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Science Stage 9 02 MS 8RP AFP tcm143-639994 (2)

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Science
Stage 9
Paper 2
Cambridge Lower Secondary Progression Test
Mark Scheme
3146_02_MS_8RP
© UCLES 2022
2022
S9/02
Science Stage 9 Paper 2 Mark Scheme
2022
General guidelines on marking
Many descriptive answers can be expressed in a variety of ways. Professional judgement can be
used in these cases, providing it matches the marking points and further information in the mark
scheme.
Answers may have words spelt incorrectly. Credit is normally given for phonetically correct answers,
unless the word has a scientifically different meaning. For example, where the answer should be
antennae, credit will be given for antena but not for anthen (too close to anther).
Only the science is being assessed, so answers do not need to be grammatically correct.
Significant figures will be indicated in the question or in the mark scheme.
Unless specified all marking points are independent.
Annotations and abbreviations
/ or
alternate responses for the same marking point
( ) brackets
the words or units in brackets do not need to be stated, for example, (recycles or
releases or provides) minerals = minerals scores the mark
underline
exact word is required
Accept
an acceptable response
Do not accept
indicates an incorrect response that would contradict another otherwise correct
alternative
Ignore
indicates an irrelevant answer that is not creditworthy. Full marks can still be
achieved even with answers that are ignored.
Note
provides extra information when necessary
ecf
error carried forward; marks are awarded if an incorrect response has been carried
forward from earlier working provided the subsequent working is correct
ora
or reverse argument; for example, as mass increases, volume increases could be
written as mass decreases, volume decreases
© UCLES 2022
Page 2 of 10
© UCLES 2022
Page 3 of 10
leaving the blood without any toxic substance / (membrane)
does not allow blood through
the toxic substance goes through the (partially permeable)
membrane
urine is stored here before excretion from
body
bladder
1(c)
urine travels through this tube to be stored
ureter
filters (the blood)
blood enters excretory (renal) system
renal artery
kidney
what happens
part
Answer
urea
Question
Marks
Science Stage 9 Paper 2 Mark Scheme
1(b)
1(a)
S9/02
Accept the (partially permeable) membrane only
lets the toxic substance through = 2 marks
Accept the (partially permeable) membrane
lets the toxic substance through but not the
blood = 2 marks
Accept urea for toxic substance
Accept blood is purified
2 each correct answer = 1 mark
1
Accept (ultra)filtration
3 each correct answer = 1 mark
Further Information
2022
attraction between positive and negative ions
801 °C
3(b)(ii)
3(b)(iii)
Page 4 of 10
ionic / electrovalent
3(b)(i)
© UCLES 2022
sodium (atom) loses an electron
Answer
Answer
Marks
Marks
Science Stage 9 Paper 2 Mark Scheme
3(a)
cancellation
2(b)(ii)
increases
stays the same
reinforcement
Question
Question
2(b)(i)
2(a)
S9/02
Accept any indication of the correct answer, e.g.
ticking or underlining, but circling takes
precedence
1 more than one answer circled = 0 marks
1 Accept electrostatic attraction between ions
1
1 Accept electron(s) lost
Further Information
1 Accept destructive interference
1 Accept constructive interference
2 each correct answer = 1 mark
Further Information
2022
(prediction)
(the two large pieces of biscuit) will move (apart)
4(b)(ii)
© UCLES 2022
4(c)
4(b)(iv)
4(b)(iii)
(Earth’s) core
4(b)(i)
Page 5 of 10
climate change / increase in global temperature / increase in
carbon dioxide in atmosphere / increase in sulfur dioxide in
atmosphere / (idea that) oxygen levels reduced
position of volcanoes
alignment of magnetic materials in the Earth's crust
fossil record
jigsaw appearance of continental coasts
(idea that) earthquakes occur at plate boundaries
(earthquakes) result from movement of plates
(explanation)
convection current (moves the biscuits/plates)
(tectonic plates) are less dense than the mantle
4(a)(ii)
Answer
crust
Question
Marks
Science Stage 9 Paper 2 Mark Scheme
4(a)(i)
S9/02
Accept leads to an ice age with no reference to
global warming in the answer
1 Accept blocks sunlight
2 each correct answer = 1 mark
2 each correct answer = 1 mark
2 each correct answer = 1 mark
1
1 Accept less dense than magma
1 Accept lithosphere
Further Information
2022
36
38
gestation period
in weeks
40
© UCLES 2022
increase sample size
2.4
34
2.8
5(b)
birth mass
in kg
3.2
3.6
Answer
(birth mass is) decreased by smoking
Question
Page 6 of 10
42
key
non-smokers
smokers
Marks
Science Stage 9 Paper 2 Mark Scheme
5(a)(ii)
5(a)(i)
S9/02
1
1 Accept as gestation period increases, birth mass
increases
more than one point circled = 0 marks
1 Accept other correct indications of the anomalous
point but circling takes precedence
Further Information
2022
Question
© UCLES 2022
8(c)
8(b)
8(a)
7
Answer
population
Page 7 of 10
1
Accept reduced fecundity
(without sperm) no fertilisation takes place
2 each correct answer = 1 mark
Accept 23 is the haploid number for humans
= 2 marks
2 each correct answer = 1 mark
Further Information
3 each correct answer = 1 mark
Further Information
1 Accept Rb but name takes precedence
1
1
Further Information
Accept sperm not viable
Marks
Marks
Marks
(higher temperatures) reduce sperm production
(idea that sperm cell has) half the number of chromosomes
of a fertilised egg cell
23
decreases
thermal
evaporate
Answer
rubidium
6(c)
Question
any value in the range 550 to 650 (°C)
6(b)
Answer
any value in the range 105 to 200 (°C)
Question
Science Stage 9 Paper 2 Mark Scheme
6(a)
S9/02
2022
Question
© UCLES 2022
9(c)
9(b)
9(a)
S9/02
Accept (hydrochloric acid) burns the skin/eyes
hydrochloric acid is corrosive/harmful
2 each correct answer = 1 mark
Accept more frequent collisions with powder
2 each correct answer = 1 mark
Do not accept name of incorrect gas is
lost/released
Ignore water vapour is lost
Accept a reading less than 102.34 g
2 each correct answer = 1 mark
Further Information
Ignore facemask
Marks
2022
wear goggles/gloves
Page 8 of 10
more collisions with powder / fewer collisions with lumps
powder has a greater surface area / lumps have a smaller
surface area
as carbon dioxide/gas is lost/released (from the equipment)
(reading on balance) gets less / decreases / reduces
Answer
Science Stage 9 Paper 2 Mark Scheme
Question
© UCLES 2022
10(b)
10(a)(ii)
10(a)(i)
S9/02
(idea that) current divides/splits
V
Page 9 of 10
correct symbol for voltmeter connected in parallel with lamp
e.g.
A
correct symbol for ammeter connected in series with cell
and lamp
e.g.
Answer
Marks
Science Stage 9 Paper 2 Mark Scheme
1
1
1
Further Information
2022
Question
© UCLES 2022
11(b)
11(a)
S9/02
Page 10 of 10
add to water and record if they float or sink
use objects of the same shape/size
measure the density of a range of different plastic objects
any two from
objects with a density less than cooking oil or 0.9 g / cm3 will
float
objects with a density greater than cooking oil or 0.9 g / cm3
will sink
any one from
Answer
Marks
2022
Accept ice will remain suspended as its density is
the same as cooking oil
Further Information
2 each correct answer = 1 mark
1
Science Stage 9 Paper 2 Mark Scheme
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