebagai lapisan pelindung

Table 1Jad.uol I

192

:

--l

Documents

SPM Biology 2007 k2