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Maggie Spenceley
HEINEMANNQueensland
Science Project
Middle Years ScienceA Contextual Approach
hi.com.au/scicontextual
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Introducing science 2
Thinking about 2 1.1 What scientists do 4 1.2 Observation and inference 8 1.3 Is it fair? 13
Chapter review 18
Staying alive 20
Thinking about 20 2.1 Run away or hide? 22 2.2 Well adapted 25 2.3 Energy moves 31
Chapter review 38
Changing materials 40
Thinking about 41 3.1 The basics 42 3.2 Useful changes 52
Chapter review 56
Big changes 58
Thinking about 58 4.1 Earth—part of a system 60 4.2 Closer to home 62 4.3 Fossils tell tales 68
Chapter review 74
Safety first 76
Thinking about 76 5.1 Forces act on us all the time 78 5.2 Inertia 85
Chapter review 90
Tomorrow,s weather 92
Thinking about 92 6.1 What is weather? 94 6.2 Climate change 108
Chapter review 112
Contents
Middle Years Science: A Contextual Approachiv
Use it again 114
Thinking about 114 7.1 What is waste? 116 7.2 Metal and glass 119 7.3 Plastics 123 7.4 Packaging 127
Chapter review 132
Water 134
Thinking about 134 8.1 Where does it come from? 136 8.2 Drinking water 139 8.3 Used water 144
Chapter review 150
Energy converters 152
Thinking about 152 9.1 Stored and moving energy 154 9.2 Changing energy 158 9.3 Renewable or not? 162
Chapter review 170
Under the skin 172
Thinking about 17210.1 Living or not 17410.2 Cells 17910.3 Grouping 184
Chapter review 190
Glossary 191
Index 194
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Contents continued...
What do you think about when you hear the word ‘science’?Write down some of your ideas and share them with a partner. Working together, write one sentence that explainswhat you think of when you hear the word ‘science’. Compare what you have written with a dictionary definition.
Use Worksheet 1.1 ‘What is science?’ to record your ideas.
What do scientists do and where do they work? Record your ideas in Worksheet 1.1, and share your ideas with a friendand then with the rest of the class.
In Worksheet 1.1, you have been provided withthe names of a number of different types of scientists. Find out what each of them studies.
Introducing
science
Look around your class. Not everyone is the same. Peoplecan be different heights and have straight or curly hair. Some differences we cannot see, such as personalities and different interests.
Have you ever been talking about what you want to do when you grow up and people say, ‘You would be good at that—you have the personality for it.’? What characteristics do youthink scientists need? An important characteristic is curiosity.Scientists want to know how things work and why things happen. It is curiosity, and determination to have it satisfied, that keeps scientists going until they have some answers.
Scientists enjoy learning and applying their knowledge infamiliar and unfamiliar situations. They are observant. Theygather their knowledge from many sources and recognise that different people can view the same information in different ways. They work well on their own, but can also work as partof a group. They gather information, analyse it and reach a conclusion based on information not on emotion.
FigureFigure 1 .1Which of these photographs represents a scientist atwork? If you said the one inthe bottom photo, you wouldbe correct. However, the person in the top photo isalso a scientist hard at work.
1.1
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Your mission is to ask a question about something in the naturalworld and carry out a fair test tofind the answer. Keep a journal that records:• any research you did and the
resources you used• the method for your fair test• any modifications you made to
the method• the results and your explanation
of the results.
Present your question and theanswer to the class.
cataractdependent variablefair testgeologistindependent variableinferenceintraocular lenslensobservationophthalmologistpharmacistqualitativequantitativetrachomavalid inference
Introducing
science
Figure 1.2We can see that people are verydifferent. However, some differences wecannot see.
Middle Years Science: A Contextual Approach4
Scientists are involved in a wide variety of professions. Let’slook at two.
Figure 1.3Geologists work in the field as well as in an office.
olved in a wide var
1.1
geologists
Geologist
Middle Years Science: A Contextual Approach8
Observation is the gathering of information about the world, using our senses. We use our observations as the starting point for thinking, reflecting and making judgements. We gathermost of this information through our sense of sight. However,the other four senses are also powerful observational tools. As we think about observations and try to interpret them, we aremaking inferences.
When you visit a doctor, the doctor observes your symptomsand makes a diagnosis. He or she then prescribes a treatment for your illness. Doctors make observations and then linkthem to their knowledge, to come up with an inference or aneducated guess of what is wrong with you. Because doctorshave good knowledge and a lot of experience, the inference isusually correct. If they do not have enough information, they may send you for tests so that they can make more observations and gather more information on which to base an inference.
ObservationThe observations we make are influenced by:
• our experience and knowledge• how much attention we are paying• the amount of training in observation we have had.
Look at Figure 1.7. It is unlikely that you will have seen thisobject before but you probably recognise it as a postagestamp. Why? Because you know what stamps in Australia look like and this object has many of the same characteristics. You observed the type of edge and the information that waswritten on it, value and country name. You then made aneducated guess, an inference, that it is a postage stamp.
th i
1.2
Figure 1.7What is this?What
questions 1 .1
1. What does a geologist study?2. What is pharmacology?3. What is an important characteristic of What is
scientists?scient
4. List three other characteristics of scientists.
5. What skill is listed as necessary for both geologists and pharmacists?
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I can tastethe water.It’s awful.
II can seethat the dog isbrown and white
and wet.a
I can feel thatthe fur is soft
and wet..I can smell
his wet fur.
I can hear hiswet ears flappingand his barking.
Figure 1.8We use our five senses toobserve the world around us.
Try this exercise to find out.
Aim: To test your observation skills.
Materials:
pencil10-cent coin (for later)Worksheet 1.3 ‘How observant are you?’
What to do:
Draw two circles that you think are the same size as a 10-cent coin. Don’t look at the coin while you are doing this. In one of the circles, draw the face of the coin (heads). In theother, circle draw the obverse side (tails). Put in as much detail as you can remember.
Use Worksheet 1.3 for your drawings and to test your observation skills in other ways.
S C I E N C E work 1.1
1.3
It is likely that you passed an unknown person on the way to school today. Do you remember what they were wearing? Itis unlikely because there was no need for you to rememberthem and you would not have been paying attention. People who have to be observant as part of their job are trained tobecome more efficient observers. Police, forensic scientistsand other scientists learn how to see details that othersmight miss. You can learn to be more observant by becoming more systematic in the way that you look at things and by paying attention to your environment at all times.paying a
Chapter review
Middle Years Science: A Contextual Approach18
Check1. Use Worksheet 1.8 ‘Key terms’ to check your
knowledge of the key terms.
2. For each of the following, state whether it is a qualitative orquantitative observation.a. The rock is hard.b. It took me 10 minutes to get to school.c. The reading on the scale was 2.5 kg.d. The first pillow I tried was softer than the second one.e. We had 14 mm of rain last week.
3. Make a list of the characteristics of a scientist.4. Explain the difference between a dependent variable and
an independent variable.
Apply5. Are communication skills important for scientists? Use
information from the story about the geologist and the pharmacist to support your answer.
1.8
Figure 1.17
reflectionDo you think you would make a good scientist? Explain why or why not.
Present your mission to the class.
• What comments did members of the class make about your presentation?
• What would you change about the way you undertook or presented themission?
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6. How is an inference different from a guess?7. Do you think that police and forensic scientists would use
qualitative or quantitative evidence when presenting a case in court? Explain.
8. In an experiment, why is it important to control the factors that are not being investigated?
9. a. Imagine you have been asked to design an experiment to find out whether salt or sugar dissolves more easily. What would be the:i. independent variable?ii. dependent variable?
b. Suggest two other variables you would have to control.
Challenge10. Why is it important that pharmacists study pharmacy law?11. Suggest ways that you could improve your observation
skills.12. Use the Internet to find the name of a famous scientist.
State when he or she lived and describe in your own words what they are famous for. (The Eureka People’s Choice website could be a good place to start.)
13. Think about ways you are working as a scientist in your everyday life. Select one of the ways and draw a picture orwrite a few sentences to show others your idea.
