ii © 2010 Marshall Cavendish International (Singapore) Private Limited

Writing TeamNoraini Binte AbbasTeo-Gwan Wai LanWinnie PehAkshita NandaJacqueline WooManisha Nayak

Based onthe latest Primary Science syllabus

Science PSLEPSLERevision Guide

2nd Edition2nd Edition

From the creators of

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This section analyses challenging examination questions and provides strategies that you can use to answer them correctly.

This section comprises fi ve full-colour detachable thematic maps that link the concepts across the chapters in each theme. Use these maps as a guide to help you recall all the concepts you need to master for the PSLE. This section also contains thematic glossaries to help you identify key concepts and serve as a spelling list.

This section explains the process skills listed in the latest Primary Science syllabus that you are required to know and helps you to sharpen your application of these process skills.

This section contains a Practice Examination Paper to prepare you for the PSLE. Assess yourself by comparing your answers with those provided.

Dear pupil,

The PSLE is a challenge, and to conquer it, you need to be equipped with the right tools. The Science PSLE Revision Guide (2nd Edition) is a unique tool that will guide you through your PSLE revision in a thorough and organised manner.

This book has been specially designed to help you understand and tackle the various challenges posed by the PSLE.

Let us take a look at the fi ve sections of this book and what they have in store for you!

To get the most out of this book, follow our highly recommended 5-step plan to conquer the PSLE!

Step 1Use Section A to revise all the concepts covered from Lower Block to Upper Block.

Step 5Finally, use Section D to assess yourself. Compare your answers with those provided.

Step 3Use Section B to learn and sharpen your application of process skills.

Step 2Use Section E to understand the big picture and concepts that you have studied.

Step 4Use Section C to train your analysis of examination questions and how to answer them correctly.

How To Use This Book

Section

Revision NotesASectio

n

Process SkillsB

Section

Case StudiesCSectio

n

Practice Examination

Paper

DSectio

n

Thematic MapsE

This section contains revision notes on the fi ve themes that are covered from Lower Block to Upper Block. The notes are presented in an easy-to-read format, with charts, tables and diagrams.

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iv © 2010 Marshall Cavendish International (Singapore) Private Limited

PrefaceSection A

IntroductionProvides an introduction to the theme and shows you the connection to other themes

Read more in Links the topic you are learning to related concepts that you will learn at higher levels

Remember? Provides links to concepts you learnt in earlier levels or chapters

My Revision Checklist Helps you chart the course of your revision through an acknowledgement of your understanding of each learning point and the date you carried out this exercise. The date will serve as a reference and reminder if you need to revisit the chapter

OverviewProvides a summary of all the Life Science and Physical Science chapters that you need to learn in Lower Block and Upper Block

4 Diversity

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5Diversity

Case StudiesIntroduction To Diversity

Diversity Theme — Content

Good to KnowProvides additional but relevant information that gives you an edge to score well

Good KnowtoUnwanted plants are known as weeds. Weeds compete with useful plants for

sunlight, water and nutrients. Hence, they are harmful and are removed by farmers and gardeners. Some common weeds are the lalang and the mimosa.

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Wrong concept : Plants are non-living things because they do not move from place to place. Right concept : Although plants do not move from place to place, they can move certain parts by themselves to respond to changes around them. Wrong concept : Things that can move are living things. Right concept : Not everything that can move is a living thing. For example, a car can move, but

it is not a living thing.

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Get it Right! Points out and corrects common misconceptions that you may have

Read more in UB – Chapter 10

t Right!

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• Plants reproduce to ensure the survival and continuity of their own kind.

• In sexual reproduction, a male reproductive cell fuses with a female reproductive cell.

• In asexual reproduction, only one parent is involved.

?Remember

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Re

1

2

3

I can state that classifi cation is the process of putting

things into groups.

I can explain why we need to classify things.

I can classify things according to their common

characteristics.

I can use classifi cation tables or diagrams to show

similarities and differences.

My Revision Checklist

Section

Points

Not sureI know

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19© 2010 Marshall Cavendish International (Singapore) Private Limited

Diversity 19Di it

Application To Daily Life

A unique characteristic of living things is

their ability to respond to changes in their

surroundings. Winter is one example of an

extreme environment that many organisms

need to respond to, in order to survive.

Some animals respond to the extreme cold by

falling into a deep sleep or hibernating. This

allows them to escape the cold environment.

Since it is very diffi cult to fi nd food during

winter, animals that hibernate rely on their

body fat to survive. This is why they begin to

store food in the form of body fat, as early

as the end of summer and continue all the

way through autumn.

In order to survive through winter, the bodies

of hibernating animals have some interesting

features. Firstly, the body temperature drops,

such that it almost matches the surrounding

temperature. Secondly, the heart rate and

breathing also slow down. These features

help to reduce the amount of energy

required, allowing the hibernating animal

to survive through winter with the limited

amount of body fat. If the animal stayed

awake and moved around a lot, the body fat

would be used up before winter was over.

Thus, it is important for animals that hibernate,

to store suffi cient body fat before winter. If

there is a shortage of food during autumn,

the animal might not have suffi cient body fat

to survive until spring, when it can begin to

fi nd food again.

Food For Hibernation

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Application To Daily Life Helps you understand how Science is infused in your life

Lower BlockDiversity

1

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Diversity

Theme Life SciencePhysical Science

Lower BlockUpper Block

Lower Block Upper Block

Diversity • Things around us – Chapter 1 Classifying things – Chapter 2 Living and

non-living things• Life around us – Chapter 3 Plants – Chapter 4 Animals – Chapter 5 Fungi and bacteria

—

• Things around us – Chapter 1 Classifying

things – Chapter 2 Living and

non-living things – Chapter 6 Exploring materials

—

Cycles • Life cycles – Chapter 7 Life cycles

• Reproduction – Chapter 9 From parents to young – Chapter 10 Reproduction in plants – Chapter 11 Reproduction in humans

• Matter – Chapter 8 Matter and its three states

• Water – Chapter 12 Water and changes of state

Systems • Living systems – Chapter 13 What is a system? – Chapter 14 Your amazing body

– Chapter 15 The digestive system – Chapter 16 Plants and their parts

• Living systems – Chapter 17 The plant transport system – Chapter 18 Air and the respiratory system – Chapter 19 The human circulatory system – Chapter 20 The unit of life

• Non-living systems – Chapter 13 What is a

system?

• Non-living systems – Chapter 21 Electricity

Interactions

—

• Interactions in ecosystems – Chapter 24 Living together – Chapter 25 Characteristics of the environment – Chapter 26 Food chains and food webs – Chapter 27 Adaptations for survival – Chapter 28 Man’s impact on the environment

• Interactions of forces – Chapter 22 Magnets• Interactions of forces – Chapter 23 Forces

Energy

— • Energy from food and transfer of energy – Chapter 31 Energy in food

• Energy around us – Chapter 29 Light – Chapter 30 Heat and temperature

• Energy around us – Chapter 32 Forms, uses and sources of energy

Case StudiesCase StudiesOverview Of Primary Science Chapters

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396

© 2010 Marshall Cavendish International (Singapore) Private Limited

If ball A rolls off the wall, it will bounce up to point P as shown in the diagram below.

(b) Compared with point P, how high will Ball B bounce up to if it rolls off the wall? [1] (c) When will the kinetic energy possessed by both balls be converted to sound

energy?

[1] 42. The shadow of a block is formed on the fl oor as shown below.

(a) Why is it possible to see a shadow?

[1] (b) If the block remains at the same position on the ground, explain how its shadow

can change in position as shown below.

[2]

ball B

ball A

ball A at point P

ground

block

block

fl oor

fl oor

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Reas o ns

Kno led e

C ncept

Worked Example 3

Process skill

Let’s work it uto

Answer

Reas o n

What Do These Observations Mean?Smart!Study

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© 2010 Marshall Cavendish International (Singapore) Private Limited

• Step 5: If ythe microscope.

When you are asked to observe something, ask yourself:

• What information about the object or event is relevant

to my investigation?

• Which senses shall I use to gather this information?

• What instrument can I use to help me gather the

information more accurately?

• What characteristics, details or changes should

I look out for?

My Skill Checklist Observing

Information Sense Instrument

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h ll di h i l ( i ) i i i d

Skill 5: Communicating

What This Process Skill Is• Communicating is the skill of:

− transmitting (sending or sharing of) information;

− receiving information.

• When you communicate scientifi c information, the information can be presented in various forms, such as:

− by talking (verbal);

− by using pictures, drawings or diagrams (pictorial);

− by using tables (tabular);

– by using graphs (graphical).

How This Process Skill Is Used• You communicate when you want to share your ideas or the fi ndings of your experiment

with others.

• You communicate when you need to understand the information you received.

Process Skill Tips (Diagrams)

A. Drawing Diagrams

• Diagrams help us to understand ideas that are diffi cult to explain in words.

• In Science, you can draw diagrams like scientifi c drawings to describe something you observed, explain an idea or present the results of an experiment.

• In order to help other people understand your drawings, especially in your examination answers, do be careful and draw clearly.

Guidelines On Drawing Scientifi c Drawings As Clearly As Possible:• Ensure your drawing is clean, neat, simple and clear.

• Use a sharp pencil and ensure you have an eraser ready in case you make mistakes.

• Draw clean and clear lines. Do not draw fuzzy or broken lines.

• Do not shade your drawing, unless you are instructed to do so.

• Give your drawing a clear and concise title that explains completely what is illustrated.

• All labels should be on one side of your drawing (left or right) as much as possible.

• Labels should be written horizontally. Do not write in cursive handwriting.

• Use a ruler to draw straight label lines. Do not use arrows for label lines.

• Label lines should point to the centre of the structure being labelled. Do not cross label lines.

• If you are drawing what you see using a microscope, include the magnifi cation used.

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Section B

Section D

Section EPractice Examination PaperProvides you an avenue to put all your knowledge and skills into practice before the PSLE

Thematic MapGives an overview of all the concepts learnt in each theme in Lower Block and Upper Block

GlossaryGlossary can be used as a summary of the key concepts and as a spelling list

IndexProvides easy reference to an extension of key terms and concepts in the book

Study Smart Provides tips on verifying various hypotheses and guidelines on studying for the PSLE

My Skill ChecklistEnsures that you are well-equipped to tackle PSLE process skills questions

What This Process Skill IsProvides an explanation of process skills

How This Process Skill Is UsedExplains how and in what context the various process skills can be used

Process Skill Tips Provides an example of how the process skill is applied

Section C

Answer Provides you with answers to the questions

Reason Provides explanations for the answers

Process SkillHighlights the process skills required to answer the questions

Let’s Work It Out Shows you how to answer the questions one step at a time

KnowledgeExplains the questions by drawing on what you have learnt

ConceptHighlights the concepts required to answer the questions

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Contents

ThemeDiversity

Cycles

Systems

Interactions

Energy

LevelLower Block

Lower Block

Upper Block

Lower Block

Upper Block

Lower BlockUpper Block

Lower Block

Upper Block

Chapter1. Classifying Things2. Living And Non-Living Things3. Plants4. Animals5. Fungi And Bacteria6. Exploring Materials

7. Life Cycles8. Matter And Its Three States9. From Parents To Young10. Reproduction In Plants11. Reproduction In Humans12. Water And Changes Of State

13. What Is A System?14. Your Amazing Body15. The Digestive System16. Plants And Their Parts17. The Plant Transport System18. Air And The Respiratory System19. The Human Circulatory System20. The Unit Of Life21. Electricity

22. Magnets23. Forces24. Living Together25. Characteristics Of The Environment26. Food Chains And Food Webs27. Adaptations For Survival28. Man’s Impact On The Environment

29. Light 30. Heat And Temperature31. Energy In Food32. Forms, Uses And Sources Of Energy

Page69

20273943

546371758690

104105108111119122133141147

166175187200214222238

256264272279

Section A — Revision Notes

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Sharpen Your Skills!Skill 1: ObservingSkill 2: ComparingSkill 3: ClassifyingSkill 4: Using Apparatus And EquipmentSkill 5: CommunicatingSkill 6: InferringSkill 7: PredictingSkill 8: AnalysingSkill 9: Generating PossibilitiesSkill 10: EvaluatingSkill 11: Formulating HypothesisSkill 12: Creative Problem SolvingSkill 13: Decision-makingSkill 14: Investigating

What Do These Observations Mean?

Examination Tips

Page297300303306307310323325326327328329330331333

338

340

Section B — Process Skills

Worked Example 1Worked Example 2Worked Example 3Worked Example 4Worked Example 5Worked Example 6Worked Example 7Worked Example 8Worked Example 9Worked Example 10

Page347349350353356358361363365367

Section C — Case Studies

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Using Thematic MapsMap 1: Diversity GlossaryMap 2: Cycles GlossaryMap 3: Systems GlossaryMap 4: Interactions GlossaryMap 5: Energy Glossary

Index

Index

Page396397398399400401402403404405406

Page407

Part 1 (Multiple Choice Questions)Part II (Open-ended Questions)Answers

Page370385393

Section D — Practice Examination Paper

Section E — Thematic Concept Maps / Glossaries

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4 Diversity © 2010 Marshall Cavendish International (Singapore) Private Limited

Case StudiesCase StudiesIntroduction To DiversityThere is a great diversity of living and non-living things in the world we live in. Living things, such as plants, animals, fungi and bacteria, come in a variety of shapes and sizes. Some living things are very small such that we need to use a microscope to see them, while other living things can reach heights of more than 100 metres. Living things also vary in many other ways, such as how they obtain energy, how they move and where they live.

Diversity can be seen in non-living things as well. Non-living things can be made of different materials, such as wood, rubber, metals, fabric, ceramics, glass and plastics. Different materials also have different characteristics or properties, such as hardness, strength, fl exibility, ability to fl oat or sink in water, transparency and electrical conductivity.

Due to this diversity of living and non-living things, we need to classify and organise them into groups, in order to learn more about them. There are many ways to group things. In fact, scientists have created some groups based on the major features or characteristics that things share.

Diversity Theme — Content

Diversity Chapter 1 Classifying things

Chapter 2 Living and non-living things

Chapter 3 Plants

Chapter 4 Animals

Chapter 5 Fungi and bacteria

Chapter 6 Exploring materials

—

Theme Lower Block Upper Block

• Chapter 2 Living and non-living things

• Chapter 3 Plants

• Chapter 4 Animals

• Chapter 5 Fungi and bacteria

• Chapter 6 Exploring materials

• Chapter 1 Classifying things

• Chapter 3 Plants

• Chapter 4 Animals

• Chapter 5 Fungi and bacteria

• Chapter 6 Exploring materials

• Chapter 13 What is a system?

Connection to other topics:

Chapter 1 Classifying things

Chapter 2 Living and non-living things

Chapter 3 Plants

Chapter 4 Animals

Chapter 5 Fungi and bacteria

Chapter 6 Exploring materials

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Case Studies• Chapter 2 Living and non-living things

• Chapter 7 Life cycles

• Chapter 9 From parents to young

• Chapter 10 Reproduction in plants

• Chapter 16 Plants and their parts

• Chapter 17 The plant transport system

• Chapter 20 The unit of life

• Chapter 27 Adaptations for survival

• Chapter 31 Energy in food

• Chapter 2 Living and non-living things

• Chapter 7 Life cycles

• Chapter 9 From parents to young

• Chapter 11 Reproduction in humans

• Chapter 20 The unit of life

• Chapter 26 Food chains and food webs

• Chapter 27 Adaptations for survival

• Chapter 28 Man’s impact on the environment

• Chapter 31 Energy in food

• Chapter 2 Living and non-living things

• Chapter 8 Matter and its three states

• Chapter 12 Water and changes of state

• Chapter 21 Electricity

• Chapter 29 Light

• Chapter 30 Heat and temperature

• Chapter 2 Living and non-living things

• Chapter 24 Living together

• Chapter 26 Food chains and food webs

• Chapter 28 Man’s impact on the environment

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Big Questions• What is classifi cation?

• Why do we classify things?

• How can we classify things?

1. What Is Classifi cation? • We usually put things into groups. The process of putting things into groups is

called classifi cation.

• When we classify things, we sort them into groups based on their characteristics.

2. Why Do We Classify Things? • Classifying things makes it easy for us to show similarities and differences.

– Things with similar characteristics are classifi ed into the same group. These things are usually similar in at least one way.

– Things with differing characteristics are classifi ed into different groups. These things are usually different in at least one way.

• Classifying things also helps us to gain a better understanding of the things we are studying. For example, classifi cation helps us to identify newly discovered living things and to determine whether there is any relationship between them and a previously identifi ed living thing.

• Classifying things helps us to organise them in an orderly and systematic manner. This in turn allows us to fi nd or locate them easily.

Before classifi cation

Classifying Things1Chapter

Chair Cup Dog Giraffe Goldfi shLamp Parrot Radio Snake Table

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3. How Can We Classify Things? • Classifi cation can be shown using classifi cation tables or diagrams.

• We classify things according to their similarities. For example, we can classify things according to their shapes, sizes, colours and patterns.

• The things in the box below may be grouped according to shape, colour or size.

After classifi cation

Dog

Giraffe

Goldfi sh

Parrot

Snake

Chair

Cup

Lamp

Radio

Table

Living Things Non-living Things

Read more in LB – Chapter 2

According to Shape

Triangle Circle

According to Size

Small Big

According to Colour

White Grey

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• There is usually more than one way to classify a collection of things. The following diagram shows some common ways of classifying things.

can be classifi ed as

can be classifi ed according to

can be classifi ed according to

Things

Living things Non-Living things

Form Nutrition Electrical property

Magnetic property

Thermal property

Degree of transparency

to light

Movement Flexibility Hardness

Read more in LB – Chapters 2, 3, 4, 5 & 6

1

2

3

I can state that classifi cation is the process of putting things into groups.

I can explain why we need to classify things.

I can classify things according to their common characteristics.

I can use classifi cation tables or diagrams to show similarities and differences.

My Revision ChecklistSection Points Not sureI know

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