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Transcript of HSW – Answering AS questions How Science Works Answering AS questions Version 1.01 Copyright ©...
HSW – Answering AS questions
How Science Works
Answering AS questions
Version 1.0 1 Copyright © 2008 AQA and its licensors. All rights reserved.
HSW – Answering AS questions
Version 1.0 2 Copyright © 2008 AQA and its licensors. All rights reserved.
What have mosquitoes to do with your specification?
Look at the Assessment Objectives
AO2 Application of knowledge and understanding of science and of How Science Works
Candidates should be able to: • apply scientific knowledge …to unfamiliar situations
HSW – Answering AS questions
Version 1.0 3 Copyright © 2008 AQA and its licensors. All rights reserved.
What have mosquitoes to do with your specification?
Look at the Assessment Objectives (p46)
AO3 How Science Works
Candidates should be able to • analyse, interpret, explain and evaluate the methodology, results and impact of … others’ experimental and investigative activities.
HSW – Answering AS questions
What this means to you
Your examiners must test these assessment objectives.
Therefore your Unit tests must include
•Opportunities for you to apply your knowledge to unfamiliar situations
•Examples of others’ experimental and investigative activities for you to analyse, interpret, explain and evaluate
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HSW – Answering AS questions
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Read the introduction to the question
• Mosquitoes are insects
• Some female mosquitoes feed on human blood.
• They are attracted to humans and land on exposed skin.
• They then pierce the host’s skin and suck blood.
The introduction may provide you with information that you will need later.
Title of presentation
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A simple start
The first parts of most longer questions are often quite simple. Examiners appreciate that giving you something that is easy at the start gives you confidence.
1Both of these traps used heat and carbon dioxide to attract mosquitoes. Explain how each of these might attract a mosquito to a human. (a) Heat (b) carbon dioxide
Remember, the only reason that a question looks simple is because it is simple. No one is trying to trick you.
HSW – Answering AS questions
Version 1.0 7 Copyright © 2008 AQA and its licensors. All rights reserved.
Looking at other people’s investigationsWhat were the scientists investigating?• Start by identifying the dependent and independent
variables • Put them in this simple template.
The effect of [the independent variablethe independent variable] on the [dependent variabledependent variable]
• In this case . . . The effect of [the type of trapthe type of trap] on the [number of number of mosquitoes caughtmosquitoes caught]
Having a clear idea what the investigation is about is an essential first step towards understanding any investigation.
HSW – Answering AS questions
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Looking at other people’s investigations
• Take time to make sure that you understand exactly what they did.
The scientists moved the traps randomly between 12 different sites over 12 nights. Each night the traps were at a different site.
Sometimes a simple drawinghelps
12 different sites
HSW – Answering AS questions
Version 1.0 9 Copyright © 2008 AQA and its licensors. All rights reserved.
Looking at other people’s investigations
• Take time to make sure that you understand exactly what they did.
The scientists moved the traps randomly between 12 different sites over 12 nights. Each night the traps were at a different site.
Sometimes a simple drawinghelps
Night 1Trap A
Trap B
HSW – Answering AS questions
Version 1.0 10 Copyright © 2008 AQA and its licensors. All rights reserved.
Looking at other people’s investigations
• Take time to make sure that you understand exactly what they did.
The scientists moved the traps randomly between 12 different sites over 12 nights. Each night the traps were at a different site.
Sometimes a simple drawinghelps
Night 2
Trap A
Trap B
HSW – Answering AS questions
Version 1.0 11 Copyright © 2008 AQA and its licensors. All rights reserved.
Looking at other tables• Read the stem of the question.• Make sure that you know what the table headings mean.• Check that you understand what the table as a whole is
telling you.
Here you only need to make sure that you know what the table headings mean
HSW – Answering AS questions
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Check the headings
• Mean tells us the average – the total number of mosquitoes caught divided by the number of nights.
• Standard deviation is a measure of how spread out the results were.
HSW – Answering AS questions
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Looking at tables
Total number of species of mosquito trapped is quite straightforward
HSW – Answering AS questions
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Looking at tables
There are two things to note here. •The data refer to the percentage of mosquitoes.
•These are mosquitoes that are potentially able to transmit Ross River fever. It does not mean that they do.
HSW – Answering AS questions
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Calculations
3 The total number of mosquitoes caught in trap A was 444 90. Calculate the total number of mosquitoes caught in trap A that were able
to transmit Ross River fever. Show your working.
Look at the section on Mathematical Requirements on page 45 of your specification. Your examiners may ask you to use any of the areas of mathematics listed here - not the ones in bold
HSW – Answering AS questions
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Calculations – some hints• Even if you are not very good at mathematics, you should
be able toCalculate a rateCalculate a percentageCalculate magnification and size
Most questions involve one of these
• Always have a go. Don’t leave out any question that involves a calculation.
• Show your working. Even if you get the answer wrong, you could still get a mark for going about the problem in the right way.
HSW – Answering AS questions
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Evaluating data• Evaluation means to judge the worth of something. • Data that you have to evaluate will have some evidence
that will support the idea and some that will not.
4 Evaluate the data in the table and suggest which trap it would be better to use.
HSW – Answering AS questions
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A strategy for evaluating data
Questions requiring evaluation require you to judge the worth of something. Some evidence will support the idea and some will not.
Look for evidence that supports the ideaYou will need to look for the overall trend in the points on a graph or the figures in a table to establish this.
Now look for ways in which the evidence is unconvincing
The key is to get the word “but” into the answer.
HSW – Answering AS questions
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Looking at graphs• Read the stem of the question
• Make sure that you know what the axis labels mean.
• Check that you understand what the graph as a whole is telling you.
HSW – Answering AS questions
Version 1.0 20 Copyright © 2010 AQA and its licensors. All rights reserved.
Looking at graphs• Read the stem of the question
The graph shows the mean number of landings at different distances from the source of the repellent. It also shows the effect of using new repellent and old repellent. The old repellent had been opened 10 weeks earlier.
• The stem provides you with a summary of the information in the graph. It may also give you extra information that you may need when you answer the questions.
HSW – Answering AS questions
• Make sure that you know what the axis labels mean.
Mean numberof mosquitoes landing per minute
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Shouldn’t be a problem here –
the average number landing
on the volunteer’s arm
per minute
HSW – Answering AS questions
• Make sure that you know what the axis labels mean.
Mean numberof mosquitoes landing per minute
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and these are the three treatments
Don’t forget to look at the
key
HSW – Answering AS questions
• Check that you understand what the graph as a whole is telling you
Mean numberof mosquitoes landing per minute
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This bar shows us that when the volunteers were 3.0 metres away from new repellent the mean number of mosquitoes landing per minute was about 1.5
Copyright © 2010 AQA and its licensors. All rights reserved.
The Assessment and Qualifications Alliance (AQA) is a company limited by guarantee registered in England and Wales (company number 3644723)and a registered charity (registered charity number 1073334). Registered address: AQA, Devas Street, Manchester M15 6EX.
Dr Michael Cresswell, Director General.
HSW – Answering AS questions
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