FOCUS SPM Science (2023)

Format 190mm X 260mm Extent : 424pg (18.66mm) Confirmed = 1.8mm (40pg/4C/70gsm) + 15.36mm (384pg/2C/60gsm) + 1.5 mm Status CRC Date 28/2

PELANGI BESTSELLER




SPM
CC038943



FORM KSSM FOCUS
4∙5
Science SPM


Science SPM





FOCUS SPM KSSM Form 4 • 5 – a complete and precise series of reference books
with special features to enhance students’ learning as a whole. FORM
This series covers the latest Kurikulum Standard Sekolah Menengah (KSSM) and
integrates Sijil Pelajaran Malaysia (SPM) requirements. (Dual Language Programme) 4∙5 KSSM
A great resource for every student indeed!
• Nor Mazliana Abdul Hashim*
REVISION REINFORCEMENT EXTRA Science • Mohammad Amirul Adnan*
• Noraini Abdullah*
› Infographics & ASSESSMENT FEATURES • Lau Pik Ying Exclusive!
› Comprehensive Notes › SPM Practices › Mastering A+ Techniques • Sabariah Hakim Mastering A+
› Concept Maps › SPM Model Paper for SPM Science • Nilavathi Balasundram
› Activities & › Checkpoint › SPM Highlights • Zuraini Abdul Razak Techniques for
Experiments › Complete Answers › Digital Resources QR Codes • Noorhaida Sukardi SPM Science
› SPM Tips › Examples
*Textbook Writer


TITLES IN THIS SERIES
• Bahasa Melayu • Matematik • Mathematics
• Karangan • Matematik Tambahan • Additional Mathematics FORM 4•
• English • Sains • Science
• Bahasa Cina • Biologi • Biology
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CC038943
ISBN: 978-629-7537-79-5
Based on the
LATEST SPM FORMAT
PELANGI

Mastering A+






Techniques for




SPM Scienc e
SPM Science









SCIENCE PROCESS SKILLS THAT ARE TESTED:

ing
imen
t
Exper
Experimenting
11 (a) State one problem statement from
the information provided.
[1 mark]
Question 11(a) and (b)
(b) Suggest one hypothesis to Refer to the given
investigate the above statement. situation
[1 mark]
(c) Design a laboratory experiment to
test the hypothesis.
(i) State the aim of the experiment
[1 mark] Question 11(c)
(ii) Identify the variables Based on a planned
[2 marks] experiment (using the
(iii) Procedure or method materials and apparatus
[4 marks] given in the question)
(iv) Tabulation of data
[1 mark]






















T1

11(a) State one problem statement from the information provided.



1
1 2 3
3
2
Step Step Step
READ and FIND and FIND and
UNDERSTAND UNDERLINE the UNDERLINE the
the STATEMENT MANIPULATED RESPONDING
or SITUATION or VARIABLE MV VARIABLE RV
FACT given in the given in the given in the
question. question. question.


Paragraph TIPS TIPS
What is different a. Experimental
results/
Figure What is replaced observations

b. The outcome
Dialogue of changing

the MV









IMPORTANT TIPS
IMPORTANT TIPS

a. MUST be written in
QUESTION FORM and end
with a QUESTION MARK (?)
b. START THE SENTENCE with
a QUESTION WORD
How
Is there
What













T2

Format: 190mm X 260mm TP Focus SPM 2023 Sc BI version _pgi (2C) CRC











Science SPM





FORM
4∙5
(Dual Language Programme) KSSM





• Nor Mazliana Abdul Hashim*
• Mohammad Amirul Adnan*
• Noraini Abdullah*
• Lau Pik Ying
• Sabariah Hakim
• Nilavathi Balasundram
• Zuraini Abdul Razak
• Noorhaida Sukardi
*Textbook Writer








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permission of Penerbitan Pelangi Sdn. Bhd.



ISBN: 978-629-7537-79-5
eISBN: 978-629-7537-80-1 (eBook)


First Published 2023




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Exclusive Features of This Book




Theme 1: Scientific Methodology Form 4
Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health
Chapter Techniques of Measuring the
Chapter Focus 3 Parameters of Body Health Solving Problems involving Speed, Average
lists the learning Life Speed, Velocity and Acceleration in Daily Example 11.4 Science SPM Chapter 11 Force and Motion
A
van
Example 11.2
accelerates
objectives for an Ah Kim pedals his bicycle 250 m from his house uniformly from a velocity
of 10 m s –1 to 20 m s –1
in 2.5 s. What is the
acceleration of the van?
to Rahim’s house. Ah Kim takes 50 seconds to
pedal his bicycle? Solution: Figure 11.4 Example
arrive at Rahim’s house. How fast does Ah Kim
Form
overview of the 4 Solution: Time Time taken, t = 2.5 s
Initial velocity, u = 10 m s –1
Speed = Distance
Final velocity, v = 20 m s –1
chapter. = 5 m s -1 Acceleration, a = = 4.0 m s –2 2.5 s 4 Form provides solution
= 250 m
50 s
20 m s –1 – 10 m s –1

Example 11.5 for example of
Example 11.3
questions in the
A participant runs from starting point O to P which
A cow walked along a curved path from P to Q,
is 100 m to the north of O. The participant then runs
which is 70 m away from P. Q lies to the southwest
to point Q which is 100 m to the east of P. The total
(S 45° W) of P. The distance travelled by the cow
subtopics.
is 240 m and the time taken is 160 s.
time taken by the participant is 25 seconds.
P
N 100 m N
Q
100 m
CHAPTER FOCUS Q O Figure 11.5
P
Body Temperature Calculate the Figure 11.3 What is the (a) distance, (b) average speed,
Pulse Rate (a) average speed, and participant?
Blood Pressure of the cow moving from P to Q. Solution: Infographic
(c) displacement and (d) average velocity of the
(b) average velocity
Checkpoint Body Mass Index (BMI) Displacement = 70 m (a) Total distance travelled by the participant
Solution:
= 100 m + 100 m = 200 m
Total distance travelled = 240 m
(b) Average speed
provides questions Athletes have pulse rates lower Time taken = 160 s Time taken (c) Resultant displacement of participant from point O visually highlights
individuals
non-athletic
Total time
than
the key concepts
25 s
because an athlete's cardiac
= Total distance = 200 m = 8 m s –1
(a) Average speed = Total distance travelled
= 240 m
to test students’ muscle is stronger. Access to (b) Average velocity = Displacement = 70 m (d) Average velocity of each chapter to
In addition to the pulse rate,
= 100 2 + 100 2
160 s
= 100 2 m
what are the other important
= 1.5 m s –1
parameters to measure the level
= Displacement
Time taken
160 s
understanding of of our health? INFOGRAPHIC = 0.44 m s –1 to the southwest = 100 2 Total time = 4 2 m s –1 enhance students’
of P
25
the subtopics and 22 22 Science SPM Chapter 2 Nutrition and Food Technology in the direction N 45° E of point O.
2.2
reinforce learning. SPM Tips Q1 (a) What are macronutrients? List two examples Science SPM Chapter 5 Genetics 159 learning.
Checkpoint
of macronutrients.
(b) What are micronutrients? List two examples
The following figure shows the effects of nitrogen, Q2 State one effect of deficiency for each of the SPM Practice 5
phosphorus and potassium deficiency on plants.
of micronutrients.
(a) Nitrogen
Yellowed following nutrients. (c) Potassium Objective Questions
Q3 In an experiment to study the effects of nutrient 1. Why is the mitosis process 5. Which of the following is
leaves (b) Phosphorus
deficiency of nutrients in plants, why is it
important for living
organisms?
necessary to
(a) cover the boiling tube with black paper? Form A To produce variation caused by gene mutation? 9. Mrs. Dewi has been
A Albinism
(b) blow air into the culture solution? B To form male and female B Down syndrome pregnant for 18 weeks. The
4
gametes for fertilisation C Klinefelter syndrome doctor needs to check if the
(a) Nitrogen deficiency C For cell growth and to D Turner syndrome baby is free from any genetic
SPM Tips 2.3 Nitrogen Cycle D To ensure every daughter 6. Study the statement below. suitable for Mrs. Dewi and SPM Practice
disorders disease. Among
replace injured or dead
cells
the following methods of
treatment, which is most
A sperm that carries a
1. Nitrogen is required to form proteins and
her baby?
cell receives half the
points out The edges of the Stunted growth Nitrogen Cycle of the parent cell What is the chromosome of B Genetic genealogy provides ample
22 + X chromosome is
number of chromosomes
nucleic acids in living organisms.
A Gene therapy
fertilised with an ovum.
leaves curl and
2. Nitrogen exists in different forms in nature. It
turn brown
and weak root
exists most commonly in gaseous state.
the child?
C Amniocentesis
important tips for Leaves turn dark (b) Phosphorus deficiency system 3. Despite making up 78% of atmospheric air, 2. Figure 1 shows a pair of D 44 + XY 10. Figure 2 shows a bar chart questions to test
chromosomes.
A 22 + X
green with purple
D Karyotyping
plants are unable to use this gaseous form of
edges
B 44 + XX
C 22 + Y
students to take Yellow spots 4. Plants can only use nitrogen in the form of 7. Curley-haired Kumar, Rr; Number of representing a type of students’ mastery
variation.
nitrogen.
forming on the
students
nitrate ions that are dissolved in soil water.
leaves
married to Suganthi with
a component of protein in the tissue of plants
note of. Soft stem Necrotic tissues The nitrate ions absorbed by plants become A Centriole Figure 1 hair? straight hair, rr. If they have of the chapter.
on the shoots
three children, what is the
What is R?
and edges
and animals.
ratio of children with curly
of leaves
hair to those with straight
(bacteria) will break down proteins into
B Chromatids
A 1 : 1
ammonium compounds through the process
C Centromere
(c) Potassium deficiency 5. When plants and animals die, decomposers Form 5 D Spindle fibre C 3 : 1 Figure 2 Trait
B 2 : 1
of decay. Nitrifying bacteria will then convert
in the soil. Some nitrate may decompose and
D 1 : 3
Which of the following is
SPM Highlights ammonium compounds to nitrites and nitrates 3. Among the following organs, 8. David is colour blind. He B Type of blood
represented by Figure 2?
A farmer found his mango tree with the following
where does meiosis occur?
form nitrogen gas again.
A Height
A Kidneys
B Heart
married his wife, Jane, who
C Ovaries
into nitrate ions in the soil naturally via
SPM Highlights symptom: Low fruit yield 6. Nitrogen gas in the atmosphere always turn 4. What is the number of What is the probability of 11. Suzi went to a hair saloon
C Type of finger print
Which element is required in the fertiliser to overcome
D Colon
is a carrier of the colour blind
gene.
D Type of ear lobe
multiple processes.
D Potassium
A Phosphorus
chromosomes for an
their children being colour
converts the nitrogen in the air into nitrate
provides exposure this problem? C Calcium 7. Nitrogen cycle is a natural cycle which individual with Klinefelter A 25% Which of the following factors
to perm her straight hair.
blind too?
B Nitrogen
compounds through plants and animals.
After several months, her
syndrome?
Phosphorus is needed to increase the quantity of
hair become straight again.
Examiner’s Tips
A 44
B 50%
C 46
B 45
C 75%
to the frequently- crop yields. 227 D 47 D 100% influenced this condition? SPM Model
A Environment
Answer: A
B Chromosome mutation
C Gene mutation
D Gene
tested questions 74 Paper
that appear in the Science SPM Chapter 2 Nutrition and Food Technology prepares
Experiment 2.1
Eksperimen 2.1
Eksperimen 2.1
actual exam. Aim: To estimate the calorific value in some food samples using a calorimeter. SPM Model Paper students for the
Problem statement: Which food sample has the highest calorific value?
Hypothesis: Groundnuts have a higher calorific value than bread and anchovies.
PAPER 1
SPM Tips
Variables:
(b) responding: Change in temperature / Calorific value of food
(a) manipulated: Type of food sample The operational definition for calorific 1. Which of the following is used One hour fifteen minutes SPM with the
value in this experiment:
Calorific value is the condition of a
Answer all questions. Each question is followed by four options A, B, C and D. Choose the best option for each question.
greater change in temperature that
(c) constant: Mass of water
Materials: 1 g of groundnuts, 1 g of bread, 1 g of anchovies, cotton occurs when 1 g of groundnuts are A Goggles 4. Which of the following 8. Which of the following occurs actual exam
to protect the eyes when
conducting experiments?
burned completely.
thermometers is the most
wool and distilled water
suitable to measure the body
B Contact lenses
during the metaphase stage in
temperature of an infant?
C Spectacles
mitosis?
D Sunglasses
A Doubling of chromosomes
B Rectal thermometer
plasticine and needle
Activity/ Apparatus: Retort stand, boiling tube, thermometer, shield, Retort stand 2. Figure 1 shows a fire A Clinical thermometer B Formation of new centrioles format.
Thermometer
C Laboratory thermometer
C Arrangement of
Procedure:
D Infrared thermometer
1. The apparatus set-up is prepared as
chromosomes at the cell
extinguisher found in the school
equator
laboratory.
shown in the figure.
Experiment 2. The type of food sample and its mass, Distilled water Red 5. The doctor has informed 9. Which of the following genetic
D Movement of chromosomes
to the cell poles
Mr. Salim that his blood
the mass of water in the calorimeter Boiling tube
pressure is normal. Which of the
and the initial temperature, T 1 , of the
following readings may belong to
Mr. Salim?
thermometer is recorded in a table.
mutation?
diseases related to chromosome
A 110/50 mmHg
A Down syndrome
helps students 3. A lighter is used to ignite the food Groundnuts Viruses C 120/80 mmHg D Thalassaemia
B 135/90 mmHg
4. The final temperature, T 2 after the Shield
B Colour blindness
Plasticine
C Haemophiliac
sample.
D 120/100 mmHg
food sample has burned completely is
Figure 2.4 Apparatus set-up
observed and recorded in the table.
to master hands- 5. The calorific value of the food sample is 4.2 × Mass of water × Change in water temperature extinguisher? Figure 1 DNA 6. Which of the following is the 10. Figure 2 show two graphs for
application of Green Technology
blood type and body weight of
students in Form 4 Harmoni.
What is the type of fire
in the transportation sector?
calculated using the formula:
A Using leaded petrol
Protein
coat
A Foam extinguisher
B Using biofuel
Science SPM Chapter 1 Microorganisms
on scientific Calorific value of food (kJ g –1 ) = Mass of food × 1000 Bread D Carbon dioxide extinguisher C Using private vehicle DNA Number of individuals
B Water extinguisher
C Dry powder extinguisher
D Limiting the usage of public
transport
Anchovies
Groundnuts
Results:
knowledge and Form 5 Mastering A+ 1 10 1 10 1 10 29 3. Which of the following situations 7. Which of the following explains Protein A B AB O
Bacteriophage
the meaning of genes?
Techniques for
require CPR to be administered?
Food sample
A A gene is a long DNA.
coat
A The victim has a high fever.
Mass of food sample (g)
Influenza virus
B The victim is unconscious
B A gene is the basic unit for
heredity.
and not breathing.
skills. Mass of water (g) 29 29 50 50 D The victim has fallen down C A gene is thin threads inside Blood type Corona virus
SPM Science
C The victim is choking on a
rambutan seed.
the nucleus of a cell.
Tobacco mosaic virus
Initial temperature, T 1 (°C)
Figure 1.10 Examples of viruses
D A gene is the basic building
Final temperature, T 2 (°C) 80 51 21 0.88 21 themselves. • The smallest microorganism Viruses
block for all living organisms.
on stairs and has sprained
• Have no cell organisation
Change in temperature, T 2 – T 1 (°C) 2.14 0.88 • Do not show characteristics of living cells Number of individuals
• Can crystallise
1. The calorific value of a food sample determined using a calorimeter is less than the actual calorific value 384 • Contain nucleic acids (DNA or RNA) and covered in protein sheath Body weight (kg)
Calorific value (kJ g –1 ) • Do not eat, produce waste or grow Model 3D Bacteriophage
• Do not contain cytoplasm, plasma membrane or nucleus
of the food sample. This is due to the loss of some energy to the surroundings in the form of heat.
• Reproduce inside living cells
SCIENCE PROCESS SKILLS THAT ARE TESTED: Size • 0.2 µm to 0.4 µm Figure 2 VIDEO Corona Virus
Discussion:
Shape
Mastery A+ 220 Experimenting Question 11(a) and (b) • Spherical, for example influenza virus Reproduction
11 (a) State one problem statement from
• Reproduces when inside living cells by using the cell’s components Digital Resources*
Refer to the given
• Helical, for example mosaic virus
the information provided.
to produce copies of itself.
• Polyhedral, for example adenovirus
Techniques for SPM (b) Suggest one hypothesis to [1 mark] situation Nutrition example bacteriophage). Bacterium Virus Bacterial DNA Viral help learners
• Complex (combination of helical and polyhedral for

investigate the above statement.
[1 mark]
Science (c) Design a laboratory experiment to Question 11(c) • Do not need food 1 A virus attaches itself DNA 2 The virus injects better comprehend

to a host cell.
Based on a planned
test the hypothesis.
[1 mark]
Habitat
cell’s cytoplasm.
helps students to (i) State the aim of the experiment experiment (using the • Live in host cells its DNA into the concepts and
materials and apparatus
(ii) Identify the variables
given in the question)
[2 marks]



• Form crystals outside a living cell
[4 marks]
develop the skills (iii) Procedure or method Many virologists view a virus as a non-living 3 material in the host cell. 5 Form deepen learning.



SPM Tips
(iv) Tabulation of data
The viral DNA replicates using
[1 mark]


The viral DNA then makes its
needed to excel in host cell. 5 The host cell bursts to own outer protein coat. *3D model/Interactive
small particle because it does not have a cell
membrane and does not undergo metabolic
processes like other microorganisms. Viruses
only undergo metabolic processes and
are considered “alive” when inside the
release hundreds of new
SPM Science Paper 2. other cells. Figure 1.11 Virus replication chart/Video/Info
viruses which will infect
4
New viruses formed
197
T1
ii
00 Xclusif Sci SPM.indd 2 24/02/2023 1:37 PM

CONTENTS







FORM 4

Chapter Support, Movement and
Theme 1 Scientific Methodology 6 Growth 77
6.1 Support, Movement and Growth
Chapter Safety Measures in the in Animals 78
1 Laboratory 1 6.2 Human Movement and Growth 86
6.3 Support, Growth and Stability in Plants 91
1.1 Personal Protective Equipment 2
1.2 Disposal of Waste 4 SPM Practice 6 97
1.3 Fire Extinguishers 7
SPM Practice 1 12 Chapter
7 Body Coordination 100
Chapter
2 Emergency Help 14 7.1 Human Endocrine System 101
7.2 Disruptions to Body Coordination 105
2.1 Cardiopulmonary Resuscitation (CPR) 15 7.3 Healthy Mind 109
2.2 Heimlich Manoeuvre 17 SPM Practice 7 112
SPM Practice 2 20


Chapter Techniques of Measuring the
3 Parameters of Body Health 22 Theme 3 Exploration of Elements in
Nature
3.1 Body Temperature 23
3.2 Pulse Rate 25 Chapter
3.3 Blood Pressure 29 8 Elements and Substances 115
3.4 Body Mass Index (BMI) 31
SPM Practice 3 34 8.1 Matter 116
8.2 Modern Periodic Table of Elements 118
Maintenance and Continuity 8.3 Isotope 122
Theme 2 SPM Practice 8 125
of Life
Chapter Green Technology for
4 Environmental Sustainability 36 Chapter
4.1 Environmental Sustainability 37 9 Chemicals in Industry 128
4.2 Energy Sector 39 9.1 Alloy 129
4.3 Waste and Wastewater Management Sector 41 9.2 Glass and Ceramic 134
4.4 Agriculture and Forestry Sector 44 9.3 Polymer 136
4.5 Transportation Sector 45 SPM Practice 9 141
4.6 Green Technology and Life 46
SPM Practice 4 48
Chapter
Chapter 10 Chemicals in Medicine and 143
5 Genetics 51 Health
10.1 Traditional Medicine, Modern Medicine
5.1 Cell Division 52 and Complementary Medicine 144
5.2 Inheritance 59 10.2 Free Radicals 150
5.3 Mutation 64 10.3 Antioxidant Substances 151
5.4 Genetic Engineering Technology 69 10.4 Health Products 152
5.5 Variation 71 SPM Practice 10 154
SPM Practice 5 74




iii






00 Content SC SPM.indd 3 24/02/2023 1:38 PM

Chapter
12 Nuclear Energy
Theme 4 Energy and Sustainability of Life 180
Chapter 12.1 The Use of Nuclear Energy 181
11 Force and Motion 156 12.2 The Production of Nuclear Energy 183
12.3 Impact of Using Nuclear Energy 186
11.1 Linear Motion 157 12.4 Nuclear Energy in Malaysia 188
11.2 Linear Motion Graphs 165 SPM Practice 12 190
11.3 Gravitational Acceleration and Free Fall 169
11.4 Mass and Inertia 172
SPM Practice 11 176


FORM 5

Maintenance and Continuity Chapter
Theme 1 5 Carbon Compounds 288
of Life
Chapter 5.1 Introduction to Carbon Compounds 289
1 Microorganisms 193 5.2 Hydrocarbons 291
5.3 Alcohol 296
1.1 World of Microorganisms 194 5.4 Fats 303
1.2 Useful Microorganisms 206 5.5 Palm oil 305
1.3 Prevention and Treatment of Diseases SPM Practice 5 315
Caused by Microorganisms 209
SPM Practice 1 213 Chapter
6 Electrochemistry 320

Chapter 6.1 Electrolytic Cell 321
2 Nutrition and Food Technology 216 6.2 Chemical Cell 333
SPM Practice 6 337
2.1 Balanced Diet and Calorific Value 217
2.2 Nutrient Requirements in Plants 223
2.3 Nitrogen Cycle 227 Theme 3 Energy and Sustainability of Life
2.4 Food Production Technology 229
2.5 Food Processing Technology 233 Chapter 339
2.6 Health Foods and Health Supplements 237 7 Light and Optics
SPM Practice 2 240 7.1 Formation of Images by Lenses 340
7.2 Optical Instruments 347
Chapter Sustainability of the SPM Practice 7 353
3 245
Environment
Chapter
3.1 Product Life Cycle 246 8 Force and Pressure 357
3.2 Environmental Pollution 251
3.3 Preservation and Conservation of the 8.1 Pressure in Fluids 358
Environment 256 SPM Practice 8 367
SPM Practice 3 260
Theme 4 Earth and Space Exploration
Exploration of Elements in
Theme 2 Chapter
Nature
9 Space Technology 371
Chapter
4 Rate of Reaction 264 9.1 Satellite 372
379
9.2
Global Positioning System (GPS)
4.1 Introduction to Rate of Reaction 265 SPM Practice 9 382
4.2 Factors Affecting Rate of Reaction 270
4.3 Applications of the Concept of Rate of SPM MODEL PAPER 384
Reaction 280
SPM Practice 4 284 ANSWERS 395



iv






00 Content SC SPM.indd 4 24/02/2023 1:38 PM

Theme 1: Scientific Methodology Form 4
Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health
Chapter
3 Techniques of Measuring the


Parameters of Body Health










Form
4





















CHAPTER FOCUS



Body Temperature
Pulse Rate
Blood Pressure
Body Mass Index (BMI)





Athletes have pulse rates lower
than non-athletic individuals
because an athlete's cardiac
muscle is stronger.
What are the other important
health parameters, in addition
to pulse rate, that should be
measured to assess our overall
health?

Access to
INFOGRAPHIC




22
22





03 F4 Focus SC SPM.indd 22 24/02/2023 1:40 PM

Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health

3.1 Body Temperature 5. Our body temperature is controlled by the
hypothalamus in the brain.
6. Body temperature keeps our body functioning
1. Temperature is a measurement of the degree optimally.
of hotness and coldness of a substance.
7. A tool used to measure temperature is a
2. Body temperature is the measurement of the thermometer.
degree of hotness and coldness of the body.
8. There are many types of thermometers with
3. A normal human body temperature is 36.9°C.
different functions.
4. The increase and decrease of our body 9. Table 3.1 shows four types of thermometers Form
temperature shows that we may have health that are commonly used.
problems. 4

Table 3.1 Types of thermometers and their functions
Clinical thermometer Laboratory thermometer
















• Used to measure body temperature • Used to measure the temperature of liquids
• Measure temperatures in the range of 35°C − 42°C • Not suitable for measuring body temperature
• Can measure temperature with a precision of 0.1°C • Measure temperatures in the range of -10°C − 110°C
• Can measure temperature with a precision of 1°C

Rectal thermometer Infrared thermometer


















• Used to measure body temperature through the anus • Used to measure body temperature without contact
with the body
• Usually used for infants below 3 months
• Temperature reading using this thermometer is very
quick




23






03 F4 Focus SC SPM.indd 23 24/02/2023 1:40 PM

Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health
Measuring Body Temperature with the (c) Apply petroleum jelly on the thermometer
Correct Technique bulb to make it easier to put in the baby's
anus.
1. Clinical thermometer
(d) Lay the baby down and the lift the feet.
(a) Make sure the temperature of the
thermometer is below 35°C before use. (e) Enter the thermometer into the baby's anus
about 1.5 cm to 2.5 cm.
(b) Shake the thermometer if the temperature
is over 35°C.
(c) Place the thermometer below armpits or
under the tongue for about 2 to 3 minutes.
Form
(d) Remove the thermometer and take the
4
temperature readings.
2. Laboratory thermometer
(a) Laboratory thermometer is not suitable to
measure body temperature because it does
not have the kink in the mercury column, Figure 3.2 Measuring the temperature of a baby
as on the clinical thermometer. using a rectal thermometer
(b) The kink is intended to prevent mercury (f) Allow the thermometer to remain there
from go down quickly, allowing for a more until a 'beep' sound is heard.
accurate reading to be taken. (g) Record the temperature.
(c) Temperature readings will decrease rapidly (h) Clean the rectal thermometer using alcohol
when the laboratory thermometer is and keep it.
removed from the body and cause readings
of body temperature to be inaccurate. 4. Infrared thermometer
(a) Aim the thermometer at a distance of
about 5 cm from the individual whose
temperature is to be taken.
0 36
(b) Take the temperature reading.

-10 35
Kink
is not Kink
found



Laboratory Clinical
thermometer thermometer
Figure 3.3 How to use the infrared thermometer
Figure 3.1 Laboratory thermometer and
Clinical thermometer Interpreting Body Temperature
1. The normal human body temperature is 36.9°C.
3. Rectal thermometer
(a) Rectal thermometer is used to take accurate 2. Normal temperature estimation is between
reading of body temperature for infants 36.5°C and 37.2°C. If the temperature does
aged 3 years and below. not fall within that range, it is considered
abnormal.
(b) First, clean the bulb of thermometer using
alcohol to avoid infection. Then, rinse with
water at room temperature.



24






03 F4 Focus SC SPM.indd 24 24/02/2023 1:40 PM

Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health
3. A newborn has an unstable body temperature cause dehydration and damage the organs
because his body temperature control including the brain. If not treated properly, this
mechanism is still being developed. Senior situation will endanger lives.
citizens are also less capable of controlling the Table 3.2 Differences between fever and hyperthermia
body's temperature making their temperature
unstable. Fever Hyperthermia
Body Beyond normal Normal
4. Body temperature also varies by gender. temperature
Hormone secretion during the menstrual cycle setting point
causes female body temperature to change and
fluctuate throughout the menstruation cycle. Temperature Normal Non-functional Form
control
5. There are several factors that cause body The role of Positive Negative (Heat
temperature being higher than normal, microorganisms (infection) stroke) 4
including: and negative
(a) Infections – infections of bacteria or (inflammation
viruses will activate the body's immune not caused by
infection)
system. As a result of activation of the
immune system, a kind of biochemical Treatment Medicines such Cooling of the
as paracetamol whole body
material produced inside the body causes and aspirin
the body temperature to rise above normal.
(b) Extreme surrounding temperature –
exposure to extreme hot conditions like Checkpoint 3.1
heat stroke and extreme sunburn causing Q1 What does body temperature mean?
body temperature to rise. Q2 State four types of thermometers and their
functions.
(c) Physical stress and physical activity –
physical activity such as heavy workouts Q3 State two factors that cause body temperature
to exceed the normal temperature.
and stress increase the body's metabolic
rate, thus increasing body temperature.
6. If a person's body temperature exceeds the
normal temperature, the individual will be 3.2 Pulse Rate
suspected of having a fever.
Pulse Points on the Body
7. If a baby less than 6 months has body
temperature above normal, the baby needs to 1. Pulse rate is the measurement of the number
be taken to the hospital immediately as the of heartbeats per minute.
baby may have bacterial or viral infections.
2. Pulse point is a specific area or point where
8. Body temperature can also be less than normal. the pulse can be felt, and is counted.
This low body temperature is also called
hypothermia. Hypothermia occurs when 3. At the pulse point, the blood vessels (arteries)
the temperature of an individual is less than are close to the layer under the skin.
35°C. This condition occurs due to exposure 4. When the heart is beating, blood will be sent
to extreme cold or falling into very cold water. through the blood vessels and pressure in the
This situation can be fatal. bloodstream can be felt through the skin.
9. Temperatures can also rise up to 40°C. At 5. There are several pulse points in the body that
this temperature, an individual is said to have can be felt.
hyperthermia. The situation is different than
fever. The temperature is too high due to 6. The doctor will usually take the pulse reading
system failure of the body to regulate body at the wrist because it is clear, prominent and
temperature effectively. This condition can easy.


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Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health
7. Figure 3.4 shows the pulse points in the human body.


1
2





3

Form
4
4
5



6





7

8


Figure 3.4 The pulse points in the human body
8. Figure 3.5 shows some factors that affect the pulse rate.
Factors affecting pulse rate



Gender Age Physical Activity
Physical activity such as
Females have a higher As you get older, your heavy workout will result in
pulse rate than males pulse rate goes down higher pulse rates
Figure 3.5 Factors that affect the pulse rate

9. Athletes typically have lower pulse rates than non-athletes at rest because their cardiac muscles are
stronger.
10. Unhealthy individuals also have a higher pulse rate compared to healthy individuals.

Eksperimen 2.1
Eksperimen 2.1
Experiment 3.1
A Human pulse rate based on gender

Aim: To investigate the human pulse rate based on gender.
Problem statement: Does the human pulse rates differ according to gender?
Hypothesis: Women have a higher pulse rate than men.




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Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health
Variables:
• manipulated: Gender of students SPM Tips
• responding: Pulse rate The operational definition for pulse rate
• constant: Time period, age and physical activity in this experiment:
Pulse rate is a measurement that causes
Apparatus: Stopwatch a women’s pulse rate to be higher after 1
minute of performing the same activity.
Procedure:
1. This activity is carried out in pairs.
2. The pulse of the male student is taken in 60 seconds as shown in Figure 3.6. The stopwatch is held by the
partner to record the time. Form
3. The pulse readings are recorded three times for each individual to get an accurate reading. 4
4. Steps 2 and 3 are repeated on the female student pairs.
(Note: Make sure students are at rest.)













Figure 3.6

Result:

Gender of Pulse rate (bpm)
students Reading 1 Reading 2 Reading 3 Average

Male 78 79 80 79.0
Female 89 85 88 87.3

Discussion: Female pulse rate is higher. This is because the size of the female heart is smaller, so the female heart
has to pump blood at a higher rate than the male heart.
Conclusion: Female pulse rate is higher than that of males. The hypothesis is accepted.

B Human pulse rate based on age
Aim: To investigate the human pulse rate based on age.
Problem statement: Does the human pulse rate differ according to age?

Hypothesis: The older a person is, the lower his pulse rate.
SPM Tips
Variables:
• manipulated: Age The operational definition for pulse
• responding: Pulse rate rate in this experiment:
Pulse rate is a measurement that causes
• constant: Time period, gender and physical activity a student’s pulse rate to be higher after
Apparatus: Stopwatch 1 minute of performing the same activity.





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Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health
Procedure:
1. This activity is carried out in pairs.
2. A student's pulse is taken in 60 seconds. The stopwatch is held by the partner to record time.
3. The pulse readings are recorded three times to get an accurate reading.
4. Steps 2 and 3 are repeated for the teacher / lab assistant. (Note: Make sure the gender of the teacher / lab
assistant is the same as the student whose pulse reading is being taken and everyone is at rest.)
Result:
Age Pulse rate (bpm)
Sample
(year) Reading 1 Reading 2 Reading 3 Average
Form
Student 16 79 80 80 79.6
4
Teacher 45 78 77 78 77.6
Lab assistant 36 80 78 78 78.6

Discussion: Students’ pulse rates are higher than the teacher’s / laboratory assistant’s pulse rate. This is because
students are more active and fit.

Conclusion: The pulse rate lowers as age increases. The hypothesis is accepted.

C Human pulse rate based on physical activity
Aim: To investigate the human pulse rate based on physical activity.
Problem statement: Does the human pulse rate differ according to the type of physical activity?

Hypothesis: The more vigorous the physical activity, the higher the pulse rate.
Variables: SPM Tips
• manipulated: Physical activity
• responding: Pulse rate The operational definition for pulse rate in
• constant: Time period, gender and age this experiment:
Pulse rate is a measurement that causes the
Apparatus: Stopwatch pulse rate to increase after physical
activity such as running.
Procedure:
1. This activity is carried out in groups.
(Note: Make sure members of the group are of the same gender.)
2. One of the students in the group was asked to rest, walk and run. Each activity takes two minutes. The
student is asked to rest for 5 minutes before starting the next activity.
3. The student's pulse count is taken in 60 seconds after completing each activity and the reading is recorded
in the table.
Result:
Pulse rate (bpm)
Group Students’ name
At rest Walking Running
1 Student 1 90 91 113
2 Student 2 85 95 110

3 Student 3 90 93 111



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Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health
Discussion: When doing vigorous activities such as running, the pulse rate will increase; this is because the
amount of energy needed is increased. Therefore, the heart pumps faster, sending oxygenated blood to the body
cells.
Conclusion: The more vigorous your physical activity is, the higher your pulse rate. The hypothesis is accepted.




Checkpoint 3.2
Q1 What is the pulse rate?
Q2 Why do doctors always check the pulse on their patients' wrist? Form
Q3 Natasha and Rajesh are confused when their pulse readings are not the same. Do all individuals have pulse 4
readings that are different like fingerprints? Justify your answer.
Q4 What is a pulse reading? What is the difference between individuals with low pulse reading and individuals with
high pulse reading?



3.3 Blood Pressure 4. The best instrument based on the correct
standard for measuring blood pressure
readings is the sphygmomanometer used by
Blood Pressure Measuring Instrument hospital practitioners and clinics used with

1. Blood pressure is the pressure applied by the stethoscopes.
blood on the walls of the arteries during blood 5. However, for home monitoring, the use of a
circulation. digital sphygmomanometer is easier.
2. The instrument used to check blood pressure 6. Figure 3.7 shows an instrument used to measure
is the sphygmomanometer. blood pressure.

3. The unit for measuring blood pressure is
millimetres of mercury and the symbol is
mmHg.















Digital sphygmomanometer Analogue sphygmomanometer
Figure 3.7 Instrument used to measure blood pressure

Measuring and Recording Blood Pressure 2. The top number shows the pressure applied on
1. Blood pressure measurements are taken the wall of arteries during the contraction of the
with two measurements, the top and bottom heart muscle.
numbers. 3. This measured pressure is called systolic
pressure.



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Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health
4. The bottom number shows the pressure applied Blood pressure
on the wall of arteries during the heart muscle 120 / 80 mmHg unit
relaxation (between heartbeats). This pressure
is called diastolic.
Systolic Diastolic
5. Blood pressure measurements are recorded as pressure pressure
systolic per diastolic and measured in units
millimetres of mercury (mmHg). Figure 3.8 Blood pressure reading
Blood Pressure Reading 2. Normal blood pressure is 120/80 mmHg.
1. All individuals need to periodically check their 3. Table 3.3 below shows the classifications of
blood pressure to be aware of their health. blood pressure readings for adults.
Form
Early treatment must be done if blood pressure
4
readings are outside the normal range.

Table 3.3 Classification of blood pressure readings
Blood pressure category Systolic pressure (mmHg) Diastolic pressure (mmHg)
Optimal Less than 120 Less than 80
Normal 120 – 129 80 – 84
At risk 130 – 139 85 – 89

High blood pressure stage 1 140 – 159 90 – 99
High blood pressure stage 2 160 – 179 100 – 109
High blood pressure stage 3 180 and above 110 and above





High and prolonged blood Low and prolonged blood
pressure readings pressure readings






High blood pressure
• Does not show obvious Low blood pressure
symptoms • Dizziness and nausea
• If left unchecked, it can cause • Easy to faint and weak
heart disease and stroke



Figure 3.9 Measurement of blood pressure and its interpretation

Checkpoint 3.3
Q1 What is meant by blood pressure?
Q2 What is the tool used to measure blood pressure?
Q3 What is the normal blood pressure reading for a normal person?
Q4 How can you keep your blood pressure at a normal condition?




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Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health
Table 3.4 Body Mass Index chart
3.4 Body Mass Index (BMI) BMI (kg m ) Category
-2
<18.5 Underweight
Calculating and Determining Body Mass
Index 18.5 – 24.9 Desirable weight

1. Body Mass Index (BMI) is the measurement 25.0 – 29.9 Overweight
of body mass against height. ≥30.0 Obese

2. The Body Mass Index can be calculated using 7. Table 3.5 shows the factors that cause changes
the following formula: in body mass. Form
Table 3.5 Factors that cause increase or decrease in
body mass 4
Low body mass Excessive body mass
(a) Diseases such as (a) Consume high-calorie
3. Body Mass Index (BMI) is one way of cancer, tuberculosis diet (more than your
determining whether an individual is and metabolic body needs)
experiencing body mass problems. diseases (b) Consume sweet or oily
(b) Anorexia or bulimia snacks
4. After obtaining the BMI results, the BMI (c) Depression and stress (c) Lack of physical
chart can be used as a reference to determine (d) Side effects of taking activities such as
the individual group, whether excessive body certain drugs exercise
mass, normal or low body mass. (d) Genetics
(e) Metabolic diseases
5. Usually, BMI charts vary by gender and age. such as Cushing's
syndrome
6. Table 3.4 shows the general BMI chart. (f) Stress and poor quality
of sleep


Interpreting Body Mass Index


Excessive body mass
increases the risk of some
diseases such as heart attack,
Low body mass can increase high blood pressure, stroke,
your risk for heart problems, diabetes mellitus, joint and
causing weakness in your bone complications and so on.
immune system against
illness, fatigue, anemia,
depression and so on.







Ideal body mass can be maintained through healthy eating and
consistent physical activity, thus reducing the risk of these diseases.



Figure 3.10 Interpretation of the Body Mass Index


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Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health

Increase your body mass in a healthy way Reduce your body mass in a healthy way

• Practising a healthy and balanced diet based • Set realistic goals and mass records once a week
on the Malaysian Food Pyramid and Malaysian • Practicing a healthy and balanced diet based
Healthy Plate
on the Malaysian Food Pyramid and Malaysian
• Eat meals at a regular time Healthy Plate

• Take snacks that contain nutrients to increase • Make some changes in your diet such as changing
calories the preparation of meals
• Reduce or avoid foods that are high in sugar and
Form
• Eat more nutritious foods
fat
4
• Consult your doctor or dietitian on how to • Moderate exercise such as brisk walking and
increase your body mass in a healthy way cycling

• Get support from close people such as friends or
Malaysian
Food Pyramid family members

Fats, oils, sugars • Consult your doctor or dietitian on how to reduce
and salts your body mass in a healthy way
Meat, Fish, Eggs
Nuts, Milk
Grains Malaysian Healthy Plate
Fruits
Fruit and
Vegetables cereal products and tubers




Vegetables
Fish, poultry, meat and legumes Rice, noodle,bread, cereals,
Figure 3.11 Malaysian Food Pyramid Figure 3.12 Malaysian Healthy Plate




Checkpoint 3.4

Q1 What is the meaning of Body Mass Index?
Q2 What are the risks of diseases that you may encounter if you have a low body mass?
Q3 Complete the statement below.
Individuals who are and help individuals to achieve an ideal body
mass.




The Malaysian
Food Pyramid
2020
INFO




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Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health






CONCEPT MAP




Techniques of Measuring the Parameters of Body Health Form




4




























































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Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health

SPM Practice 3


Objective Questions

1. What is a normal body 4. Why is a laboratory C The pulse rate of an
temperature? thermometer not suitable office worker is higher
A 35.9°C for measuring body than that of a gardener
B 36.9°C temperature? D The pulse rate of an
C 37.9°C A Laboratory thermometer athlete is lower than that
Form
D 38.9°C is too long of a non-athlete
B Laboratory thermometer
4
breaks easily
2. What is the importance of C Laboratory thermometer 8. Which of the following is
normal body temperature? has no kink the unit to measure blood
pressure?
A Makes our body healthy D Laboratory thermometer A Millimetres of mercury
B Prevents us from a is difficult to operate B Metres of mercury
dangerous cancer attack C Kilometres of mercury
C Ensures that our body 5. Which of the following is a D Nanometres of mercury
functions at optimal factor that causes the body
levels temperature to rise above
D Ensures our body is not normal? 9. In blood pressure readings,
the top number shows the
injured A Eat spicy food
B Fatigue pressure applied on the walls
C Bacterial infections of the blood vessels during
3. Which of the following is the D Lack of sleep heart muscle contraction.
right step when using the What is this number?
clinical thermometer? 6. Body temperature can also A Systolic
A Make sure the be less than normal. Which B Diastolic
thermometer temperature of the following may occur if C Sistertolic
is below 35°C before use body temperature is low? D Duostalic
B Put the thermometer on A Excessive sweating
the forehead B Death 10. What is the Body Mass
C The thermometer should C Dry and bluish lips Index?
be on for about 10 D Lack of appetite A Height against mass
minutes on any part of B Body mass against
the body 7. Which of the following height
D When taking temperature statements is true about the C Weight against height
readings, make sure the pulse rate of human at rest? D Height divided by weight
thermometer is waved A Female's pulse rate is
until the temperature lower than that of a male
readings decrease B The heart rate of a
healthy person is higher
than that of a patient













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Science SPM Chapter 3 Techniques of Measuring the Parameters of Body Health
Subjective Questions

Section A
1. A student conducted an experiment to investigate the effect of heat on the temperature of a liquid. Figure 1
shows the temperature reading of the thermometer.

40 50 60 70


30 40 50 60 Form


4
Reading 1 Reading 2 Reading 3 Reading 4

35°C 72°C

Figure 1
Based on Figure 1,
(a) Complete the figure above. [2 marks]
(b) State the factor manipulated in this experiment. [1 mark]
(c) State the factor observed in this experiment. [1 mark]
(d)
When your body temperature is above 37°C, you are suspected of having a fever. Body temperature
can also be lower than normal if you are exposed to extreme cold. This condition can be fatal too!

Based on the above statement, state one factor that can cause an increase in body temperature.
[1 mark]
Section B
2. Figure 2 shows a clinical thermometer for measuring body temperature.
(a) What is the function of X? [1 mark]
(b) Why is it necessary to shake the clinical thermometer before taking body temperature
measurements? [1 mark] 36
(c) Hafiz and his wife are the parents of a two-month-old child. Their child was not feeling
well and was rushed to the clinic. Which thermometer should the doctor use to check the
temperature of their child? Explain. [2 marks] 35
(d) There are several factors that can cause body temperature to exceed normal. State two X
factors. [2 marks]

Section C
3. Study the statement below. Figure 2
The boy has a higher heart rate than his father.

(a) State one problem statement from the above information. [1 mark]
(b) Suggest one hypothesis to investigate the above statement. [1 mark]
(c) Based on the given statement, design a laboratory experiment to test your hypothesis by using a
stopwatch. Your description should include the following criteria:
(i) Aim of experiment [1 mark]
(ii) Identification of variables [2 marks]
(iii) Procedure or method [4 marks]
(iv) Tabulation of data [1 mark]



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Theme 3: Energy and Sustainability of Life Form 5
Chapter
7 Light and Optics
















































Lenses and optics are essential in physics and used in
many optical devices. Lenses refract light to create images
while optics is the study of light. These concepts enable us
to observe microscopic structures, correct vision, and see Form
distant objects. They have contributed to advancements
in medicine, astronomy, and telecommunications.
CHAPTER FOCUS What are the shapes of convex lenses and concave lenses? 5

Formation of Images by What are the differences in the image formed by a convex
lens and a concave lens?
Lenses How does a telescope function?
Optical Instruments
Besides telescopes, what are the optical instruments that
use lenses?



Access to
INFOGRAPHIC





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Science SPM Chapter 7 Light and Optics

7.1 Formation of Images by Lenses Optical centre, O
Focal point, F
Principal axis
Convex Lens and Concave Lens

1. An optical lens is made of transparent
materials such as glass or clear plastic. One or Focal length, f
both surfaces usually have a spherical curve.
Figure 7.3 Parallel rays are converged by a convex lens
2. There are two types of lenses, namely convex
lenses and concave lenses. 4. Concave lenses
(a) Concave lenses can be regarded as
being made up of numerous prisms with
different thickness.




Biconvex Planoconvex Convex meniscus
(a) Convex lens


Figure 7.4 Light rays through concave lenses

(b) When light rays pass through a concave
lens, the light rays are refracted and
appear diverge from the focal point, F.
Biconcave Planoconcave Concave meniscus
(c) Therefore, concave lenses are known as
(b) Concave lens diverging lenses.
Figure 7.1 Types of lenses
3. Convex lenses
(a) Convex lenses can be regarded as being Focal point, F
made up of numerous prisms with Optical centre, O
different thickness. Principal axis



Form
Focal length, f
5
Figure 7.5 Parallel rays diverging through a concave lens

Figure 7.2 Light rays through convex lenses 5. The focal point, F is a common point on the
principal axis where all rays close and parallel
(b) When parallel light rays pass through a to the axis converge to it after passing through
convex lens, the light rays are refracted a convex lens, or appear to diverge from it
and focused to a focal point, F. after passing through a concave lens.
(c) Hence, convex lenses are known as
converging lenses.







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Science SPM Chapter 7 Light and Optics
Activity 7.1


Aim: To show the convex lens is a converging lens and a concave lens is a diverging lens and to determine the
focal point, F of both lenses.
Apparatus: Optical Ray Kit (ray box, five slit plate, power source, a cylindrical convex lens and a cylindrical
concave lens with the same thickness), white paper, pencil, ruler
Procedure:
1. The apparatus is set up as shown in Figure 7.6.

Five slit plate
Cylindrical convex
lens






Figure 7.6 Set-up of apparatus
2. The light from the ray box is shine through five slit plate to the cylindrical convex lens.
3. The path of light that passes through the cylindrical convex lens is observed and marked on the white
paper.
4. The focal point, F of the convex lens is identified.
5. Steps 2 to 4 are repeated using the cylindrical concave lens (Figure 7.7).
Five slit plate

Ray box Cylindrical
concave lens





Figure 7.7 Set-up of apparatus
Observation:

Five slit plate Five slit plate
Ray box Cylindrical Ray box Cylindrical
convex lens concave lens Form
F 5
F
Focal
point
Discussion:
1. Convex lenses converge parallel light rays to the focal point, F.
2. Concave lenses diverge parallel light rays from the focal point, F.
3. This experiment is carried out in a dark room so that light rays before and after passing through the lens
can be seen clearly.
Conclusion:
1. A convex lens is a converging lens.
2. A concave lens is a diverging lens.




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Science SPM Chapter 7 Light and Optics
Focal Length of Convex Lens Optical centre, O
1 The focal length, f, of a convex lens is the Focal point, F
distance between the optical centre, O and the
focal point, F. Parallel rays

2 The focal length of a convex lens depends on
the thickness of the lens. f
Focal length
3 A thicker convex lens has a short focal length, Figure 7.8 Focal length of a convex lens
whereas a thinner convex lens has a long focal 4. The focal length of a convex lens can be
length. determined through activities in the laboratory.


Activity 7.2

Aim: To determine the focal length of a convex lens using distant objects.
Apparatus: Two convex lenses with different thickness, lens holder, screen, metre rule
Procedure:
Determine the
Window Focal length of
a Convex Lens
Distant Convex lens VIDEO
object
Screen


Focal length
(f )

Figure 7.9 Set-up of apparatus
1. A convex lens labelled P placed on a lens holder is directed to the object outside the window. The screen
at the back of lens is adjusted until a sharp image is formed on it.
2. The focal length, which is the length between the optical centre and the screen is measured using a ruler
and the value is recorded.
3. Steps 1 and 2 are repeated using the lenses labelled Q and R.
Result:
Lenses Thickness of lens Focal length, f (cm)
P Thinnest 30
Form
Q Medium 20
5
R Thickest 10
Discussion:
1. Parallel light rays from the distant object will focus on the focal point after passing through the convex
lens. Therefore, the focal length of lens can be determined by measuring the distance between the optical
centre and the screen.
2. From the results obtained, it is found that when the thickness of the lens increases, the focal length
decreases. This shows that a thick lens has a short focal length and vice versa.
3. Object in the laboratory cannot be used as it is too close to the lens and the light rays from near object is
not parallel.

Conclusion:
A thick convex lens has a short focal length while a thin convex lens has a long focal length.



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Science SPM Chapter 7 Light and Optics
Characteristics of Images formed by Convex Lenses and Concave Lenses
1. The characteristics of images formed by convex lenses and concave lenses can be determined by
drawing the ray diagrams. A ray diagram shows the path taken by a light ray passing through a
lens.
2. The important terms in the rays diagrams are as follows:

Focal point (F) is a point on the The axis of a lens is a straight
principal axis where the light ray Optical centre is the line that passes through the optical
travelling parallel to the principal centre of the lens. centre and at the right angle with the
axis will converge or diverge after principal axis.
passing through the lens. Optical centre
Axis
Axis of lens Parallel of lens Principal axis
Parallel light rays light rays
Focal point is a straight
line that passes
Principal axis Principal axis
O F O through the
optical centre
and it is
Focal length, f Focal perpendicular to
length, f
(a) Convex lens (a) Concave lens the axis of the
lens.
The focal length (f) is the distance between the focal point and the optical centre.


4. When drawing the ray diagrams, the following rules need to adhere.

Ray 2: parallel to the Ray 3: passing through focal
Ray 1: through optical centre
principal axis point, F
Convex lens




F F F F F F


Light ray passing through Light ray that is parallel to the Light ray passing through focal Form
optical centre is not refracted or principal axis will be refracted point, F will be refracted so that
deflected by the lens. and passes through focal point, F. it is parallel to the principal axis. 5
Concave lens





F F F F F F


Light ray passing through the Light ray that is parallel to the Light ray that travels towards the
optical centre is not refracted or principal axis will be refracted direction of focal point F will be
deflected by the lens. and looks like appearing from refracted so that it is parallel to
focal point F. the principal axis.



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Science SPM Chapter 7 Light and Optics
5. Steps to draw ray diagrams.
(a) Convex lens
Step 1
Draw a horizontal line representing the principal Principal
axis through the centre of convex lens. Mark the axis
position of focal point, F and 2F on both parts of 2F F F 2F
the lens on the principal axis.


Step 2
Draw a vertical arrow representing an object on
the left of the principal axis.
Object 2F F F 2F



Step 3
Draw the path of light from the end of object by 2
using the rules of constructing ray diagrams:
• Ray  passing through the optical centre moves 1
in a straight line without refracting.
• Ray  that is parallel to the principal axis will Object 2F F F 2F
refract to the focal point F after passing through
the lens.


Step 4 2
The intersection point of the two rays is the
position of the image formed by the convex lens. 1 Image
Draw an inverted arrow from the principal axis Object 2F F F 2F
to the intersection point to represent the image u v
formed.
u = object distance (distance between object and lens)
v = image distance (distance between image and lens)
(b) Concave lens
Form
1. Steps 1 and 2 in (a) are repeated using a concave lens.
5
2. Draw the path of light from the end of the object using the rules of constructing ray diagrams:
• Ray  passing through the optical centre moves in a straight line without refracting.
• Ray  that is parallel to the principal axis appears diverge from the focal point F at the left
of the lens after passing through the lens.
3. The intersection point of the two rays is the position of the image formed by the concave lens.
Draw a vertical arrow using dashed line from the principal axis to the intersection point to
represent the image formed.
2
1
Object 2F F Image F 2F




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Science SPM Chapter 7 Light and Optics

SPM Tips
Ray
When drawing the ray diagrams, the following matters must be given consideration: Diagram
• All rays from the objects must be drawn using solid lines and has direction.
• Rays that are not from the object (virtual ray) need to be drawn using dashed lines. Interactive
Chart
• Real images are drawn using solid lines and virtual images are drawn using dashed lines.

Table 7.1 The ray diagrams for the formation of images by convex lenses and concave lenses at different distances of objects

Distance of Ray diagram Position of image Characteristic of images
objects and their uses
Object at infinity Distant Image is formed at • Real, inverted and
object the focal point diminished
F • Used in telescopes
F
Image


u is more than Image is formed • Real, inverted and
2F between F and 2F diminished
Object F 2F • Used in single-lens
2F F camera
Image

u is the same Image is formed • Real, inverted and same
as 2F Object F 2F at 2F size as the object
2F F Image • Used in photostat
machines

u is between F Image is formed • Real, inverted and
and 2F Object F 2F further than 2F magnified
• Used in projectors
2F F Image



u is the same Image is formed at • Virtual, upright and
as F infinity magnified
Object • Used to produce light
2F F F 2F beam, example in car
headlamp and torchlight Form


u is less than 2f Image is formed • Virtual, upright and
on the object’s magnified 5
Image side • Used as magnifying glass
Object
2F F F 2F



For all values Image is formed • Virtual, upright and
of u on the object’s diminished
side • Used for spectacles

Object F Image F






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Science SPM Chapter 7 Light and Optics
SPM Tips SPM Highlights

The characteristics of the images formed by a convex
lens can be summarised as shown in the figure below. The characteristics of images formed by a convex
lens are virtual, upright, and magnified.
u = 2f u = f
Real, inverted, Virtual, upright Which of the following positions of the objects
same size and at infinity placed in front of the convex lens, will produce the
Real, Real, Virtual, characteristics?
inverted, inverted, upright,
diminished magnified magnified A B C D Convex lens
2F F
(u > 2f) (2f > u > f ) (u < f)
2F F F


• Virtual image: cannot be seen on the screen
• Real image: can be seen on the screen Examiner’s Tip
When an object is placed between F and the centre
• Virtual image formed by a lens is always upright and of lens, the image formed is virtual, upright and
on the same side of the object
magnified.
• Real image formed by a lens is always inverted and
on the opposite side of the object Answer: D



Checkpoint 7.1

Q1 What will happen when the parallel light rays pass through
(a) convex lens (b) concave lens
Q2 Complete the table below.
Optical terms Explanation
Principal axis
The middle point on the lens (centre of lens); light travels through it without refraction
Focal point, F
Distance between image and optical centre

S3 Complete the ray diagrams of the following cases:
(a) (c)
Object Object
2F F F 2F 2F F F 2F

Form
(b) (d)
Object Object
5
2F F F 2F 2F F F 2F

Q4 The figure shows three ray lights from the end of an
object towards the convex lens
(a) Complete the ray diagram. Object
(b) The three rays will meet again at a point after
passing through the convex lens. What can you
observe at that point? F F



Convex lens




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Science SPM Chapter 7 Light and Optics

7.2 Optical Instruments


Formation of the Final Image by a Telescope and Microscope
Telescope
Objective • A telescope is an optical instrument used to view distant objects.
lens
• This instrument consists of two convex lens, which are objective lens with long focal
Eyepiece length and eyepiece with short focal length.
• Objective lens forms the first image, I , that is real, inverted, diminished and located at
1
the focal point of objective lens.
• Eyepiece functions as the magnifying lens and is adjusted so that the final image which
is virtual can be formed at the infinity.
Objective lens: Eyepiece:
f o f e
Parallel light ray from
Figure 7.10 Telescope the distant object

F o
• The final image formed by F e F e
the eyepiece is virtual, upright F o
compared to first image and I
located at the infinity Light ray parallel
to the axis
• The distance between the
objective lens and the eyepiece
in the normal adjustment is
(f + f ). Parallel light ray that enters
o e the eye appears as originated
from the final image at infinity
Figure 7.11 The ray diagrams for the image formation in telescopes
Microscope


Eyepiece A microscope is an optical instrument used to observe very fine objects. A
Coarse microscope consists of two high powered convex lenses which has short focal
adjustment length.
Fine
adjustment
• Lens with the shortest focal length (f ) is used as the objective
Objective lens o
Clips lens.
Stage • Lens with the longer focal length (f ) is used as the eyepiece. Form
e
• Fine objects that are to be examined are put in between F and
Diaphragm 2F of the objective lens o
Mirror o 5
Base
Figure 7.12 Microscope
Objective Eyepiece
lens
• The function of objective lens is to produce the first image, Object
l , that is real, inverted and magnified. f o f m
1
• The objective lens is used as magnifying lens to enlarge the
image formed by the objective lens. I
• The final image (l ) formed by the eyepiece is virtual, upright I 1
2
compared to the first image, I and magnified. 2
1
• The magnifying power of the microscope is the product of
multiplication of objective lens magnification and eyepiece
magnification. Image
Magnification, M = m × m Figure 7.13 Ray diagram showing the formation of
o e
image in a microscope
m = magnification by objective lens
o
m = magnification by eyepiece
e
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Science SPM Chapter 7 Light and Optics
Designing and Building a Simple Telescope
1. The main materials required to build a simple telescope:

(a) A convex lens with the focal length f = 50 cm and large diameter as the objective lens
0
(b) A convex lens with the focal length f = 10 cm and small diameter as the eyepiece
e
(c) A cardboard tube with a diameter similar to the objective lens

(d) A cardboard tube with a diameter similar to the eyepiece


2. The objective lens and the eyepiece are arranged as shown in Figure 7.14.

f
o
f
e
Translucent
Objective Lens holder screen Image
lens Eyepiece
t = 50 cm
Eye


Retort stand Lens holder
Figure 7.14 Arrangement of the objective lens and eyepiece
3. The objective lens is directed towards a distant object.
4. A translucent screen is placed about 50 cm from the objective lens and is adjusted until a sharp image
is seen on the screen.
5. The eyepiece that is placed in front of the translucent screen is adjusted until a clear and magnified
image is seen through the eyepiece.
6. The translucent screen is removed and the set-up of the lenses can function as a simple telescope.
7. The distance between the two lenses is measured. The distance is less than or equal to the sum of the
focal lengths of the two lenses.
At normal adjustment, final image can be seen comfortably.
Distance between objective lens and eyepiece = f + f
o e
Form
5
Objective lens
10 cm
f e = 10 cm
Eyepiece f o = 50 cm
55 cm

Figure 7.15 A simple telescope
8. The objective lens and the eyepiece are then fitted into the cardboard tube as shown in Figure 7.15.
9. The structure is a simple telescope built by using a low power lens (long focal length) as the objective
lens and high power lens (short focal length) as the eyepiece.






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Science SPM Chapter 7 Light and Optics
Application of Lenses in Optical Instruments 9. The speed of the camera shutter affects the
brightness of images whether producing freeze
Camera actions or ‘blurred’ special motion effect.

Smartphone







1. A simple camera consists of a lightproof box
with a convex lens fixed in front and film at
the back of the lens.

2. The parts involved in the formation of image 1. Nowadays, all the smartphones are installed
are convex lens, focus adjustment and film. with high resolution camera to capture photos
and record videos clearly.
Shutter
Aperture
2. The camera lens consists of combination of
a few optical elements made of plastic and
Lens
Object glass. The glass optical elements can produce
Diaphragm Image
Focusing ring Film sharper and quality images.
Figure 7.16 Formation of image in the camera
Lens
3. Light need to pass through convex lens, Aperture
aperture, shutter and finally falls on the IR filter
imaging sensor.
CMOS sensor
4. A convex lens is used to formed image of Colour filter
distant objects on the film. The lens produces Figure 7.17
real, inverted and diminished image.
3. The distance between the lens and the sensor
5. Focusing ring is adjusted to make the convex is known as the focal length.
lens move forwards and backwards to focus a
sharp image on the film. 4. A thin convex lens is used in smart phones.

6. For images of distant objects, the lens The lens has short focal length and produces Form
is adjusted towards the film to get a sharp images in the angle of broad view. 5
image. For images of near objects, the lens is
adjusted further from the film to get a sharp 5. When the focal length of the lens decreases,
image. the thickness of the lens increases.

7. A diaphragm is used to change the aperture 6. The thickness of the camera lens in the smart
size in order to control the amount of light phones are a few millimeters, depends on the
entering the camera. sensor size.
8. A shutter is used to control the amount of 7. The thickness limits of smartphones are
light entering the camera. affected by the thickness of the camera lens
and the focal length of camera lens.





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Science SPM Chapter 7 Light and Optics
8. Lenses converge light from broad view angle 5. Light ray that incident onto the LCD panels
to the sensor so that the images appear are form display in their respective colours.
clear and sharp. A sensor is a part in the
camera that captures images. 6. The images from the three LCD panels are
combined by a dichroic prism and leads to the
9. The characteristics of images produced by the formation of RGB image.
camera lens in smartphones are real, inverted
and diminished.
+ + =

LCD projector (Liquid Crystal Display) Red Green Blue

Figure 7.20 RGB image
7. The light ray from the RGB image directed
onto the lens that helps to focus the image on
the screen.
8. The distance between the RGB image
produced by the dichroic prism and the lens,
1. High powered beam incident high intensity u must be f , u , 2f for the lens.
light onto the dichroic glass
9. The image produced is real, inverted and
magnified.
Light
source
Mirror Red Spectacles
Screen R dichroic
Lens LCD panel mirror

G Green
dichroic
Dichroic mirror
prism
Mirror B Blue
dichroic
mirror
Figure 7.18 1. For a person with normal vision, the thickness
of the eye lens is changed so that images of
2. The dichroic mirror only allows passing of distant and near objects are focused exactly
light with certain wavelength.
on the retina. The image produced is sharp
and clear.
Form
3. With the help of dichroic mirror, the white
rays of light are separated into red, green and 2. However, for a short-sighted or long-sighted
5
blue rays. person, light rays are not focused exactly on
the retina. Thus, the images formed on the
4. Red, green and blue rays channeled to the retina are blurred.
respective LCD panels with help of plane
mirror.

The image on
the retina is blurry

Light is focused in
front of the retina
Figure 7.19 LCD panel in a projector Short-sightedness (myopia)




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Science SPM Chapter 7 Light and Optics
The image on the 3. A magnifying glass is held so that the distance
retina is blurry of object, u is less than the focal length, f for
the lens to produce images that are virtual,
upright and magnified.
Concave lens
Light is focused at
the back of retina
Long-sightedness (hypermetropia)
Image F Object F
Figure 7.21
3. Short-sightedness can be corrected by
wearing concave lenses spectacles to diverge Figure 7.24 The formation of image by magnifying glass
light before it enters the eyes. Thus, light can
be focused exactly onto the retina. Closed circuit television (CCTV)


The image on
the retina
is clear
Concave
lens
Figure 7.22
4. Long-sightedness can be corrected by 1. The lens of a CCTV is made of glass (or
wearing convex lenses spectacles to converge plastic) to focus the light from outer to the
light before it enters the eyes. Thus, light can CCD sensor (charged-couple device) or
be focused exactly onto the retina.
CMOS sensor (complementary metal oxide
semiconductor).
The image on Optical filter
the retina
is clear
Convex Lens BNC
lens stabiliser Digital Processor Analog code
Coaxial
Figure 7.23 cable
Focal length, f
Sensor (CCD or CMOS)
Magnifying glass
Figure 7.25 Form
2. Sensor CCD gives more uniform output, 5
therefore the images produced are high quality
compared to CMOS sensor.
3. The amount of light passing through the
camera cannot be controlled by the lens.
4. Lens with adjustable ‘iris’ is only suitable for
environment with constant brightness.
1. A magnifying glass is a high powered convex
lens. 5. However, in environment with varying
brightness, auto iris lens is more suitable.
2. The device is the simplest microscope used to
produce larger size of image than the size of
object.



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Science SPM Chapter 7 Light and Optics
6. The focal length of lens measured in 13. The digital signals of images are reconverted
millimetre (mm) shows the angle of vision. to analog signal to be transmitted to coaxial
cables.
7. The short focal length (such as 3.6 mm) gives
broad angle of vision but less clear.
Checkpoint 7.2
8. The long focal length (such as 12 mm) gives Q1 In microscopes, why do objects to be observed
narrow angle of vision but can view further. need to place at position u, f , u , 2f from the
9. Lens with large angle is suitable for broad objective lens with the focal length, f?
areas such as parking space, backyard and Q2 Complete the following table by stating the
characteristics of image formed by the following
so on. Lens with narrow angle is suitable for optical instruments.
critical areas such as entrance, passage in the
hall and so on. Optical instruments Characteristics
of image
10. The images produced by CCTV lens are real, Magnifying glass
inverted and diminished. Camera
11. Digital signal processor, DSP is the ‘brain’ of Microscope
CCTV camera. Telescope
12. The processor receives analog data from the Closed circuit television
(CCTV)
sensor and converts into digital signal.
Q3 State two types of optical instruments that do not
need any electronic sensor to capture images.






CONCEPT MAP


Light and Optics










Form
5









to determine









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Science SPM Chapter 7 Light and Optics

SPM Practice 7


Objective Questions

3. Which of the following D
1. Which of the following light
ray is correct for convex diagram shows the correct Focal point
label of focal point?
lens? Parallel
A A light ray F

f
Focal point Optical centre, O Focal length
B
B 5. Figure 2 shows the set-
up of apparatus for an
investigation.
Focal point
Sharp image
C Convex
Screen lens Bulb
C
Focal point
D Distance of image, v Lens holder

Figure 2
D Focal point In the set-up of apparatus
as in the figure above, the
4. Which of the following distance of image, v is not
diagram shows the correct the focal length of the convex
measurement of focal length lens because
of convex lens? A the sharp image is
2. Figure 1 shows the light ray A inverted
passing through lens P. B a large bulb is used
Focal point C the average value of
Parallel distance of image is not
light ray F considered
Lens
P D the bulb is not a distant
object
f
Optical centre, O focal length 6. Figure 3 shows lens P is Form
thicker than lens Q. Which
Figure 1 B of the points A, B, C or D, is 5
Based on the path of light ray Focal point the focal point of lens Q?
shown in the figure above, Parallel Lens P
which is lens P? light ray F
A C
f
Optical centre, O Focal length
C
B D Focal point Lens Q
parallel
light ray F
A B C D
f
Optical centre, O Focal length
Figure 3

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Science SPM Chapter 7 Light and Optics
7. Which of the following shows 10. Which of the following is true
correctly the light ray passing about telescope? C Real, Virtual,
through the concave lens? A f , f e inverted inverted
o
B the distance between two compared compared
A Object to object, to object,
lenses . f + f e
o
O F F C the eyepiece is thinner magnified magnified
than the objective lens D Real, Virtual,
B Object D the diameter of objective inverted inverted
lens is more than the
O F F eyepiece compared compared
to object, to object,
C Object 11. What are the characteristics diminished magnified
of final image in a telescope?
O F F A Virtual, upright compared
to actual object and 14. Why is the distance between
D Object diminished RGB image formed by the
B Virtual, inverted compared LCD panels in projectors and
O F F to actual object and the screen, u is f , u , 2f ?
magnified A To form sharp image on
the screen
C Real, upright compared B To ensure the image
8. Figure 4 shows a ray to actual object and formed on screen is not
diagrams. diminished blurry
D Real, inverted compared
to actual object and C To form real image on the
magnified screen
Image D To ensure the colour of
Object F 12. For a microscope that has image formed on screen
F u f objective lens with focal is unchanged
length f , where should the
o
object be placed? 15. Which statement is correct
Figure 4 A u , f o about the formation of image
B u = f on magnifying glass?
The figure above shows the C f , u , 2f A The object should be
o
ray diagrams for D u = 2f o placed at a distance less
o
A camera o than the focal length of
B photostat machine 13. Which of the following lens
C LCD projector is correct about the B The lens needs to
D magnifying glass characteristics of image for be thin to give higher
9. A photostat machine is microscopes? enlargement
adjusted so that it can C The focal length of lens
produce the same size First Final should be long to give
of copy as the original image image higher enlargement
Form
document. The distance A Virtual, Real, D The image formed is on
between the original upright upright the opposite side of the
5
document and the convex compared compared object
lens in the machine should to object, to object,
be magnified diminished 16. Which of the following
A less than the focal length produces final image that is
of lens B Virtual, Real, virtual?
B same as the focal length upright upright A Digital camera
of lens compared compared B Smartphone camera
C twice the focal length of to object, to object, C Magnifying glass
lens magnified magnified D CCTV camera
D more than twice the focal
length of lens






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Science SPM Chapter 7 Light and Optics
Subjective Questions
Section A


1. Figure 1 shows the set-up of apparatus to observe the Sharp image
characteristics of image produced. The focal length of the Screen
convex lens is 10 cm. Convex lens Bulb
(a) State the condition in the laboratory that is suitable to
conduct the experiment. [1 mark]
(b) State the method to determine the position of the
screen to produce a sharp image. [1 mark] Image distance, v Object distance, u
(c) State the distance of object, u that is needed to Lens holder
produce a sharp image at the position of 20 cm from
the convex lens. [1 mark] Figure 1
(d) If the set-up of apparatus in Figure 1 is used to determine the focal length of the convex lens, state the
changes need to be done. [2 marks]


2. A student is investigating the images formed by convex lenses. Figure 2(a) and Figure 2(b) show the images
formed by the convex lenses when objects are placed at different position.


Object
3F 2F F F 2F
Object Image Image
3F 2F F F 2F


(a) (b)
Figure 2

(a) Based on your observation, state the hypothesis for the experiment. [1 mark]
(b) State one common characteristic of the images in Figure 2(a) and Figure 2(b). [1 mark]
(c) What will happen to the image when the object is placed at focal point F? [2 marks]
(d) Predict the position of image when the object is placed further away from the lens. [1 mark]




Section B Form

3. Figure 3 shows an optical instrument used to observe distant object such 5
as the stars. The focal length of objective lens f = 40 cm and the focal
o
length of eyepiece f = 5 cm.
e
(a) State the name of the instrument. [1 mark]
(b) Why the diameter of objective lens is larger than the eyepiece?
[1 mark]
(c) What is the function of eyepiece in the instrument? [1 mark]
(d) Calculate the enlargement produced by the instrument. [2 marks] Figure 3
(e) What will happen when the positions of objective lens and eyepiece
are exchanged? [1 mark]







355






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Science SPM Chapter 7 Light and Optics
4. Figure 4 shows a digital camera.


P

Y
Image

X Q


Figure 4
(a) On the figure,
(i) draw a suitable lens in box X. [1 mark]
(ii) state the characteristics of image produced by the lens. [2 marks]
(b) Which parts labelled P, Q, X and Y has the same function as retina in human eye? [1 mark]
(c) Based on part labelled Q,
(i) name the part labelled Q. [1 mark]
(ii) what is the function of part labelled Q? [1 mark]

5. Figure 5 shows the ray diagram for the formation of final image in an optical instrument.

Lens L 2
Object Lens L 1 First
F 1 F 2 image
F 1 F 2
Final
image



Figure 5
(a) Name the optical instrument. [1 mark]
(b) Given the focal length of lens L is f, state the suitable object distance, u in order to produce a clear
1
image. [1 mark]
(c) State one characteristic of the image formed by:
(i) Lens L
1
(ii) Lens L
2
Form
[2 marks]
5
(c) There are many types of wild birds flying far behind your house. You want to observe the birds more
clearly. Using manila cardboard, cellophane tape, eyepieces and objective lenses, create an optical
instrument to allow you to observe the birds more clearly. Sketch and label the optical instrument.
[3 marks]














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ANSWERS







Form 4 laboratory coat / Did not wear a Q2 An individual needs Heimlich
face mask Manoeuvre if found:
(b) Goggle / Face mask / Gloves / (a) holding his neck with both hands
Chapter Safety Measures in
1 Laboratory coat suddenly
the Laboratory (b) unable to talk or cough
(c) In the fume hood
(d) Not justified. Concentrated acid (c) skin, lips and nails suddenly
Checkpoint 1.1 bluish or darkens
cannot be disposed of directly Form
Q1 The school laboratory has various into the sink; only weak acids (d) difficulty breathing
chemicals that are dangerous and with a pH value of 5 or 6 can be Q3 Food that enters the breathing 4
glassware that are fragile. disposed of directly into the sink. passage will prevent oxygen from
Q2 goggles, face mask, gloves, lab coat, 3. (a) (i) Class B entering the lungs and hence cannot
be sent to the brain. Heimlich
(ii) Foam / Dry powder / Carbon
long pant and closed shoes. dioxide Manoeuvre is important to ensure
(b) (i) Dry powder victim that is choked does not
Checkpoint 1.2
(ii) ABC / Fire blanket / Carbon undergo brain damage or death.
Q1 Acid, grease, oils dioxide Q4 Can. Heimlich Manoeuvre can
Q2 Obey laboratory rules, carry out (c) be self-administered by applying
activities and experiments carefully pressure by bending the body over a
and mindfully. Rubber chair or a table and pushing the body
Q3 Sharp tools, non-sharp solids, tubing Bottle cap against the chair or table.
carcasses and body fluids
Q4 To remove any biological agents that
are dangerous on sample such as SPM Practice 2
bacteria or fungus before disposing it Mineral
into the environment. bottle Objective Questions
Mixture of baking 1. D 2. B 3. C 4. B 5. A
Q5 Inform the teacher or laboratory powder and vinegar
assistant. 6. D 7. B 8. A 9. C 10. C
Checkpoint 1.3 Subjective Questions
Chapter
Q1 Fuel, oxygen and heat 2 Emergency Help 1. (a) Perform chest compression
Q2 Water, foam, carbon dioxide and dry (b) • Victim did not respond or react
powder Checkpoint 2.1 • Victim has no pulse beat
Q3 • Not harmful to human and animals (c) Do not agree. An individual
• Do not pollute the soil Q1 CPR is an emergency help that is needs to learn proper CPR
carried out to restore heartbeat and methods from a reliable source
breathing of victims facing heart and or from a trained individual. This
SPM Practice 1 breathing problems. is because CPR methods need
Objective Questions Q2 Situations that requires CPR: to be done to save the victim’s
life without suffering other
1. B 2. D 3. A 4. D 5. D (a) not breathing injuries.
6. B 7. C 8. C 9. A 10. D (b) no pulse beat
11. B (c) do not respond to stimulus 2. (a) Heimlich Manoeuvre method
Q3 CPR is important to ensure the flow (b) Choking victim
Subjective Questions of blood throughout whole body of (c) Victim will lack oxygen causing
1. (a) Types of substances the victim. CPR is also important to brain damage and death.
(b) pH value ensure continuous supply of oxygen (d) Chair or table
(c) Acid is a substance that to the victim’s brain to avoid brain (e) Bring victim to hospital for further
produces a pH value of 2 to 6 damage. treatment.
when tested with a pH meter.
(d) Black coffee, cow’s milk Checkpoint 2.2 Chapter Techniques of Measuring the
3
Q1 Heimlich Manoeuvre is an emergency Parameters of Body Health
2. (a) Do not use personal protective procedure that is carried out to save
equipment / Did not conduct an an individual who is choking, due to Checkpoint 3.1
experiment in the correct station something (for example food) being
/ Did not wear goggles / Did stuck in the trachea. Q1 Body temperature is the degree of
not wear gloves / Did not wear hotness and coldness of body.




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Science SPM Answers
Q2
SPM Practice 3 Chapter Green Technology for
4
Type of Environmental Sustainability
thermometers Function Objective Questions
Clinical Used to measure body 1. B 2. C 3. A 4. C 5. C Checkpoint 4.1
thermometer temperature 6. B 7. D 8. A 9. A 10. B
Q1 Green technology is the development
Laboratory Used to measure Subjective Questions and application of products,
thermometer temperature of liquids 1. (a) 44°C equipment and systems used
Rectal Used to measure body 54°C conserve the environment and
thermometer temperature of babies (b) Effect of heat / Quantity of heat nature, as well as minimising and
through their anus (c) Temperature reducing the negative effects of
Infrared Used to measure body (d) Infection / Extreme surrounding human activities.
thermometer temperature without temperature / Physical stress Q2 (a) energy conservation can be
having any contact with and physical activity increased
Form
the body (b) the county’s economy will be
2. (a) Prevent the mercury from strengthened
4
Q3 Bacterial infection and exposure to dropping fast / Allow a more Q3 Energy sector, waste and wastewater
extreme heat. accurate reading to be recorded management sector, agriculture and
Checkpoint 3.2 (b) To ensure that the temperature forestry sector, transportation sector
is below 35°C before being
Q1 Pulse rate is the measure of number used. Checkpoint 4.2
of heart beats per minute. (c) Rectal thermometer. To obtain
Q2 Wrist is where the pulse beat is clear, an accurate reading for the baby. Q1 (a) Increase in the use of fossil fuels

(b) Extreme climate change
exposed and easy.
(d) Infection / Extreme surrounding (c) Production of greenhouse gases
Q3 No. Pulse rate is not like finger prints. temperature / Physical stress which cause global warming
Pulse rate of everyone may be the and physical activity Q2 Hydro and solar energy. Malaysia is a
same or different based on factors tropical country with plenty of natural
like gender, age and physical activity. 3. (a) Does the human pulse rate differ water reserves. Apart from that,
A finger print of everyone differs since according to age? Malaysia is situated at the equator
birth. (b) The older a person is, the lower and receives enough sunshine the
Q4 Pulse beat is the pressure felt when his pulse rate. whole year round.
blood is pumped by the heart and (c) (i) To investigate the human Q3 Geothermal energy has many
flow through blood vessel near the pulse rate based on age. limitations and depends on
surface of the skin. Pulse rate differs (ii) Manipulated: Age several factors especially suitable
according to factors like gender, age Responding: Pulse rate geographical factor.
and physical activity. Constant: Time period,
Gender: Females have higher pulse gender and physical activity Checkpoint 4.3
rate than males. (iii) Procedure:
Age: Pulse rate decrease with aging. 1. This activity is carried out Q1 (a) Sewage and rubbish disposed
Physical activity: Vigorous activity in pairs. of into the river pollute our water
increases the pulse rate. 2. A student’s pulse is source and threaten aquatic life.
taken in 60 seconds. (b) Generation, management and
Checkpoint 3.3 The stopwatch is held by breakdown of solid wastes
Q1 Blood pressure is the pressure applied the partner to record the contribute towards the production
of greenhouse gases.
by the blood on the artery during blood time.
circulation when blood is pumped by 3. The pulse readings are Q2 (a) Application of 5R
heart to the rest of the body. recorded three times to (b) Carry out treatment and
get an accurate reading.
Q2 Sphygmomanometer 4. Steps 2 and 3 are processing of solid wastes.
Q3 120/80 mmHg repeated for the teacher / Checkpoint 4.4
Q4 • Practise a healthy lifestyle, a lab assistant. (Make sure
balanced diet and do exercises. the gender of the teacher Q1 Excessive use of chemical fertilisers
• Frequently monitor at home using a / lab assistant is the will affect the pH of soil and causes
digital sphygmomanometer. same as the student.) it to be unsuitable for agriculture.
(iv) Tabulation: Excess chemical fertilisers will enter
Checkpoint 3.4 the rivers and pollute the water
Pulse rate (bpm) source.
Q1 Body Mass Index (BMI) is the Age (year)
measurement of body mass against 1 2 3 Average Q2 (a) Control logging activities by
height. gazetting more areas as reserve
Q2 Reduce body mass can increase 16 forest.
risks of heart problem, body immunity, (b) Replanting of trees
anaemia, depression and others. 30
Q3 Practise healthy eating, do consistent Checkpoint 4.5
physical activity (accept other suitable Q1 Greenhouse effect and formation of
answers) acid rain


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Science SPM Answers
Q2 (a) Green transportation is introduced Smoke emitted from motor recombinant DNA technology, gene
to minimise the release of vehicles contains carbon dioxide therapy
greenhouse gases and carbon monoxide. Q2 Recombinant DNA technology
(b) Invention of natural gas for These gases are greenhouse
vehicles which does not use gases and can cause global Q3 Genetically modified food contain
petroleum as fuels. warming. higher nutritional value and a higher
Acid rain affects the corrosion of resistance against pests.
Checkpoint 4.6 the structure, causing the metal Q4 Genetic engineering can help identify
to rust. genetic disorders at an early stage.
Q1 (a) Practise recycling by separating However, one disadvantage is that
your rubbish. genetically modified food may carry
(b) Save electricity by switching off Chapter Genetics side effects such as causing allergic
5
electrical appliances that are not reactions in individuals.
in use. Form
Checkpoint 5.1 Checkpoint 5.5
SPM Practice 4 Q1 DNA is a double helix made up from Q1 Variation is the differences in
a series of genes which are the individuals of the same species. 4
Objective Questions genectic codes that determine the Q2 In continuous variation, the
1. A 2. A 3. B 4. A 5. D physical traits of an individual. differences in individuals of the same
6. D 7. A 8. B 9. B 10. C Q2 (a) Mitosis is a process where a species is not discretely apparent,
Subjective Questions parent cell divides into two for example human height. In
identical daughter cells.
1. (a) Agriculture and forestry sector (b) Meiosis is a process where discontinuous variation, variations
(b) • Land cleared for settlement a parent cell divides into four come in distinct and discrete classes
or groups, for example blood groups.
and agriculture cells with only half the genetic
• Logging for furniture and paper information the parent cell carries. Q3 There are two factors that cause
industry Q3 Crossing over variation, which are genetic factors
(c) • Replanting of trees Q4 Mitosis produces two diploid daughter (crossing over, independent
• Treatment of agricultural waste cells whereas meiosis produces two assortment of chromosomes,
to produce compost haploid daughter cells. (Accept any random fertilisation and mutation)
• Enforcement and control of suitable answers) and environmental factors (nutrients,
logging activity Q5 Mitosis is important for cell growth. temperature, light and pH).
2. (a) X – Service vehicles Meiosis is important for producing Q4 • Variations are important for survival
of the species through camouflage
Y – Public transportation gametes for reproduction. to protect themselves from
Z – Bicycle predators.
(b) • Production of greenhouse Checkpoint 5.2 • Variation is also important to help a
gases can be reduced, social Q1 The phenotype refers to the physical species adapt to drastic changes in
health improved, saving of traits of an organism. the environment.
energy sources can be well
implemented. Q2 1 rounded seed plant : 1 wrinkled SPM Practice 5
(c) • Carbon content in air seed plant
increases, greenhouse effect Q3 The father Objective Questions
worsens, global warming felt 1. C 2. C 3. C 4. D 5. A
and extreme climate change Checkpoint 5.3 6. B 7. A 8. B 9. C 10. A
3. (a) W – focus on the effort to Q1 Mutation can be divided into 11. D
minimise disposal of solid and chromosome mutation (Down
liquid waste to the environment. syndrome, Turner syndrome, Subjective Questions
Y – energy sector Klinefelter syndrome) and gene 1. (a)
(b) Energy. Green technology mutation (colour blindness, sickle cell Blood group A B AB O
promotes energy efficiency and anaemia, thalassemia, haemophilia
finds alternatives so as not to be and albinism). Number of 14 5 9 7
dependent on energy. Q2 Factors that may cause mutation residents
(c) Domestic wastes collected (any 3): spontaneous, chemical toxic, (b)
can be processed to compost. ultraviolet ray, X-rays, radioactive
Compost as fertiliser is safer rays, late pregnancy Number of residents
to use compared to chemical
fertilisers that are commonly Q3 One application for genetic research 16
used. is in the field of gene therapy. 14
Domestic wastes can be Gene therapy can be used to fix 12
processed and used as a mutated, damaged or abnormal
biomass fuel source. genes. Through gene therapy, normal 10
Biological energy sources are a genes can be inserted into the cell 8
type of renewable energy that or patient’s body tissue to replace 6
have the potential to replace damaged genes.
fossil fuels. 4
(d) Increased use of motor vehicles Checkpoint 5.4 2
led to an increase in petroleum Q1 genetically modified organisms, 0 Blood
demand. A B AB O group


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Science SPM Answers
(c) Discontinuous variation Has a body size Has a body size 6
2. (a) (i) Female similar to the much larger than SPM Practice
(ii) The offspring has two X endoskeleton the endoskeleton Objective Questions
chromosomes 1. D 2. A 3. B 4. B 5. D
(b) Male Q3 The human skeletal system consists 6. B 7. C 8. D 9. C 10. D
of 206 fused bones. The skeleton can
(c) 50% be divided into two parts, which are
(d) Number of chromosomes: 44 + appendicular skeleton and the axial Subjective Questions
XO skeleton. The axial skeleton is made 1. (a) (i) Reading on the ruler:
Disorder: Turner syndrome up of the skull, vertebral column, 2.5 cm, 3.8 cm, 6.2 cm
3. (a) (i) Continuous variation rib cage and sternum whereas the (ii) The plant absorbs nutrients
from the ground.
(ii) Genetic factor appendicular skeleton consists of the (b) (i) The growth rate of boys is
(b) Skin colour is influenced pectoral girdle, pelvic girdle, upper higher than of girls.
by both genetic factors and limbs and lower limbs. (ii) The growth rate of girls is
environmental factors. Although Q4 Centre of gravity and base area higher than of boys.
Form
Ahmad inherited his light skin Q5 Kangaroos use their tail as the
4
colour from both parents, being support system to increase the base 2. (a) X: Biceps
exposed to the hot sunny area when it is in standing position. Y: Tendon
weather for long periods of time (b) Strong and inelastic
causes his skin colour to darken Checkpoint 6.2 (c) When the biceps muscle
naturally. contracts, the triceps relaxes.
(c) • Variation allows a species to Q1 When the biceps contract and the The pull force is transferred via
adapt to drastic changes to the triceps relax at the same time, the the tendon. The radius bone is
surroundings. forearm is pulled up and the arm is pulled upwards.
bent.
• Variation enables us to easily Q2 • Taking a diet that is full of calcium, 3. (a) Aerenchyma tissue
differentiate and recognise phosphorus, vitamins, proteins and (b) Aquatic plants are supported
each individual in the same iron. by water buoyancy. There is air
species. • Adopting a good posture. space / air sac in the stem / leaf
4. (a) (i) Meiosis I Q3 The definition of growth is a tissue to make it float.
(ii) S, Q, T, R consistent and irreversible change (c) Lotus / Duckweeds
(b) The chromosomes condense, to shape, increase in mass and size (d) Agree, aquatic plants will float
or sink in the water in the
shorten and become visible. of an organism throughout its growth aquarium.
Chromosomes exchanged process.
genetic information through a
process known as crossing over. Q4 The human growth pattern is a Chapter
sigmoid shape. Growth rates are
(c) When a sperm which is highest at the infancy stage, then 7 Body Coordination
haploid (carrying half of the slowing down at the childhood stage.
chromosomes in the parent The growth rate will accelerate again
cell) fertilises an ovum which is at the adolescence stage then reduce Checkpoint 7.1
also haploid, a diploid zygote is again at adulthood. Finally, growth Q1 Hormones are organic chemicals
produced. rates turn negative in the old age substances secreted by endocrine
stage. glands directly into the blood
Chapter Support, Movement and Q5 Teenage girls have higher growth circulatory system.
6 Q2 (a) Estrogen
Growth rates than boys because they reach (b) Adrenaline
puberty earlier than boys. (c) Thyroxine
Checkpoint 6.1 Q3 (a) Lack: simple goiter;
Q1 Three types of animal skeleton: Checkpoint 6.3 Excessive: toxic goiter
(a) Endoskeleton (example: cow) Q1 The importance of support system in (b) Lack: dwarfism;
(b) Exoskeleton (example: prawn) plants: Excessive: gigantism
(c) Hydrostatic skeleton (example: (a) Twigs and leaves are positioned (c) Lack: diabetes insipidus:
earthworm) for maximum exposure to Excessive: headaches
sunlight.
Q2 Checkpoint 7.2
(b) Flowers are positioned for
Terrestrial Aquatic pollination. Q1 (a) Tranquilisers will prevent or
vertebrate vertebrate (c) Seeds are placed strategically for slow down nerve impulse
seed dispersion. transmissions in body
Similarity: coordination. The user will feel
Has an endoskeleton Q2 Floating aquatic plants have large tired and at ease. Tranquiliser
air sacs in roots and leaves to keep
Larger and Small and weaker the structure afloat. Aerenchyma includes morphine and opium.
stronger pelvic and pelvic and pectoral tissue keep the plant floating and is (b) Stimulants will speed up impulse
pectoral girdle girdle essential in gaseous exchange. transmission in body coordination.
Body weight Majority of the Q3 By counting the number of growth The user will feel active, anxious
supported by the weight supported rings in the trunk of woody plants. and paranoid. Stimulants include
endoskeleton by water buoyancy nicotine and caffeine.



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06 Ans Focus SC SPM.indd 398 24/02/2023 3:33 PM

Science SPM Answers
Q2 Hormonal imbalance - the body (ii) Pituitary gland / Thyroid Hallucinogen Change the nerve
experiences physical and mental gland / Pancreas / Ovary / impulse transmission
changes such as a larger body, Testes pathways in the brain
depression, poor memory (Any one)
Slurred speech - the cerebrum which (d) 1. Sedative drugs slow down (Any two)
is where the area in charge of speech the movement of impulses
is located, is affected in body coordination but (c) (i) Body coordination
Q3 Cirrhosis of the heart - scarring stimulant drug speed up the Slow reflexes
transmission of impulses
and hardening in the liver due to 2. Sedative drug users will be Drug and alcohol abuse
excessive consumption of alcohol sleepy and less anxious but can slow down the nerve
and drugs stimulant drug users will be system’s response towards
stimuli. Chemicals will collect
Stomach ulcer - sores in the stomach very confident and alert to between the afferent neurone
membrane because of excessive the surrounding changes. and interneurone blocking Form
excretion of acid when alcohol is 3. (a) Drugs are chemicals that affect the transmission of impulses.
consumed the neurones by slowing down Loss of balance
impulse transmissions between Consuming drugs and 4
Checkpoint 7.3
neurones. alcohol can lead to weak
Q1 The mind is the brain function that (b) Drug category: muscle coordination and the
relates to our consciousness, such • tranquiliser - Barbiturate, inability to walk properly.
as personality, thinking, memory, heroine, morphine (ii) Physical and mental health
judgement, intellect and emotion. • Inhalant - Glue, gasoline, ether Liver cirrhosis
Q2 Features of a healthy mind: Can • stimulants - amphetamine, Alcohol abuse can lead to
think and make judgement, able caffeine, nicotine toxic effects to the liver.
to detect stimuli, can recall past • hallucinogen - marijuana, Cirrhosis of the liver is a
events, dare to accept challenges, Lysergic asid diethylamide serious condition where the
able to differentiate between rights (LSD) (choose any two) liver experiences chronic
from wrong, responsible, free from (c) Effects of drug abuse: damage, scarring, hardening
prejudice, leads a peaceful life, open- • Hormonal imbalance and impaired liver functions.
minded, able to reason • Slurred speech Hallucinations
Q3 Drug abuse, alcohol abuse, mental • Slow reflexes Consuming drugs like

(or any other acceptable
stress answers) inhalants and hallucinogens
4. (a) (i) Oestrogen will affect the brain and
SPM Practice 7 (ii) - Stimulates the development change perceptions.
of secondary sex (d) • A healthy mind refers to the
Objective Questions characteristics brain’s ability to think and
1. C 2. A 3. B 4. C 5. B - Stimulates the formation of reason logically.
6. C 7. D 8. D 9. A 10. B ova • Person with a healthy mind
11. B 12. B (b) During teenager (puberty) learn to accept criticism well
and is able to become a role
Subjective Questions (c) (i) Testes model in the family.
1. (a) Pancreatic glands are important (ii) Testosterone • He is able to develop good
to control blood glucose 5. (a) Drugs are chemicals that enter relationships in the workplace
concentration. the body and disrupt the function and produce quality work.
(b) (i) Removal of the gland of neurons in the nervous • He practices a healthy lifestyle
system by slowing down the
(ii) Concentration of glucose in movement of nerve impulses in and can help to generate the
the blood neurons. economy of the country.
(iii) Size of mouse
(b)
(c) The pancreatic gland excretes Chapter
insulin which controls the Type of Action 8 Elements and Substances
concentration of glucose in drug
blood, preventing diabetes
mellitus. Tranquiliser Stops or slows Checkpoint 8.1
2. (a) Adrenal gland down nerve impulse Q1 (a) high melting point
transmissions in body
(b) Prepares the body to act during coordination (b) positive ion or cation
an emergency / Increases the Q2 Atom, molecule and ion
heart rate / Increases the rate of Stimulant Speeds up impulse
metabolism / Increases the rate transmission in body Q3 Iron can exist as atom or ion. Iron
of blood glucose / Increases the coordination atoms exist in a new iron hammer.
size of the pupil When the iron hammer starts rusting,
(Any one) Inhalants Chemicals that can iron exist in the form of ions.
(c) (i) Endocrine gland is a be inhaled through Checkpoint 8.2
ductless gland that secretes breathing can cause
hormones directly into the hallucinations Q1 Elements are arranged horizontally
bloodstream. according to their increasing proton
number from left to right.


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Science SPM Answers
Q2 (b) (i) Atom Q3 • Superconductor alloy is used in
(ii) Molecule making high-powered railway
Proton Electron
Element (c) tracks.
number arrangement • Superconductor alloy is also used
in Magnetic Resonance Imaging
W 15 2.8.5 (MRI) machine.
X 16 2.8.6
Checkpoint 9.2
Y 17 2.8.7 Q1 Transparent, chemically inert and
(d) Rust / Iron oxide easy to shape (accept other suitable
Z 18 2.8.8
(e) Sodium ion / Chloride ion answers)
Q3 Electron arrangement P: 2.7 2. (a) Arranged in ascending order of Q2 Aluminium silicate
Q4 Metal atoms will form positive ions by proton numbers. Q3 (a) Fused silica glass is transparent
donating electrons, while non-metal (b) (i) S and can withstand high heat and
Form
atoms will form negative ions by (ii) U suitable for making lenses and
accepting electrons. (iii) 9 spectacles. Lead crystal glass
4
(c) Neon gas / Gas R. When has a high reflective index and
Checkpoint 8.3 electricity is passed through shiny suitable for making prism
Q1 Isotopes are atoms of an element neon, it emits coloured light. and decorative items.
Neon gas is also an inert gas,
with same number of protons but which does not react with other (b) Ceramic is a good insulator of
different number of neutrons. For chemicals, so it is more effective. heat and suitable for making
example, there are two types of the lining in furnace. The inert
carbon atoms in a sample of carbon 3. (a) 19 property of ceramic towards
element, that is carbon atom with 6 (b) Q chemicals and resistant towards
protons and 6 neutrons and carbon (c) 2.6 corrosion made it suitable as
atom with 6 protons but 8 neutrons. (d) Atom Q needs to donate one kitchenware.
So, carbon has isotopes. electron to achieve octet electron Q4 Glass can be melted for recycling.
arrangement.
Q2 (e) Ceramic will harden when heated to
high temperatures. Hence, ceramic
Isotope Bromine-79 Bromine-81 cannot be recycled.
Electron
Number of Checkpoint 9.3
protons 35 35 Proton Q1 Natural polymers exist in living things
in nature
Number of 35 35 Neutron
electrons Synthetic polymers are man-made
through chemical processes
Number of 44 46 Q2 Sulphur atoms forms cross-links
neutrons 4. (a) (i) Proton and neutron between rubber molecules to form
(ii) Nucleon number is the total vulcanised rubber.
Nucleon 79 81 number of protons and
number neutrons in the atom.
(iii) 1 electron
Q3 Isotopes of an element have the same
number of protons. (b) (i) 17
So, number of protons in an atom of (ii) Atom L and atom J have the
phosphorus-31 = 31 – 16 = 15 same number of electrons in
So, the number of neutrons present their outermost shell.
in an atom of phosphorus-32
= 32 – 15 = 17 Chapter Chemicals in Industry Cross-links
9
Q4 In medicine, isotope cobalt-60 is used Q3 Polymerisation is the process of
to kill cancer cells. Apart from that joining the monomers through the
isotope sodium-24 is used to detect Checkpoint 9.1 formation of chemical bonds to
the location of blood clot. Isotope Q1 Duralumin produce a long chain polymer.
iodine-131 is used to treat thyroid Depolymerisation is the process of
gland. Q2 (a) Iron and carbon splitting a long chain polymer into
(b) Addition of carbon element in iron its monomers through chemical
SPM Practice 8 during alloying process disrupts reactions.
the orderly arrangement of atoms
Objective Questions in iron. This is because the size SPM Practice 9
1. A 2. C 3. A 4. C 5. B of carbon atoms is different from
6. D 7. A 8. C 9. B 10. B iron atoms. Presence of carbon Objective Questions
11. D 12. D 13. C atoms make it difficult for the 1. A 2. C 3. A 4. D 5. B
layers of iron atoms to slide when 6. D 7. A 8. D 9. B 10. B
Subjective Questions a force is applied. 11. C 12. D
1. (a) Atom, ion, molecule



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Science SPM Answers
Subjective Questions 2. Antibiotics: Penicillin, 2. (a) Traditional medicines are
1. (a) (i) Types of metal blocks streptomycin derived from plants and animals.
(ii) Diameter of the dent 3. Psychotherapeutic: Modern medicines are made by
(iii) Mass of the weight Antidepressant, stimulants scientists in the laboratory based
on the active ingredient in the
(b) Bronze is harder than copper. Q2 Complementary methods are natural natural substances.
/ Alloy is harder than its pure methods and ensure that the patient (b)
metal. is holistically, physically, mentally
(c) Bronze is harder than copper. and emotionally healthy. This method Traditional
2. (a) (i) Y: Copper does not involve the use of medicines medicine Function
or surgery.
Z: Zinc
(b) Alloying Q3 Effects include patient not recovering, Tongkat Lowers body temperature
addiction problem and problem with
(c) (i) Hard resistant bacteria. Ali of patient with high fevers
(ii) Addition of zinc atoms Aloe vera Heal skin wounds / reduce Form
prevent the layers of copper Checkpoint 10.2 swelling
atoms from sliding over each 4
other easily. Thus, alloy is Q1 Free radicals are atoms or molecules
harder. that lack one electron which makes Chapter Force and Motion
11
3. (a) Is alloy harder than pure metal? the atoms or molecules unstable,
reactive and tend to attack other
(b) Alloy is harder than pure metal. atoms or molecules.
(c) (i) Comparing the hardness of Checkpoint 11.1
alloys and pure metals. Q2 Effects include cancer, cardiovascular
(ii) Manipulated variable: Types diseases, internal organ failure and Q1 Distance is the total path length
of materials used premature aging. travelled by an object, whereas
Responding variable: Checkpoint 10.3 displacement is the distance of the
Diameter of the dent shortest path that connects two
Constant variable: Height of Q1 Antioxidants are chemical compounds locations in a specified direction.
the weight released that are needed by the body to Displacements
(iii) 1. Set up the apparatus as slow down or to stop the oxidation Q2 Velocity = Time
shown in the figure. process. 100 m
Retort stand Q2 Antioxidants stabilises the free = 9.58 seconds
radicals by providing them the
missing electron and help stop the = 10.44 m s -1
9
8 chain reaction from forming free
7 Q3 Acceleration = Changing in velocity
6 radicals. Time taken
Metre 5
rule 4 Q3 Oxidation of food takes place when (8 m s – 0 m s )
-1
-1
3 =
2 Weight food is exposed to air. 10 s
1
0 -2
Checkpoint 10.4 = 0.8 m s
Steel Q1 Active ingredients are active chemical Checkpoint 11.2
ball compounds that have effects on
Copper block the body system in diagnosis, cure, Q1 (a) velocity
2. Drop the weight from a treatment or prevention of disease. (b) acceleration
height of 30 cm. Q2 Many people take health products to Q2 In the velocity-time graph,
3. Measure the diameter of maintain their health. An increasingly displacement is obtained by
the dent formed on the hectic lifestyle and lack of a balanced calculating the area under the graph.
copper block. diet caused certain people need
4. Repeat steps 1 to 3 using health products to guarantee health. Checkpoint 11.3
a brass block to replace Q1 Acceleration due to gravity is the
the copper block. SPM Practice 10 acceleration that occurs in the Earth’s
5. Record the observations gravitational field.
in the table. Objective Questions Q2 Object in free fall means object is
(iv) 1. D 2. C 3. A 4. C 5. A falling with only gravitational force
Diameter of the 6. D 7. D 8. B 9. C 10. C acting on it.
Types of block
dent (mm) Subjective Questions Q3 (a) False
Copper block 1. (a) (i) Aspirin (b) False
Brass block (ii) To kill or to prevent Checkpoint 11.4
reproduction of bacteria
(iii) To treat psychiatric patients Q1 Inertia is defined as the tendency
Chapter Chemicals in Medicine (b) (i) Aspirin of an object to maintain its state,
10 and Health (ii) Not suitable. Aspirin is acidic whether at rest or in motion with
and can cause internal uniform velocity. We also define
inertia as the resistance of an object
Checkpoint 10.1 haemorrhage // swollen to change in its state of rest or
Q1 1. Analgesics: Aspirin, paracetamol pancreas // liver failure // skin motion with uniform velocity.
rashes for children.
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06 Ans Focus SC SPM.indd 401 24/02/2023 3:33 PM

Science SPM Answers
Q2 – When a car in motion suddenly 3. (a) The toy car moves with uniform • To kill cancer cells
stops, all the passengers are velocity because the distances • To detect leakage from
thrown forward. between any two consecutive underground pipes
– When the lift starts to descend, we dots on the tape are the same. Q2 Nuclear energy is an electrical energy
seem to be left hanging in space. (b) (i) Time between two dots source that is cleaner and more
Q3 The larger the mass of an object, the = 1 ÷ 50 s = 0.02 s efficient because coal and natural
greater its inertia. Time taken to move from M gas will cause wastage and pollution
during the combustion process.
to N Q3 • Harmful to health of the residence
SPM Practice 11 = 0.02 s x 5 = 0.1 s in the long term.
(ii) Velocity of toy car • Risk of nuclear accident when
Objective Questions -2 reactor is in operation.

= 10 cm ÷ 0.1 s = 100 m s
1. B 2. B 3. D 4. B 5. D (c) Zero (no acceleration)
6. C 7. A 8. B 9. A 10. C Checkpoint 12.2
11. C (d) Q1 Nuclear fission and nuclear fusion
Form
Direction of motion
Subjective Questions 4. (a) Does the mass of an object Q2 Nuclear fission
4
1. (a) Rate of change of velocity affect the inertia of the object? Q3 • Lack of energy sources
(b) u = 4.5 (b) The larger the mass of an • Very high energy demand
(5 x 0.02)
object, the greater the inertia of
= 45 cm s -1 the object. Checkpoint 12.3
22.5 (c) (i) To study the relationship Q1 Two Japanese cities (Hiroshima and
v = between mass and inertia
(5 x 0.02) Nagasaki) destroyed, many civilians
(ii) Manipulated variable: Mass killed. Buildings collapsed and
= 225 cm s -1 of plasticine burned.
v – u Responding variable: Period
a = T of oscillation Q2 • Destroys marine ecosystem
225 – 45 Constant variable: Length of • Land is polluted and unsafe for
= habitation
2 x 0.1 oscillating hacksaw blade
= 900 cm s (iii) 1. Attach a piece of Q3 Exposure to radioactive radiation will
-2
cause humans to suffer from somatic
= 9.0 m s -2 plasticine of mass 30 g and genetic effects. Somatic effects
to the free end of the
(c) Air resistance and friction hacksaw blade. include fatigue, cataract and hair loss.
between ticker tape and ticker 2. Slightly displaced Genetic effects include deformed
timer. sideways the hacksaw offspring, cell mutation and cancer.
2. (a) Velocity is defined as the rate blade and release it.
of change of displacement for a 3. Record the time Checkpoint 12.4
taken for 10 complete
motion. oscillations using a Q1 • Dwindling reserves of fossil fuels
(b) The car experiences stopwatch and record in encourage the construction of
deceleration/negative a table. nuclear power plants.
acceleration. 4. Repeat steps 1 to 3 • Nuclear power plants do not
(c) using 40 g, 50 g, 60 g produce air pollutants, therefore air
pollution and greenhouse effect will
Velocity (m s ) and 70 g of plasticine. not occur.
–1
(iv) Q2 • Nuclear power plants produce
radioactive waste that is harmful
Mass of Time for 10 Period, to the environment and living
plasticine oscillations, organisms.
(g) t (s) T • Cost of constructing nuclear power
30 plants and managing radioactive
waste is very high.
40 Q3 Student’s answer
Time (s) 50 SPM Practice 12
60
(d) Acceleration Objective Questions
= Changing in velocity 70 1. C 2. C 3. D 4. A 5. D
Time taken 6. C 7. C 8. A 9. C 10. C
Final velocity(v) – Initial velocity (u) Subjective Questions
= Chapter
Time taken (t) 12 Nuclear Energy 1. (a) X - uranium fuel rods
(0 m s – 20 m s ) (b) Release heat energy through
-1
-1
=
5 s Checkpoint 12.1 nuclear fission to heat up gas
= -20 m s -1 flowing through reactor
5 s Q1 • To kill bacteria for the purpose of (c) • Concrete shield
= -4 m s -2 sterilising medical equipment • Boron control rods
402





06 Ans Focus SC SPM.indd 402 24/02/2023 3:33 PM

Science SPM Answers
(d) • Land polluted by radiation and • A nuclear power station is such as algae and some protozoa
unsafe for habitation capable of generating large grow well in dark places.
• Cause somatic and genetic amounts of electricity, as Photosynthetic microorganisms
effects on humans well as capable of supplying grow well in the presence of light.
2. (a) The process of combining two electricity to more settlement Q6 The low pH of acetic acid in vinegar
light radioactive nuclei to form a areas is not conducive for the growth of
heavier nucleus with the release • Nuclear power stations do microorganisms.
of energy not produce air pollutants Q7 • To dry the clothes
(b) Similarity - Both produce huge compared to thermal power • Ultraviolet rays from the Sun will kill
amounts of energy. stations. The quantity of microorganisms.
Difference - Nuclear fission greenhouse gases in the air
produces two new nuclei that are can be reduced. Acid rain Checkpoint 1.2
lighter and more stable; nuclear production can be reduced Q1 • Break down indigested food in the
fusion produces a heavier and I do not support large intestine
more stable atom. • Energy saving practices is • Produce vitamins B and K which
(c) Generate electricity needed to reduce daily energy can be absorbed by the human
consumption. This method
(d) • Destroy marine ecosystem is able to reduce thermal body
• Propagation of radioactive pollution caused by heat Q2 (a) Secretes cellulase enzymes to
radiation to environment and release. break down cellulose in plants
living organisms • The use of other alternative into simple sugars
3. (a) Nuclear fission energy sources such as solar (b) Secretes enzymes to break down
(b) Nuclear energy and hydroelectric energy is cellulose in wood into sugars
(c) Fission process is allowed to safer and significantly less Q3 (a) Yeast (c) Bacteria
occur continuously at a uniform pollution. (b) Bacteria
rate under controlled conditions. • The cost of building a nuclear
Nuclear energy released is used power station is very high Q4 • Production of antibiotics using
to heat up water to become in addition to the cost of bacteria and fungi. Penicillin is
steam. Steam is used to rotate maintenance and safety which an antibiotic produced by fungi
the turbine of the electric is much more expensive. while streptomycin is an antibiotic
generator. Indirectly threaten the country’s produced by bacteria.
economy.
(d) Produce radioisotope materials • Dangerous radioactive waste • Dead or weakened microorganisms
such as bacteria can be used to
4. (a) Nuclear fission and have a long shelf life can produce vaccines. A vaccine is
(b) (i) Boil water to produce steam pollute the environment and given to an individual to stimulate
(ii) Rotate turbine have a negative impact on the body to produce antibodies to
(iii) Generate electricity humans. fight against diseases.
(c) (i) Neutron Form 5 Checkpoint 1.3
(ii) Uranium-235
Chapter Q1 Aseptic techniques involves taking
5. (a) (i) Generate electrical energy as 1 Microorganisms actions and following procedures
an alternative to fossil fuel designed to create a condition
Produce radioactive isotopes free from contamination by
which are useful in various Checkpoint 1.1 microorganisms.
fields such as medicine, Q1 Algae, bacteria, fungi, protozoa and Q2 • Sterilisation using heat, such as
agriculture and industry virus boiling or heating a material or an
(ii) • The nuclear fission reaction Q2 (a) • Consist of genetic material object
produces two or three new and protein coat only • Sterilisation using chemicals, such
neutrons. • Reproduce using the as using antiseptics or disinfectants Form
• These neutrons bombard materials of the living host on a material or an object
other uranium nuclei and cell. • Sterilisation using radiation, such
cause the nucleus to split (b) • Have chloroplasts as shining gamma rays onto 5
to produce more neutrons. • Have cell walls made of material or an object
• Continuous fission will cellulose
occur if at least one Q3 Antibiotics are used to kill or inhibit
neutron splits another Q3 According to their shapes such as the growth of bacteria.
uranium nucleus. coccus for spherical bacteria, vibrio
(b) The process of nuclear fission for comma-shaped bacteria, bacillus
triggers a chain reaction. A for rod-shaped bacteria and spirillum SPM Practice 1
well-controlled chain reaction is for spiral bacteria
used to generate nuclear energy. Q4 pH, temperature, nutrients, light, Objective Questions
If a chain reaction occurs humidity 1. A 2. D 3. D 4. A 5. B
uncontrollably, an explosion can Q5 (a) The rate of growth of 6. C 7. A 8. B 9. B 10. D
occur. microorganisms except viruses 11. A
(c) I support increases when the amount of
• Fossil fuels in Malaysia are nutrients increases provided all Subjective Questions
declining, nuclear power other factors remain constant. 1. (a) Microorganisms are active when
stations are suitable to be used (b) All microorganisms except nutrients are present.
to solve this issue photosynthetic microorganisms


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Science SPM Answers
(b) (i) Presence of nutrient 6. Petri dishes A, B and C Q2 (a) To change nitrogen gas in the
(ii) Number of Bacillus sp. are covered and sealed atmosphere into nitrates
colonies with cellophane tape. (b) To change ammonium
(c) If there is a presence of 7. Petri dish A is kept compounds produced from
nutrients, then the rate of growth inverted in a dark decomposition of dead remains
of bacteria increases. cupboard at room into nitrates
(d) Iodine solution containing weak temperature. Petri dish (c) To change nitrates to nitrogen
acid is used as an antiseptic to B is kept inverted in the gas
prevent bacterial growth on the refrigerator at 5°C. Petri Q3 (a) Through nitrogen-fixing process
surface of injured skin. dish C is kept inverted in or nitrification process
2. (a) (i) The clear zone around an incubator at 70°C for (b) Through denitrification process
the filter paper soaked three days. Q4 When plants and animals die, the
in penicillin of high 8. After three days, the proteins in their bodies will be
concentration is the biggest. number of bacterial decomposed to produce ammonium
(ii) A more concentrated colonies on the surface compounds.
penicillin affects the growth of the agar in each Petri Q5 Decomposition of dead plants
of bacteria more dish is counted and and animals produce ammonium
(b) (i) pH, temperature recorded on a table. compounds. Nitrifying bacteria
(ii) Concentration of antibiotic (iv) changes these ammonium
(c) No clear zone Number of compounds to nitrates.
3. (a) To kill or inhibit the growth Petri Temperature bacterial
of microorganisms especially dish (°C) colonies Checkpoint 2.4
bacteria and fungi Q1 • Use of quality breeds
(b) Vaccine A Room • Use of modern technology
(c) • Processing food such as temperature • Optimum use of land and irrigated
vinegar in the food industry areas
• Curing of hide to produce B 5 • Research and development
leather in the leather industry • Education and guidance for farmers
(d) • Cause diseases C 70 • Efficient land management
• Spoil food
4. (a) What is the effect of temperature Checkpoint 2.5
on the growth of Bacillus sp.? Chapter Nutrition and Food Q1 • Pasteurisation is a process where
2
(b) The growth of Bacillus sp. is the Technology milk is heated up to 72°C for 15
highest at room temperature. seconds or 63°C for 30 minutes
(c) (i) To study the effect of Checkpoint 2.1 and quickly cooled and packed.
temperature on the growth of Q1 (a) The energy content of a food • This process does not kill all the
microorganisms. (b) Bomb calorimeter bacteria but it preserves the flavour
(ii) Manipulated variable: Q2 Protein, carbohydrate, fats, vitamins of the milk. As a result, pasteurised
Temperature and minerals milk can only be kept for a few
Responding variable: Number days.
of Bacillus sp. colonies Q3 (a) Males are generally more active Q2
Constant variable: Types of than females, further more;
males have larger body size than
bacteria females Additive Purpose Example
(iii) 1. Three Petri dishes, each Preservative To kill Sodium
containing 10 cm of (b) Teenagers are still growing, and microorganisms nitrite
3
they are generally more active.
sterile nutrient agar, are so that food can
prepared and labelled as Checkpoint 2.2 last longer
A, B and C.
2. One end of the wire loop Q1 (a) Nutrients needed by plants in Colouring To make the Antocyanin
Form
is sterilised by heating it fairly large quantities. Examples food more
in a Bunsen flame. Then are potassium and nitrogen. attractive
5
it is removed from the (b) Nutrients needed by plants in Bleach To make the Benzoyl
flame and left to cool to very small quantities. Examples food appear peroxide
room temperature. are boron and zinc. white and clean
3. The end of the wire Q2 (a) Yellowing of leaves
loop is dipped into the (b) Stunted growth Flavouring To imitate MSG
Bacillus sp. culture (c) Dead tissues at tip and edges of natural flavours
solution. leaves Stabiliser To give food a Gelatine
4. The end of the wire loop Q3 (a) To block the sunlight so that the firmer texture
is then used to smear growth of algae in culture solution
the bacterial culture in can be prevented Antioxidant To stop fats in Vitamin C
a zig-zag pattern on the (b) To supply oxygen to the root food from going
sterile nutrient agar in bad
petri dish A. Checkpoint 2.3
5. Steps 2 to 4 are Q1 Nitrogen is the important element for Emulsifier To prevent fats Lecithin
repeated for Petri dishes the formation of proteins and nucleic from separating
B and C. acids in living organisms. from mixture

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Science SPM Answers
Checkpoint 2.6 (c) (i) To determine the calorific cylinder and put it into the
value of different food boiling tube.
Q1 By enacting the Food Act 1983 and classes. 3. Clamp the boiling tube to
the Food Regulation 1985 to ensure (ii) Manipulated variable: Type the retort stand and put the
the foods that are processed are of food samples thermometer.
safe, wholesome and fit for human Responding variable: 4. Fix the position of the
consumption Calorific value of food thermometer using the cotton
Q2 Information on the labels of samples wool.
processed food should include: Constant variable: Mass of 5. Record the initial temperature
• The name of the food water of the distilled water.
• The ingredients and chemicals (iii)
used in processing the food Shield 6. Pin the cashew nut to the
• The quantity of each ingredient needle and fix its position
• Expiry date using the plasticine.
• The name and address of the 90 100 Thermometer 7. Burn the cashew nut using
manufacturer 80 a Bunsen burner and record
Cotton wool the highest temperature of
Q3 Has the halal logo as certified by 70 60 50
JAKIM 40 Boiling tube the distilled water after the
cashew nut has finished
30
SPM Practice 2 20 10 burning.
Distilled water 8. Replace the water in the
Objective Questions Retort boiling tube.
1. B 2. A 3. C 4. D 5. A stand Food sample 9. Repeat steps 1 to 8 using
6. D 7. C 8. A 9. B 10. B Needle bread and anchovies placed
11. C 12. C 13. D 14. A 15. C inside the crucible.
16. A 17. A 18. C 19. B 20. D Plasticine 10. Calculate the calorific value
of each food sample using
21. A 22. A 23. B 24. C 25. B the following equation:
26. D 1. Weigh the cashew nut using Calorific value of food
Subjective Questions a digital scale and record its 4.2 J g ° C × Mass of water (g)
–1
–1
1. (a) To study the effect of deficiency mass. × Temperature change (°C)

in nitrogen on the growth of 2. Measure 20 ml of distilled = Mass of food (g) × 1000
plants water using a measuring
(b) (i) Presence of nitrogen in the
culture solution 11. Record your results in a table.
(ii) Growth condition of the plant
(iii) Original size of corn seedling Mass Initial Final Rise in Calorific
/ Volume of culture solution Food of food temperature temperature temperature value of –1
(c) Yellowing of leaves sample sample of water (°C) of water (°C) food (kJ g )
(g)
(°C)
2. (a) (i) Fat: Q
Reason: Margarine has the Cashew nut
highest fat content Bread
(ii) Protein: P
Reason: Milk has the highest Anchovies
protein content
(iii) Carbohydrate: R 5. (a) (i) Food processing involves as the growth of bacteria and
Reason: Rice has the highest making change to a food to prevent bananas from spoiling.
carbohydrate content make it last longer, make it • By processing bananas into Form
(b) (i) Carrots more appealing or tastier to banana chips and using
(ii) Margarine consume. vacuum packaging to delay
(c) High blood pressure (ii) • To make food last longer spoilage in the chips and to 5
3. (a) P : Nitrogen-fixing bacteria • To kill microorganisms maintain the colour, flavour
and texture of the bananas.
Q : Nitrifying bacteria (b) Chemicals are added into • Dehydration or removal of
R : Denitrifying bacteria food to improve the taste water and moisture by smoking
and appearance of food. All
(b) Nitrogen is absorbed in the form chemicals added to food are
of ions, for example nitrate ions in the right quantity for human
(c) The decomposition of the consumption. Sweeteners are Chapter Sustainability of the
3
proteins in the body tissue of added to make food sweeter. Environment
dead animals and plants into Flavourings are added to imitate
ammonium compounds the natural flavour of food. Food Checkpoint 3.1
(d) Bacteria/fungi colouring is added into food such Q1 (a) Carbon footprint is the total
4. (a) Which classes of food has the as cake and ice cream to make amount of greenhouse gases,
highest calories? them appear more attractive. which is carbon dioxide produced
(b) Cashew nut has a higher (c) • By chilling the banana between from human activities such as
calorific value compared to 10°C to 14°C to slow down vehicle emissions, open burning
albumen powder and cooking oil the enzymatic process as well and burning of fossil fuels.

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06 Ans Focus SC SPM.indd 405 24/02/2023 3:33 PM