1984 Biology Paper I Marking Scheme

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"

" ,1'/'

_ " " \

i~~) (a ) ,

(11)

(iii)

(iv)

,tooth /premolar / molar

-2-

..-~" " . ,

to break food into small

••••• !•••••••••••••••••••••••••••

, "'1 ,,:.,' , ,./

pieces ~ J • • •• • •• • • • ••

easier to swallow

increase surface area for enzyme action, •••••••••••••••••• 1

. . ' " .(X

Sdrawing:i_ [ 5 5 CizCUe·a / C~c1a'r'' t 'y '• •• •• • • •• •• •• •• •• •• •• •• • • • • • •

zr: .' ••••••••••••••••••••••••••••-*labels enamel

dentine

pulp cavity.(; row n

root

cement

1

1

1

any FOUR ( '1 each) ...... ,. . 2

child .....................................................presence of permanent teeth below milk teeth •••••••••••••

'1.,' ....

10



(1)

(ii)

-3-

cut end"

X Z

,yct 1 tV- , c:--v

LAR GE smalleroj lume~"'h '. ' " ' h -tJ "" -

walt\ rVthinner THICK

.............. 1

.............. 1

* X - vein I v en ul e ( NO T v en a c av a) .'• •• •• •• •• •• •• •• ••• •• •

z _"y ~X

> < ~ ~..-t ~ Z ~tec{Z -7 X •••• • •• • •• • •• • •• • •• • •• • •• • •• • •• 1

* Z - artery I a rt e~ io .l e ( NO T aorta) ••••• '.......••••••••• ~

(iii) presence of valve in X and not Z . ~ .. . .. . .. . .. . .. . .. . .. . . 1

to prevent backtTard flow of blood •••••••••••••••• '••••••• ' 1

O R

feature importance

i nc re as e su rf ac e to promote filtration Iarea I increase for more efficient

branching cross-sectional diffusionarea w: !.thsurrounding ce1 1s

slow down blood flow from Z to Xbore,

diminished decrease blood pressure

thin-walled easier for diffusion /ultra-filtration

any T W O

Iairs

1 + 1\

1 + 1

(iv)

(v)

(vi)I

(vii)

* M

' * N

blood / plasma ... ' .lYmph I.tissue fluid / extracellular fluid /intercellular fluid / interstitial fluid ••••••••••

R.B.C. r w . ~ ' ) " ,?l\.o ,lAv-i. "

plasma' protein any TWO ••••••.••••••• ~ ••••••••••••••

blood platelets ,

1, 1

13

,__-- _-------'-",,-----r-------··--'--- ----'-----'-~-'.~'."



.~. . ' •". . .;---.,.---~. . . . . . '-'-~'.> •

"-"2. (b) (i)

(li)

Y 4 P c , - \

. (1) herbaceous stem - bends dovnea r ds •••••••••••••••••••

woody stem - remains straigh~ I unchanged ••••••••••••

. ' ' f

'.

'HI ,. •••• '" !'r!'". ,,,,I •.~,,!.~.t "'. ' t' . 0 ~ ...... .. ' t. ,. i·......'\. .", "

.__:...------_._--"".------

-4-

1

1

(2) both stems - remain straight /unchanged.............. 1

because s al t s ol ut io n cell sap

concentration high.hI, --A W

,hl'lA"" : " , . " . : ; :;\ . A (

nosmotic

lower higherpotential/a·r,

water .potential

Lowe r higher

( os mo ti c p re ss ur e

any O N E

1

low NOT acc~ptable)igh

water moves out of cells by osmosis ••••••.•.•.•••••••••.• 1cells become plasmolysed / flaccid I decrease in turgor.. 1

(iii) (1) herbaceous stems - mainly by turgidity of cells .•••• 1

.. (2) woody stems - m ainly suppo rtcd by thick-walled cells Ixy le~~ ••......••..•....•.•.•....••• -::-:. 1

8

.·"i



...".~ 0 .", _ ".. ._ ~ ._ ." ~ - "-"""""""":~.,,,,,,~,,-rt_~~,··

.: :

(l.') +++ 'cot""n.J...~,~" I .",'('"_ . , . .. .. . . .~ ~ " . .. .. ,\ ., \A . . o " . . . . ~ " . . , , . ' . .. . .. . . . . . _ , , , -- .. " " ,.. " " " "

at le~et ~ r v z points correctly plotted . . . " " ,. " " " ..

1oin1n" ~p thcrointc to for~n s~ooth curve... 't~ -.- ,. _ ,,, ,. •• :

(ii)

r~ I ' , J c t Cl(..(..IIj)t -Hv *J~ dJ'V ~",~(.e'.(I'-c. ~'pt 'Y.

N.B. 'Utle giver! IUUUt correspond to t:he graph drawnf ';. "r--------~'.--.~.-----.........--~--..------~

+++The rclationsh~p between (O R th e, v ari at io n o f) p er c~ nta gechange in ma ss io f potato strips and concentration ofs uc ro se s ol ut io ns

O R

.The percentage change in mass of potato strips ag~inst(O R ve rs us) su cro se c onc en tr ati on

markse.g.) (i) axis (ii) title++

a .

cotrect ( v r.gainst x ) 1• 1 ' f .,, _ .' -wrQng ( e·G· 2 S a g af ns t y _ ) I, 0 acoer ccponds to axes i.n graph 0. 1

dons not correspond to axes in graph O . 0

correct

correct

wronG

______ -.1.__ •__,.•' , _ _____ ._.. 1 .~

(iii) 7.5% (accept answer-s t.rithi.n the ranee of 7 - 8%) •••••••.•".JU_~

~ ()~"'" ()- M-CY{. C l.( .( .U .A A-l-.e. ~ ~ - J " - C t a (A.t rt~shorten ,the t).mc to a ch L ev e r e c u l t ; e • •• •• •• •• •• •• •• •• •• •• •iv)

bccaucc cur[ncc cree increased for water movement ••••••••

(v) b o L l. Ln g d es tr oy ed c el l E 2. £t 1l bt :1 :. ~! . ' !£m~_~~.e permeabilHy ••

no osmosis :.......................................... 1

!

+20.0 +6.0 -7.0 -20.0-33.5 -40~6 -43.6 j. !

,..... ""-" .--, . . . . --.- . . . . ~.- -------- . . . . . . -,.- .. _ . _ _ ._---,_-. . . , . . - .. _

.

.t,.,': .r 3 1 7 .:7"';:. . .. .. ' . - .

Cqncentration

of sucrose

solution (% )

.2 0s0~(water)

Percentage

change in mass~ ~ ~ . . ~ - - - J - - - ~ - - - - ~ -

1

1

1

1

1

1

1

JI

9

2 S

- - - - - - - - - - - - - - - - - - - - - - - ---------~--'.------



(b) (i)

--7-

(1) (1) B (not named or ,with other letters) " ....... " ........(2) c (not named or with other letter s) ·................(3) G (not named or with other letters) ·................

. ~(4) D (not named or with other letters) ·........... ~....

(ii) for attraCtion I l an di .n g o f i ns ec t ' ( po ll i na to r) ..........protection ........... ' ....................................

(iii)

(iv)

(1) 0 (2) E!

rQ.Ylu.fP. I ,

structure * seed * fruit wall I fruit I pod

function I•

gives risE) t o protects helps in seeda new plarj.t dispersal

(v) (1) both male and female gametes are present / bisexual •..

'..(2) the stigma pro tudes above the anthers / dichogamy I

self sterility ".".""."." "",, .

(vi) offspring from cross-fertilization shows greater genetic

variation "."""."".,,",,. ,'".. ". "" "".. """ " "".

* B - plumule .. ,.. ". "" ". ".. ". """ ". " ". ".I I

* C - cotyledon ;. '.,..

'I e E - budE..,. 1 3 . . \ c \ . ' • . . . . . . . . . . . . . . . . . . . . . . . . . 0 • • • •• • • •

Ie G - stem .: .

(ii) B - it develops into a n~w shoot •••••••••••••••••••••••••

C - it stores/ supplies food for developing new plant •••

(iii) (1) E (not named or with other letters) •••• ~ ••••••••••••

(2) D (not named or with other letters) ••••••••••••••••••

(iv)

(v)

(vi)

(1) A (2) E

cell di vision meiosis mitosis

genotype differen,t same

...............

...............

~

~

~ ~,

~

1

1

o Cl'-'tJfth

'i "

~t ~ C I i

1t 1 . ~ I 0

( l ' V I f twfT

1

1

1

10

~

~

~

~

1

~1

1

1

1,

1,

1

11

overcrowding / compe titLom •••••••••••••••••••••••••••••••



,,'

"

V

3. (c) (i)

(ii)

(1)

(iii)

L,t, t , I,

• ", I,. "~

\, •• ~.1 t,

I' I,I l / : : r : : ' . ' ' '

-8-

fly 3fly 9

fly 10

fly 12

RRrrrr

rr

· .· .· .· " .

flies"

J 8 . 4 has no effect on normal wingstemperature

flies9 8 . 10 has effect on curly wings

(()

Rr •••••••• '•••...••••••......•••••••••••••••••••••••••••••

normal wings ~......................•...... '......... 1

"

1 + 1

1

1 + 1

1

9

,' ,. .. .. . j



; I

, . .

~., (a) (i)

(11)

1I

' II

to ensure that the volume of·air is measured at ,:Iatmospheric pressure / same pressure ••••.•••••••••••••• ~. 1 (~i~~

.. <),c~~ 'I;"'_' ( (W \ A . . W t t r ~ l ~ l , . { .. . .. . .. . . ~,v.-.~ ~

(1) ~~~~~~i~~ ~~~~~~!~).~~~:~~.:~~~~~~~(~~.H..-: ~~•~ . C l t A A { t i

(, ..." l' 11,~.!f." f ,.. ... t - . . , '~ " . , ..

-9-

~\

(2 ).

alkaline pyrogallol / pyrogallic acid solution •••••• 1

(i1i) (1) ,"c o2 % '" ! ! J . • . / . ':f: . . . . . . . . . . " . . . . .'. • . . . . . . . . . . • . . . . . . • 1

(2) 02 % '" 16% .I.(~.................................... 1

• (iv)

(v)

(b) (i)

(11)

f(1) volume (2) composition

change I increase,

littleo or

increase of CO2

in blood

explanation

causing depthincrease o f b re at hi ngin rate

-- -

vital capacity ',

° 1 7

7

0

0

0

0

, } ~ ; · i ~ · ; i ~ ~ ~ ~ ~ i · · · · · · · · · · · · · · · · · · · · · · · · · · ~ · · · · · · · · · ·

• • • • • • • • • • • • • • • • • • • • • • • • • 1 1 t • • • • • • • • • • • • • • • • • • " • • • • • •

(1) tr ans pir at ion r ate > a bs or pt io n ' ra te • •• •• •• •• •• ••

(2)

(3)

water content decreases . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1, 1 (~iiiI ,j

1 ,",

i'~1i I

1

!t ~~, I

t

1i

1

light Jtemperaturerelative humidity .

any T W O • ~ • •• • •• •• • •• •• •• •• • ••

11

1

1

1

1

1 , 1

,(iii)ott M I t

condition effect

(1)< ; I I (to( ~

increase transpiration 1;1- 1pened ..........(2) closing decrease transpiration .......... 1+ 1

(iv) (1) similar shape / same shape I b ot h d ec cr ea se ,a ndthen level out -.................•....

(2) ab sor pt ion e xce eds t ra nsp ir ati on Iabsorption lags behind transpiration Iabsorption and transpiration are interdependent .••..•

1

1

12

•_ u.· .••• _,_ ·, ..-_'_... ,

< .. .. . . ~~" . . . . .. : .. . :. , '. ; . . ,. "' ,_ .. ,. . '"" :'"' . . . . --

. . .



: . .- 10-

"_. 4. (c) (1) ~

A - p ut re fa ct io n/ de co mp os it io n . •• •• .• .• •• •• •• •• •• •• •• •• ••B - nitrification ••••••••.•••••••••••••••••.•••••••••••••

1

1

(ii) to release minerals to soil /

to break down the proteins into simple inorganic cpds., .., 1e . '

* .organisms involved: bacteria

fungi "".".,," ~"".. "". """"". "• ~

" " " " " " " " " " " " " " " " " " " " " " " " " "

(iii) protein.................................................. 1

(iv)/

'M'denitrification/ leaching by soil water . 1 I f ' . . : ' 6 .1

(v) protein or nitrogen absorbed.

is NO T recyale9 / returned~ess available to the 5011 ••1

7



(i)

(ii)

(iii)

(iv)

- l:!-

decrease . . . . . . . . . . . . . . . . . . . . . . . . . . . . ~ .urea had diffused into solution X •••••••••••••••••••••••• 1

!

to maintain normal concentration of plasma ,. . . . . . . . . . . . . . .by preventing ~ diffusion of glucose&/or salt ••••••••• 1

increase the efficiency of urea diffusion

................by allowing gt: ...e.~ter_a r.ea.for diffusi9n •••••••••••••••••••

more urea will diffuse out / less time required •••••••••• 1

I, ', , '.l !

\ ,

. , .

1

" f

1

1

1

1

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7

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1984 Biology Paper I Marking Scheme

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