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Published by Coet Kms, 2019-11-29 02:37:05

science_process_skill

science_process_skill

Developing Independent Learning in Vibrant Environment

15. Suggestion for modifications

Answer: D

SPS: Identifying and
controlling variables

16. Suggestion for modifications
Answer: D
SPS: Making hypothesis

17. Suggestion for modifications

Answer: C

SPS: Measuring and using
numbers

18. Suggestion for modifications

Answer: D

SPS: Using space-time
relationship

19. Suggestion for modifications
Answer: B
SPS: Interpreting data

20. Suggestion for modifications

Answer: D

SPS: Using space-time
relationship

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Developing Independent Learning in Vibrant Environment

APPENDIX 2

EXPERIMENTAL DESIGN WORKSHEET FOR BIOLOGY

EXPERIMENTAL DESIGN WORKSHEET

Title : Properties of water

Objectives : To study the effect of surface area on heat loss.

Materials/ apparatus

: Beakers (100 ml, 250 ml, 600 ml), hot water (600C), water

heater, thermometer, measuring cylinder, stop watch

Procedure :

1. Place 50 ml of hot water into each beaker respectively

2. Determine the initial temperature of the water

3. Measure the temperature for every two minutes until the

temperature reach 400C

4. Tabulate your observation

5. Plot a proper line graphs (on the same graph) for this

experiment

Questions :

1. State the variables involved in this experiment.

Identify:

Manipulated variables:

Constant variables:

Responding variables:

2. State your hypothesis* for this experiment

Hypothesis is the relationship between manipulated and responding variables.

3. Give the operational definition for heat loss in this

experiment.

4. Analyse the graphs that you have plotted. What is the

relationship between temperature and surface area?

5. From the graphs you have plotted, what can you

conclude from this experiment

6. Extrapolate the graph to determine the temperature

of water after 60 m

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Developing Independent Learning in Vibrant Environment

APPENDIX 3

SUGGESTED ANSWERS FOR PHYSICS EXPERIMENTAL DESIGN
WORKSHEET

Experiment 7 : Simple harmonic motion (SHM)
Apparatus : String (~ 105cm),small pendulum bob, pair of small flat pieces of wood
or cork, retort stand with a clamp, stopwatch, metre rule, protractor,
optical pin, scissors/ cutter, G-clamp

Qa. Manipulated : length of the pendulum, l
Responding : time taken, T
Fixed : amplitude of the oscillation

Qb.

Time taken for 20 oscillations T2/ s2

Reading l/ m t1/ s t2/ s tave/ s T/ s 0.40
0.79
1 0.10 12.6 12.4 12.5 0.63 1.25
2 0.20 0.89 1.56
3 0.30 17.8 17.8 17.8 1.12 1.99
4 0.40 1.25 2.37
5 0.50 22.0 22.8 22.4 1.41

25.0 25.0 25.0

28.2 28.2 28.2

6 0.60 30.6 30.8 30.7 1.54

Qc.

Qd. T2 directly proportional to l
Qe. Periodic motion of a body between two fixed positions without loss of energy
Qf. Vibrating spring
Qg. Switch off the fan while doing experiment// taking a few repeated readings// the
position of eye must be perpendicular to the scale measurements

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Developing Independent Learning in Vibrant Environment

Experiment 9: Sound Waves
Apparatus : Resonance tube, loudspeaker, metre rule, retort stand with two
clamps, rubber tube of at least 1.2 m in length, plastic bottle, signal
generator, rubber stopper with glass tube, thermometer.

Qa. Manipulated : frequency of the signal generator
Responding : length of the air column
Fixed : room temperature

Qb.

Reading f / Hz l/m / ( x 10-3 s )
1 600 7.5 1.67
2 700 6.2 1.43
3 800 4.6 1.25
4 900 3.7 1.11
5 1000 2.5 1.00
6 1100 1.3 0.91

Qc.

Qd. l directly proportional to
Qe. v = 314.68 ms-1, c = -0.056cm
Qf. The actual position of the associated displacement antinodes is a short distance, c

beyond the end known as end correction. The end correction, c occurred as a result
of vibration of
air particles at the end of the resonance tube. Hence, the effective length of a closed
pipe of length, l is therefore (l + c).
Qg. 350.7 ms-1

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Developing Independent Learning in Vibrant Environment

Experiment 11 : Ohm’s Law
Apparatus : D.C. power supply (4 – 6 V), 3 carbon resistors of the same resistance
(100 Ω), D.C. miliammeter or ammeter, D.C voltmeter, resistance box,

switch, connecting wires of about 50 cm long with crocodile clips, 2

connecting blocks for connecting the resistors, screw driver to

loosen/tighten the connecting blocks.

Qa. Manipulated : Resistance

Responding : Voltage and Current

Fixed : Power supply voltage

Qb.

i) Series circuit : ii) Parallel circuit :

Reading V / V l (x 10-3)/ A Reading V / V l/A

1 4.30 15.00 1 2.40 0.05
2 4.35 16.00 2 2.60 0.06
3 4.40 17.00 3 2.80 0.07
4 4.50 18.00 4 3.00 0.08
5 4.60 19.00 5 3.20 0.09
6 4.70 20.00 6 3.40 0.10

Qc.
i) ii)

Qd. Series : 288.04Ω, Parallel : 36.35Ω
Qe. - using the digital ammeter for accurate reading.

- setup the apparatus carefully and make sure all the wire is connecting properly.
- parallax error must be avoided during this experiment.
- take the repeat value to obtain the average value.
- make sure using the suitable apparatus during take the value

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Developing Independent Learning in Vibrant Environment

Experiment 15 : Geometrical Optics
Apparatus : Convex lens, short transparent ruler, piece of card with hole, screen,
light source, metre rule, lens holder

Qa. Manipulated : Object distance, u
Responding : Image distance, v
Fixed : Height of the object, ho

Qb. festimated = 11.0 cm
Qc.

Reading Object distance, u / m Image distance, v / m Magnification, M

1 35.00 25.50 0.73

2 30.00 28.50 0.95

3 25.00 30.00 1.20

4 20.00 39.50 1.98

5 15.00 52.50 3.50

Qd.

Qe. fexperiment = 10.19cm
Qf. The focal length obtained from the experiment is 10.19 cm (from the gradient of the

graph). Compared to the focal length of the infinity light, which is 11.0 cm, the focal
length obtained
is unequal.
Qg. - Make sure the light source is place parallel with the lens and the object.

- Make sure the observer’s eyes perpendicular to the reading scale

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Developing Independent Learning in Vibrant Environment

ANSWERS FOR BIOLOGY PRE-LAB QUESTIONS
EXPERIMENT 4: TRANSPORT ACROSS MEMBRANE

Part A.
1. What do you expect to happen to the net movement of water in the potato cells in:

a) isotonic solution: No net movement of water.
b) hypotonic solution: Water enters the potato cells.
c) hypertonic solution: Water leaves the potato cells.

2. Construct hypothesis to relate the length /size/ mass of potato strips with the different
concentration of solution?
Different concentration of solution affect the length/ size/mass of potato strip.
The length/size/mass of potato strip changes in different concentration of solution.

3. Determine the variables involved in this experiment.
a) manipulated variable: Different concentration of sucrose solution.
b) responding variable: in length/ size/mass of potato strip.
c) constant variables: Volume of sucrose solution, potato strips.

4. What is the operational definition for the net movement of water in this experiment?
The changes in the length/size/mass of potato strips.

5. You are asked to plot a graph to show the changes in weight/length of the potato strips
against molarities of sucrose solution, suggest how do you determine the sucrose
concentration that is isotonic the potato cells.
We can determine the sucrose concentration that is isotonic to the potato cells,when the
line drawn intersect the X axis.(The value of X axis , when Y= 0)

6. What is the purpose of plotting the standard graph?
The standard graph will helps us to determine the osmotic pressure of the potato strips in
atm (atmosphere).

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Developing Independent Learning in Vibrant Environment

EXPERIMENT 15: BIOCATALYSIS
EXCERCISE 15.1

Qualitative test for catalase activity
1. What will you observe when catalase reacts with hydrogen peroxide?

Bubbles produced / effervescences

2. What is the operational definition for the enzyme activity in this experiment?
Vigorous reaction takes placed

3. How do you set a controlled experiment and determine its variable.
By setting the same experiment without the addition of enzymes stock solution.
a) manipulated variable: enzymes stock solution
b) responding variable: bubbles produced
c) constant variables: amount of H2O2

4. Relate the released of bubbles with the activity of the enzyme?
Catalase breakdown the hydrogen peroxide into oxygen and water. When the reaction is
vigorous the enzymes activity is higher.

Quantitative test for catalase activity
5. What is the operational definition for the enzyme activity in this experiment

The amount of KMnO4 used.

6. Not all the H2O2 will be broken down. The leftover can be measured using KMnO4.
Relate the amount of KMnO4 used with the activity of catalase.
The more KMnO4 used indicates that more H2O2 is present in the mixture /H2O2 is not
fully broken down by catalase. Therefore the activity of catalase is low.

EXCERCISE 15.2
Factors affecting the activity of catalase
7. Construct the hypothesis for each factor

Times taken affect the amount of KMnO4 used/ Different temperatures affect the amount
of KMnO4 used/ Different pH affect the amount of KMnO4 used.

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Developing Independent Learning in Vibrant Environment

8. Determine the variables involved in each experiment.
a) manipulated variable
b) responding variable
c) constant variables

Factors Manipulated Responding Constant Variables

Variable Variable

time time amount of Amount of H2SO4/ Amount of enzyme
KMnO4 used - H2O2 mixture/ Temperature/ pH

temperature temperature amount of Amount of H2SO4/ Amount of enzyme
KMnO4 used - H2O2 mixture/ Time/ pH

pH pH amount of Amount of H2SO4/ Amount of enzyme
KMnO4 used - H2O2 mixture/ Time/ Temperature

9. Design an experiment to observe the effect of substrate concentration towards the
enzyme activity

Factors Manipulated Responding Constant Variables

Variable Variable

Substrate Volume of amount of Amount of H2SO4
concentration H2O2 KMnO4 used Amount of enzyme -
H2O2 mixture
Temperature
pH
Time

Record the observation in the table given.
Volume of H2O2
Amount of KMnO4 used

Plot a graph to show the effect of substrate concentration against catalase activity.

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Developing Independent Learning in Vibrant Environment

EXPERIMENT 16: CELLULAR RESPIRATION
1. What is the operational definition for the redox reaction in this experiment?

The colour changes in methylene blue.

2. Construct the hypothesis for this experiment in each boiling tube.
a) Boiling tube A
Heated boiling tube at initial stage affect redox rection in yeast.
Temperature affect redox reaction/ colour changes in methylene blue.
b) Boiling tube B
Redox reaction affect the colour changes in methylene blue .
c) Boiling tube C
High temperature affect redox reaction/colour changes in methylene blue.

3. Determine the variables involved in this experiment.
a) manipulated variable: temperatures
b) responding variable: colour changes in methylene blue
c) constant variables: volume of yeast suspension used// amount of methylene blue

4. What is the purpose of boiling tube C. Explain your answer.
Acts as a control. Tube C shows that high temperature affect redox reaction. No colour
changes occur after heating of boiling tube C. This indicates that enzymes has been
denatured.

5. Vigorous shaking will change the yeast’s mode of respiration. Relate this activity with
redox reaction.
Vigorous shaking causes the depletion of oxygen. Therefore yeast undergoes anaerobic
respiration. Methylene blue is oxidized as shown by the changed in colour.

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Developing Independent Learning in Vibrant Environment

EXPERIMENT 17: PHOTOSYNTHESIS
1. Determine the variables involved in this experiment.

a) manipulated variable: types of leaves used
b) responding variable: distance moved by pigment from its origin// different colour of

pigment
c) constant variables: solvent used// amount of fresh leaves used

2. Why different plants leaves are used in this experiment? Construct the hypothesis for this
experiment.
Different leaves have different types of pigment / same pigment
Hypothesis
Different leaves extract contained different types of pigment / same pigment
Different pigments have different Rf values.

3. Chromatography is a technique that separate plants pigments based on the molecular
weight of the pigment. What is the operational definition of the molecular weight in this
experiment?
Distance moved by the pigment from its origin/ different colours of photosynthetic
pigments

4. Rf value is defined as the ratio of the distance travelled by a pigment to the distance
traveled by the solvent. It measures how far the compound has moved. If a compound is
large (high molecular weight) the solubility will be less that of a compound with a low
molecular weight. Relate the Rf value (refer Table 17.1) with the molecular weight of each
pigment.
Rf value depends on the distance moved by the pigment from its origin. The higher the
molecular weight of the pigment the shorter is the distance . Therefore the Rf value is
low. The lower the molecular weight of the pigment the longer is the distance Therefore
the Rf value is high.

5. Predict the distance moved by the pigments if different solvent is used.
The distance moved will differ, therefore the Rf value changed.(even though the same types
of leaves used

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Developing Independent Learning in Vibrant Environment

DELIVER: Developing Independent
Learning in Vibrant Environment
Centre of Excellent in
Teaching

www.kms.matrik.edu.my

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