# Biologi 3 -skema

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```					Skema jawapan biologi                             1

MARKING SCHEME : PAPER THREE – TRIAL BIOLOGY 2010
Question 1 : 1(a)
Score                                           Explanation
Able to record all readings of volume of urine produced

3            Student       Volume of urine in the first   Volume of urine in the
experiment/ml             second experiment/ml
A                  80                           82
B                 150                          170
C                 200                          250
D                 360                          370

2        Able to record any 4-5 volume
1        Able to record any 2-3 volume
0        No response or wrong response

1(b)(i)
Score                                             Explanation
Able to state two correct observations based on following criteria.
C1 – volume of water intake
C2 – volume of urine produced

3
1. When the volume of water intake is 100 ml, the volume of urine produced in
first experiment is 80ml and second experiment is 82 ml.
2. When the volume of water intake is 400 ml, the volume of urine produced in
first experiment is 360 ml and second experiment is 370 ml.

2        Able to state one correct observation and one inaccurate response.
1        Able to state one correct observation or two inaccurate response or idea.
0        No response or wrong response (response like hypothesis)

1(b) (ii)
Score                                            Explanation
Able to state two reasonable inferences for the observation.

1. When the volume of water intake is less, more water is reabsorbed, less urine is
3
produced
2. When the volume of water intake is more, less water is reabsorbed, more urine
is produced

2        Able to state one correct inference and one inaccurate inference.
1        Able to state one correct inference or two inaccurate inference or idea.
0        No response or wrong response (inference like hypothesis)

Peperiksaan Percubaan Biologi SPM 2010
Panitia Biologi Negeri Perlis
Skema jawapan biologi                            2

1(c)
Score                                     Explanation
Able to state all the variables and the method to handle variable correctly
(√) for each variable and method
Manipulated Variable: Volume of water intake     (√)
Method to handle: Repeat the experiment by drinking different volume of water (√)

Responding Variable: Volume of urine produced (√)
3       Method to handle: Measure and record the volume of urine produced after half an
hour by using measuring cylinder.(√)

Controlled variable : type of water intake/ duration to collect urine (√)
Method to handle: . drink same type of water/ fix the time to collect urine (√)

Able to get 6 √ (with the correct key words)
2       Able to get 4 – 5 √
1       Able to get 2 – 3 √
0       No response or wrong response

1(d)
Score                                            Explanation
Able to state the hypothesis correctly based on the following criteria:
V1 – State the volume of water intake
V2 – State the volume of urine produced
3
R - State the relationship between V1 and V2.

The more the volume of water intake, the more the volume of urine produced.
2      Able to state the hypothesis but less accurate.
1      Able to state the idea of the hypothesis
0      No response or wrong response

1(e)(i)
Score                                           Explanation
Able to construct a table and record the result of the experiment with the following
criteria:
– volume of water intake(ml) (√)
– average of volume of urine produced (ml) (√)
- percentage of urine produced (%) (√)

If without unit (x)

3                      Volume of       Volume of urine          Average of
Percentage of
water           produced/ml            volume of
Students                                                             volume of urine
intake/ml      First      Second           urine
produced / %
experiment experiment       produced/ml
A            100          80           76              78                78
B            200         150          170             160                80
C            300         250          250             250                83
D            400         360          370             365                91

2      Able to construct a table and record any two criteria
1      Able to construct a table and record any one criteria
0      No response or wrong response

Peperiksaan Percubaan Biologi SPM 2010
Panitia Biologi Negeri Perlis
Skema jawapan biologi                           3

1(e)(ii)
Score                                              Explanation
Able to draw a bar chart of percentage of urine produced against the volume l of water
intake.
Axes (A) – both axis are labeled with units, uniform scales, independent
variable on horizontal axis. (√)
Point (P) – All points are correctly plotted. (√)
Shape (S) – All bars are correctly drawn (√).

3

2        Graph with any two criteria.
1        Graph with any one criteria.
0        No response or wrong response.

1(f)
Score                                           Explanation
Able to explain the relationship between the volume of water intake and the
volume of urine produced correctly.
3
When the volume of water intake is more, the volume of urine produce also more
because less water is reabsorbed

Able to explain briefly the relationship between the volume of water intake and volume
2
of urine produced
Able to explain the idea the relationship between the volume of water intake and
1
volume of urine produced
0        No response or wrong response

Peperiksaan Percubaan Biologi SPM 2010
Panitia Biologi Negeri Perlis
Skema jawapan biologi                              4

1(g)
Score                                                Explanation
Able to state the definition of urine correctly, based on the following criteria.

C1 – waste product (in the form of liquid)
C2 – excreted by human
3
C3 – influence by volume of water intake

Urine is a waste product in the form of liquid excreted by human and influent by the
volume of water intake
2        Able to state the definition of urine based one of the two criteria.
1        Able to state the idea of urine
0        No response or wrong response

1(h)
Score                                              Explanation
Able to predict correctly and explain the prediction based on the following item:

C1 – the volume of urine produced
C2 – blood osmotic pressure
C3 - reabsorption of water
3
The volume of urine produced is less than 78 ml because after drinking 5% sodium
chloride solution, the blood osmotic pressure increases , therefore more water is
reabsorbed thus the volume of urine produced is less.

2        Able to predict based on any two criteria.
1        Able to predict based on any one criteria.
0        No response or wrong response

1(i)
Score                                                Explanation

Able to classify the apparatus and material used in the experiment

Apparatus                                    Materials
3                      Measuring cylinder                             Plain water
Drinking bottle
Stopwatch

Able to classify all the apparatus and material correctly.

Able to classify two apparatus and one material correctly.
2
Able to classify one apparatus and one material correctly.
1
0        No response or wrong response

Peperiksaan Percubaan Biologi SPM 2010
Panitia Biologi Negeri Perlis
Skema jawapan biologi                           5

Question 2 :

Problem statement
Which water sample is most polluted? /                                    3 marks
Which area contains water that is most polluted?

Aim/objective          To study the level of water pollution in three different water

samples.

Hypothesis
The nearer the area of water sample to the factory/farm, the              3 marks
higher the level of water pollution.

Variables
Manipulative variable: river water samples
Responding variable: time taken for methylene blue solution to
decolourise                                             
Fixed variable: volume of water sample/concerntration of
methylene blue solution

Apparatus and                                                                                All present – 3
materials              Apparatus:      measuring cylinder, stopwatch, reagent bottle,        marks
collecting cup                                        2 materials
and 3-4 app –
Materials : 0.1% methylene blue solution, water samples               2 marks
2 materials
and 2 app – 1
mark

Technique used         Observe and record the time taken by methylene blue solution to
decolourise                                                                   B

Procedure
1. Water sample are collected from three different area by
using collecting cup –KP,KMV                                   8 - 9P – 3 m
2. Three reagent bottles are labelled X,Y and Z and filled with
100 ml of water sample          from village X, Y and Z        6 - 7P – 2 m
respectively.-KFV & KMV
3. The tests are run for all the water samples on the same        3 - 5P – 1 m
day-KP, KFV
4. A syringe is used to add 1 ml of 0.1% methylene blue               3 marks
solution to the base of each the water sample.KP, KFV
5. Make sure the reagent bottles are closed quickly and                   
placed in the dark cupboard.-KC                                KP – Step
6. The stopwatch is started.-KP                                   1,3,4,6,7,9
(any 5)
7. The bottles are examined at 1 –hour intervals- KP, KFV         KMV – Step 1,2
8. The time taken for the methylene blue to decolourise is        KRV – Step 8,
recorded for all the water samples- KRV                        KFV-
9. The results are recorded in the table .KP                      Step2,3,4,7
KC – Step 5

Peperiksaan Percubaan Biologi SPM 2010
Panitia Biologi Negeri Perlis
Skema jawapan biologi                            6

Presentation of        Able to draw a complete table to record the relevant data base
data                   on the 3 criteria:
 Water samples
 Time taken for methylene blue to decolourise
 Level of water pollution

Water sample         X               Y              Z

Time taken for
methylene blue                                                     
solution to
decolourise/min                                                    B

Level of water
pollution

Conclusion
Hypothesis is accepted.
The nearer the water sample to the farm/factory, the higher the
level of water pollution /                                             
The nearer the water sample to the farm/factory, the shorter the
time taken for methylene blue to decolourise

Planning
KB061203               Able to state correctly
8 – 9 aspects (correct) - 3 marks                                   3 marks
6 – 7 aspects (correct) - 2 marks
3 – 5 aspects (corect) - 1 mark
<3                      - 0 mark

Report                 Able to state correctly:
 presentation of data and
 technique.
2 marks
2 correct - 2 marks
1 correct - 1 mark

TOTAL   17 Marks

END OF MARKING SCHEME

Peperiksaan Percubaan Biologi SPM 2010
Panitia Biologi Negeri Perlis

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