f-

G/_i.Lj i. t i{*r i:riritvl t.d i*. i:ri,,.,i i. j.

GAUTENG DEPARTMENT OF EDUCATIONPREPARATORY EXAMINATION

2015

10832LIFE SCIENCES

SECOND PAPER

MARKS:TIME:

Pages 19

15021/2 hours

1083E

| ffiilliltililtriltiltil ilillt tiltil10832E

x@5

ilItililtilililtililil2

p.i.u.

GAUTENG DEPARTMENT OF EDUCATION

PREPARATORY EXAMINATION

LIFE SCIENCES(Second PaPer)

\TIME: 27, hours

MARKS: 150

INSTRUCTIONS AND INFORMATION

Read the following instructions carefully before answering the questions.

i i-irr screNces | , i'lisecold Paoei) 1083zr5 ! :

P.'i.n.

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

Answer ALL the questions.

Write ALL the answers in the ANSWER BOOK.

Start the answers to EACH question at the top of a NEW page.

Number the answers correclly according to the numbering system used in thisquestion paper.

Present your answers according to the instructions of each question.

l\ilake ALL drawings in penciland labelthem in blue or black jnk.

Draw diagrams, flow charts or tables only when asked to do so.

The diagrams in this question paper are NOT necessarily drawn to scale.

Do NOT use graph paper.

You must use a non-programmable calculator, protractor and a compasswhere necessary.

Write neatly and legibly.

LIFE SCIENCES(Second Paper)

SECTION A

AUESTION 1

1.1 Various options are given as possible answers to the following quesuons.Choose the answer and wriie only the letter (A io D) next io i-he questionnumber (1.1.1 to 1.1.10) in the ANSWER BOOK, for exampte 1. j.1 1 D.

1.1.1 The only ditference between the DNA of one member of a speciesand that of anoiher member of the same species is the ...

A order in which the bases occur in their chromosomes.B type of bonds present between the bases.C number of strands that make up the DNA.D positioning of ihe phosphate and sugar portion in the DNA.

1 .1.2 lf 20% ol the bases in a molecule ol DNA are cvtosine, what is iheratio of guanine to thymine in the same molecule?

1.1.3 The otfspring, ol a pure breeding brown horse that had been crossedwith a pure breeding white mare (female horse), were interbred. Brownis dominant. The expected percentage offspring will be ...

A 507. brown and 50% white.B 100% brown.C 25% brown and 75% white.D 75% brown and 25% white.

A 1:1B 3:1C 3:3D 2:3

P.T,O

1, 1.4 Tq. i t-. :,r, F6tr '/, 16^.ecp.rc ' ^h ,Se in mc ios (

(i),(ii) and (iii)(ii),(iii) and (iv)(i) and (ii) only(i),(ii) and (iv)

LIFE SCIENCES(Second Pape;)

1.1.5 The natural shape oi a DNA molecule is

A a single coiled strand.B a double helix.C the same as that of IRNA.D the same as that ol mRNA.

The following are evenis that take place in meiosis.

(i) Chromosomes are in meiaphase l.(ii) Crossing over has taken place.(iii) Chromosomes are ln the metaphase ll stage.(iv) Chromosomes are arranged in homologous pairs.

Which of the statements is TRUE regarding the diagramabove?

BcD

BcD

fnrh{

In DNA, ifstrand, the

the sequence of bases is AGG TTA CCG oncorresponding bases o'r the oher slrand are ..

GGA TTC,ccc ccT.AAT GGC.GGT CCT.

the one

ACC

TCCCTT

m

{xl

_10.00

ilxtflf

LIFE SCIENCES(Seeonit Paper)

1.1.7'oE:':ilt .-__:t

A teniative explanalion ior an observaiion is known as a...

A hypothesis.B theory.C law.D iact.

DaMin made most of his observations about evolution on the ...

A lslands oi Hawaii.B Indonesian lslands.C Galapagos lslands.D Phi Phi lslands.

Homologous chromosomes are described as ...

A being similar in structure and coding for the samecharacteristics.B a product ol the division of chromosomes.C identical daughter chromatids {ormed through DNA replication.D two chromosomes that code Jor different characterisiics.

Four difterent phenotypes are possible in the F1-generation if theparents' blood groups are ...

A BandB.B Aand B.C O and AB.D AB and AB. (10 x 2) (20)

1.1,8

1.1.9

'| .'l .10

P,T.O.

LIFE SCIENCES(Second Paperi

1.2 Give iheonly theBOOK.

1.2.1

1 .2.2

1 .2.3

1 .2.4

correct biological term for each of lhe lollowing descripiions. Writeterm next to the question nLrmber (1 .2.1 io 1 .2.8) in the ANSWFR

The representaiion oi ihe DNA oi a person as a series of light ancidark bands

A section of a DNA molecule that codes for a specitic characteristic

The change of the genetic material of an organism by humans toget desired changes

The explanation that species experience long periods withoutphysical change, iollowed by short perlods of rapid physicalchange

The phase of meiosis during which homologous chromosomesseparate and start moving towards opposite poles

The defect in cell division ihat leads to Down's syndrome

The structure that is made up of two chromatids joined by acentromere

A group of organisms that have similar characteristics that caninterbreed to produce fertile offspring

1.2.5

1.2.6

1 .2.7

1 .2.4

(8)

P.l.c.

LIFE SCIENCES(Second Paper)

'L3 lndicaie whether each of the statements jn COLUN/N I applies to A ONLY,B ONLY, BOTH A AND B or NONE of the items in COLUNi1N . Write A onry,B only, both A and B, or none next io the question number (1.3.1 to i.3.6) inihe ANSWER BOOK,

COLUMN I COLUMN II1.3.1 Discovered the shape of the

DNA moleculeFrancis CrickJames WatsonB

1.3.2 Evidence for evolution BiogeographyGeneticsB:

1.3.3 Darwin'sobservations A: Variations in a populationB: Production of more ofispring thanis required

1.3.4 An example of a reproductivejsolating mechanism

A: Species-specificcourtshipbehaviourB: Infertile offsprinq

1.3.5 Fossil site/s in Africa SterkfonteinGreat Rift VallevB

1.3.6 A type of cell division thatoccurs for the production ofgametes

MeiosisMitosisB

(6 x 2) (121

F.T,O

LIFE SCIENCES(Second Papet

1n A1 nvesliqai:on was co.ducled over a period oi 32 weeks lo tesi lhypothesis ihai mosquitoes develop resistance to DDT. The results oi iheinvestigaiion are given below. Study the graph below and answer thequestrons.

1.4.1

1 .4.2

At which period of time did the mosquitoes begin to developresistance towards DDT after spraying took place?

What was the approximate number of mosquitoes thai were non-resistant to DDT at the initial time of spraying? (Show all working)

How long did it take for the mosquiio population to reach itsmaximum number?

\2)

12)

(t )ts1

Number of mosquitoes that survived after DDT was sprayed

o

G

!,

E

o-o

z

1 1000

10000

90008000700060005000400030002000

10000 a 12 16 20 24 2A 32

Time (weeks) DDT was sprayed

p.T.o

1.5 Read the passage below about the 'Out of Africa,, hvpothesis.

LIFE SCIENCES I .-^^^^,,- I J(Second Paper) 10832/15

(1)

suPPort the 'Out

Which continent is believed to be the 'motherland' of the HomosPecies?

Name TWO types oi evidence that can be used toof Africa' hypothesis.

Name the oldest hominid that was found in Africa?

TOTAL SECTION A:

1.5.1

1.5.3

(2)

(2tt5I50

Origin ot modern humansThe 'Out-oi-Africa' hypothesis proposes that modern humans oriqinatedonly in Africa; then they migrated and supplanted populations ol Homoin Asia and Europe about 1 000 O0O years ago.

Adapted fromi , 6'" edition, p.359

P.T.G.

LIFE SCIENCES(Second Papei) 1AA3A15

SECTION B

QUESTION 2

2.1 The following diagram shows an important process that occurs during celldivision.

PROCESS IN CELL CYCLE

Diagram A

T

2.1.1

2.1.2

2.1.3

Name the process ihat is being represented in the diagram above.

During which phase in the cell cycle does the process mentioned inQUESTION 2.1.1 occur?

Describe the process that is illustrated in diagram A.

(1)

(3)(5)

(1)

P.i.ai.

LIFE SCIENCES(Secoirei Faper.i -i0632115

2.2 Humans show variations in characteristics such as Jingerprints. Humans havefive rnain types of iingerprints as shown in the diaqram below.

Tented arch Plain arch LooD Double looo Plain whorl

Learners carr'ed out an investigatjon based on the following hypothesis thatthey formulatedi

"Most learners have the plain arch-type of fingerp nt."

2.2.1 State TWO planning sieps that must be considered by the learnersbefore the investigation.

2.2.2 Explain ONE precaution that the learners must take to ensure theresults are valid.

2.2.3 List TWO ways in which the reliability of the investigation could betmproved.

2.2.4 The results of the investigation are shown in the table below.

(2)

(2)

12)

Main types ol finqerprints Number of learnersDouble loop 60LOOp 126Tented arch 115Plain arch 120Plain whorl

ldentify the independent variable in this investigation.

ldentify the dependent variable in this investigation.

Explain whether the learners' hypothesis will be acceptedrejected in ierms of the results recorded in the table.

(a)

(b)

(c) or

(1)

(1)

(10)

2.3

LIFE SCIENCES(Seconcl Paper)

Two paleoanthropologists used the same fossil daia to draw a model of ahominid evoluiionary tree. The two models they produced are shown below.Study the models and answer ihe questions that follow.

Adaoted liom Advanced Bioloav. M Kent,2OOO

Name the common ancestor to all hominids in both models. (1)

j.

2.3.1

2.3.2

2.3.3

2.3.4

2.3.5

How many million years ago did Homo erectus firsteanh in both models?

and Homo habilis in boih models.

State ONE reason why Homo ergasterjn Model 1 willas a'transiiional fossil'.

appear on(l )

Tabulate TWO diiferences regarding the evolution of Homo erectus(5)

be regarded(1)

Name TWO fossils found in South Africa that had characteristicsoI Ihe Austratopithecus afticanus. 12)

(10)

icz32/i z

PHYLOGENETIC TREES SHOWING HUMAN EVOLUTION

at!@ ts :

i rtoao r

J nlillion ? Nill'on

:.i.c

2.4 In 1997, scieniists irom the Foslin lnstitute in Scotiand claimed that they had clonecja lamb from a cell taken from the mammary glancj of a sheep. The lamb was ca eci'Dolly'and she became famous as she was the first mammal formed frorn a non_reproductive cell.

lhe diagram illustration below summarjses the process the scientists used.

{ ., I Dolly's

u/ru

cLoNllrlc oF A $HEEP

molher

ll,4ammary.gland cellremoved ;=r,.1

L::i,,1 A\ali,

Egg iionr another sheep

^'1til-, .) sCytoplasrnYNucleus exllacted andkeDt , disQarded,1+: it,qt

Cell discaddd NLI-cleus extractedt",---=rt \l].:;:lulJ

NucleLr\nsfited Into cell

@'renrriset esgI

Mitosis and de!€lopment of embryoinslde sufiogatf ftother produced ._.

r:al-ffi oottv. ttre tamu

2.4.2

2.4.3

2.4.4

ls Cell A formed by mitosis or meiosis? Give a reason lor youranswer.

Give ONE reason why the nucleus from the egg cell of ianoihersheep'was discarded.

Explain why the words 'fertilised egg' has inverted commas.

Give ONE reason why some people may object to clonjng.

(2)

(1)

(1)

(1)(5)

LIFE SCIENCES(Second Pape4 'lg83zi5

P.I,G.

2.5 In a certain type of parrois it was found that red eye coiour (R) ts dominantoygl blq."l eye cotour (r), while grey iajt feathers (c) were clomrnant overwhite tail feathers (g).A parrot breeder crosses a lemale homozygous ior red eyes and grey tailfeathers with a male homozygous tor black eyis and white t;il feathers.

2.5.1 Name the genotype of the:

(a) Female parrol

(b) t\tate parrot

2.5.2 Write down the genotypes of the gametes of the female.

2.5.3 cive the phenotype of an offspring having the genotype:

(1)

(1)

(2J

(1)

(1)(6)

2.6

(a) rrcg

(b) RrGg

Distinguish between:

2,6.1 Continuous and

2.6.2 Discontinuousvariation(2)

12)(4)[40]

LIFE SCIENCi€(Second Paper)

A{JESTION 3

lLlt-tssUltNUES i .,.| ,^ : :a(second Paper) ._ ____j-111:i _._--_,_.

Use the diagrams above to explain how Darwin would account forthe long trunks of elephants.

State the TWO Laws ol Lamarck.

Le* of !,{cc clht & i9{-lEethhe' ita^ 'e

31 The foliowing diagram illustrates ihe evoluiiofary process of selection ior longtrunks in eiephants. The mosi notable feature of all elephants is a long trunlor proboscis, used for many purposes, particularly breaihing, lifting water andgrasping objects.

1ffiffiffim -#hk'lfirffi

A

,'V.CrW=F/ Ad\Ul{ Gffifti$/ ffie

3.1 .1

3.1.2

(6)

(2J(8)

l,-;;-,;;-^-- -ll.trE>rJtEtlu:u i ."l(Second Pape4 ,.,,=31,, jj_: ,

,

3.2 Hurnans are classified as pfimaies, a group whjch includes chimpanzees.Although there are differences between hLtmans and oiher living pnmales, weatso snare many characterisiics with them, suggesting a common ancestor.

Study the diagrams below showing the peJvis of pan trogtodrte (cnmpanzee)and Hamo sapiens and answer the quesijons that foliow.

Pan troglodyte Homo sapiens

Pelvis of Pan troglodyte and Homo sapiens

3.2.1

3.2.2

3.2.3

State what is meant by the terrn bipedalism.

Explain TWO advantages of bipedatjsm.

Provide TWO reasons why the pelvis of Homo saplens is betteradapted for bipedalism compared to chimpanzees.

(2)

\4)

\41(10)

P.T,i3

I iLne scii,'rcEi -'_ I ,.J(Secoid Pape4 100ji/-i: i-_.-,_i

sEcTtoN c

QUESTION 4

Describe ihe process by which proteins are produced in ihe celis oi the human bodyand explain how gene mutations lead to altered characteristics resulting inhaemophilia, albinism and colourblindness.

Content: (17)Synthesis: (3)

NOTE: NO marks will be awarded {or answers in the form of flow charts, diagramsor tables.

TOTAL SECTION C: 20GRAND TOTAL: 150

FND