Cambridge IGCSE Twenty-First Century Science 0608 — 2009 May/June Paper 3 · Variant 1

This document consists of 18 printed pages and 2 blank pages. SPA SHW 00387 1/09 V06769/1 © UCLES 2009 [Turn over UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education READ THESE INSTRUCTIONS FIRST Write your Centre number, candidate number and name on all the work you hand in. Write in dark blue or black pen. You may use a pencil for any diagrams or graphs. Do not use staples, paper clips, highlighters, glue or correction fluid. DO NOT WRITE IN ANY BARCODES. Answer all questions. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. * 8 8 3 0 7 1 8 1 0 8 * 21ST CENTURY SCIENCE 0608/03 Paper 3 May/June 2009 1 hour 30 minutes Candidates answer on the Question Paper. No Additional Materials are required. For Examiner’s Use 1 2 3 4 5 6 7 8 9 Total www.XtremePapers.com

2 0608/03/M/J/09 © UCLES 2009 For Examiner’s Use 1 All cells contain genetic information. (a) Where in our cells is this genetic information stored? Put a ring around the correct answer. cell membrane cytoplasm nucleus [1] (b) Complete the following sentences using the correct words from the list below. alleles DNA genes proteins recessive Genes are sections of very long ………………………… molecules. They are instructions that describe how to make ………………………… . Different versions of genes are called ………………………… . These can either be dominant or ………………………… . [3] (c) Joe has cystic fibrosis. This is a genetic condition caused by a recessive allele. Joe’s parents, Henry and Sue, are both carriers of cystic fibrosis. (i) Complete the genetic diagram below to show the different combinations of these two alleles that any children of Joe’s parents could have. Key F = normal allele f = cystic fibrosis allele Sue (mother) F f Henry (father) F ……… ……… ……… ……… ……… [2] (ii) Joe has cystic fibrosis. What combination of alleles does Joe have? … [1]

3 0608/03/M/J/09 © UCLES 2009 [Turn over For Examiner’s Use (d) Sue is pregnant again. Henry and Sue are worried that the new baby may have cystic fibrosis as well. Their doctor says that the embryo can be tested to see if it has the combination of alleles for cystic fibrosis. Their friends give their advice on this. You should have the test. If the embryo has the wrong alleles, the pregnancy can be terminated. There’s no point having the test. It is unnatural to have a pregnancy terminated. You must accept the baby you are given. I’m in favour of the test. If the baby is going to have cystic fibrosis, you can prepare for it beforehand. I’d be worried that the test may damage the baby. I don’t think you should be tested. Adelina Bay Carlos Dacia (i) Who is in favour of Sue having the test? Write down the two correct names. … and … [1] (ii) People often say that certain actions are never justified because they are unnatural or wrong. Who says something which supports this view? Write down the one correct name. … [1] [Total: 9]

4 0608/03/M/J/09 © UCLES 2009 For Examiner’s Use 2 Jose’s father has heart disease. Jose knows that heart disease may be inherited. (a) Which of the following should Jose do to reduce his risk of getting heart disease? Put ticks (✓) in the boxes next to the three correct answers. cycle to work instead of drive eat more fresh fruit and vegetables eat more full fat dairy products increase alcohol intake move away from his family stop smoking cigarettes [2] (b) The graph shows the relationship between the amount of animal fat eaten and the number of deaths from heart disease. Each point on the graph represents a different country. 0 0 animal fat eaten (grams per person per day) deaths from heart disease (per 100 000 per year) 20 40 60 80 100 120 140 50 100 150 200 250 300 350 400 (i) Draw a straight line of best fit on the graph. [1]

5 0608/03/M/J/09 © UCLES 2009 [Turn over For Examiner’s Use (ii) In another country, the amount of animal fat eaten is 60 g per person per day. Use the graph to estimate how many deaths from heart disease occur in this country. … per 100 000 per year [1] (c) Scientists are trying to find a cure for heart disease. A scientist discovers a new treatment and publishes her results in a journal. This work has been checked by other people before it is published. The checking process is called peer review. Which one of the following best describes the other people who check the scientist’s work? Put a tick (✓) in the box next to the correct answer. The work is checked by friends of the scientist members of the public other scientists politicians [1] [Total: 5]

6 0608/03/M/J/09 © UCLES 2009 For Examiner’s Use 3 The Iberian Lynx is a type of wild cat found in Spain. The table shows how the population of the Iberian Lynx has changed. year population of Iberian Lynx 1978 1500 1998 800 2000 600 2002 300 2004 135 2006 120 (a) (i) Describe what happened to the population of Iberian Lynx from 1978 to 2006. … [1] (ii) Calculate the change in the population of Iberian Lynx from 1998 to 2006. … [1] (b) The main prey of the Iberian Lynx is rabbits. To control rabbit numbers, myxomatosis virus was released in Spain. This virus kills rabbits. Explain how this may have caused the lynx population to change. … … … [2]

7 0608/03/M/J/09 © UCLES 2009 [Turn over For Examiner’s Use (c) Much of the lynx’s habitat is being cleared so that the land can be used for housing and roads. Suggest what effects this is likely to have on the Iberian Lynx. Put ticks (✓) in the boxes next to the three best answers. More lynx will be killed on the roads. The lynx may become extinct. The population of the lynx will decrease. The population of the lynx will increase. There will be more habitats for the lynx. [2] [Total: 6]

8 0608/03/M/J/09 © UCLES 2009 For Examiner’s Use 4 The burning of fuels in motor vehicles releases small particulates of solids into the air. These particulates may irritate the lungs and cause problems for those suffering from asthma. Scientists measure the mass of solid particulates in the air in the centre of three different cities A, B and C. They make these measurements at the same time in each city. Their results are shown in the table. solid particulates (micrograms per cubic metre) Monday Tuesday Wednesday Thursday Friday mean city A 13 15 11 27 11 12 city B 39 36 35 38 37 city C 78 75 74 73 75 75 (a) A measurement of solid particulates higher than 50 micrograms per cubic metre is considered harmful to humans. In which city is the air harmful? city … [1] (b) The scientists decide that taking several measurements in each city gives a better estimate of the mass of solid particulates. Explain why repeated measurements are likely to give a better estimate. … … … [2] (c) The scientists calculate the mean (average) for the set of results for each city. (i) When calculating the mean for city A, they do not use the value for Thursday. Suggest why they do not use this value. … … [1] (ii) Work out the mean (average) for the measurements taken in city B. mean (average) = … micrograms per cubic metre [2]

9 0608/03/M/J/09 © UCLES 2009 [Turn over For Examiner’s Use (d) The table shows the average number of patients per day admitted to hospital because of an asthma attack. city A city B city C number of patients per day 78 105 147 The data suggests a correlation between mass of solid particulates and asthma attacks. Complete the sentence describing this correlation. Choose from this list. decreases increases stays the same As the mass of solid particulates in the air increases, the number of patients with asthma attacks ……………………………………………… . [1] (e) Solid particulates do not remain in the air for long. State what happens to them. … … [1] [Total: 8]

10 0608/03/M/J/09 © UCLES 2009 For Examiner’s Use 5 Crude oil is a mixture of hydrocarbons. (a) Which elements are present in hydrocarbons? Put a ring around each of the two correct elements. argon carbon hydrogen nitrogen oxygen [2] (b) Methane is a hydrocarbon found in crude oil. When methane burns completely in oxygen, it produces carbon dioxide and water. Look at this unfinished diagram for the complete burning of methane. + + methane (i) On the diagram, draw a ring around one molecule of oxygen. [1] (ii) Which of these needs to be added to finish the diagram? Put a tick (✓) in the box next to the correct answer. [1]

11 0608/03/M/J/09 © UCLES 2009 [Turn over For Examiner’s Use (c) Some of the hydrocarbons from crude oil are used to make polymers. (i) What is the name of this process? Put a ring around the correct answer. distillation oxidation photosynthesis polymerisation transpiration [1] (ii) Describe what happens during the process. … … … [2] [Total: 7]

12 0608/03/M/J/09 © UCLES 2009 For Examiner’s Use 6 Most processed foods contain chemicals that are added during processing. (a) Different additives are used for different reasons. Draw a line from each additive to the correct reason for adding it to food. additive reason antioxidant mix together ingredients that would normally separate emulsifier make the food taste better flavouring prevent the growth of harmful microbes preservative prevent fats and oils going off [3] (b) Some additives are harmful if their concentration in food is too high. How do scientific advisory committees in countries around the world make sure that additives do not cause harm? … … … [2] [Total: 5]

14 0608/03/M/J/09 © UCLES 2009 For Examiner’s Use 7 This question is about galaxies. Until the 1920s, scientists did not know what galaxies are. (a) Write down what galaxies are. … … … [2] (b) The astronomer Edwin Hubble first measured the speeds of distant galaxies. He found evidence for how the Universe began. (i) Describe what Hubble found about the movement of distant galaxies. … … [1] (ii) Scientists have used Hubble’s discoveries to find the age of the Universe. How old did they estimate it to be? Put a ring around the best answer in this list. 6000 years 6 million years 5000 million years 14 000 million years [1]

15 0608/03/M/J/09 © UCLES 2009 [Turn over For Examiner’s Use (c) Hubble’s explanation of the beginning of the Universe was not accepted by other scientists at the time. Suggest why it took some time for this new scientific explanation to be accepted. … … … [2] [Total: 6]

16 0608/03/M/J/09 © UCLES 2009 For Examiner’s Use 8 Most scientists now agree that global warming is a result of man-made activities. (a) Global warming is caused by greenhouse gases. One greenhouse gas is produced by burning fuel. Name this greenhouse gas. … [1] (b) Look at the graph showing how the Earth’s surface temperature has changed since 1850. Values are compared with a recent average, which is an average for the years 1961 – 1990. +0.6 +0.4 +0.2 0 –0.2 –0.4 –0.6 1860 1880 1900 1920 date 1940 1960 1980 2000 temperature difference (°C) compared with recent average (i) Use the graph to find the date at which the temperature was at its lowest value in the years shown in the graph. date = … [1] (ii) Use the graph to find the date at which the temperature was 0.4 °C above the recent average. date = … [1] (iii) Explain how the graph supports the view that global warming is taking place. … [1]

17 0608/03/M/J/09 © UCLES 2009 [Turn over For Examiner’s Use (c) Here are three different scientists’ opinions about global warming. Dr Agassi The temperature of the Earth is definitely going up. So is the amount of greenhouse gas in the atmosphere. The global warming must be due to the greenhouse gas. Dr Burger I don’t think that global warming is definitely taking place. We do not have enough data to be certain. The results only go back 160 years. Dr Chang I agree that the temperature of the Earth is increasing, but I don’t think it has anything to do with greenhouse gases. It’s just chance that they are both increasing. (i) Which scientists believe that global warming is taking place? Write each of their names in the space below. … [1] (ii) Which two scientists mention ideas of correlation and cause? … and … [1] (iii) Which one scientist talks about the difference between correlation and cause? … [1] [Total: 7]

18 0608/03/M/J/09 © UCLES 2009 For Examiner’s Use 9 This question is about generating electricity by nuclear power. (a) The block diagram shows a nuclear power station. Label the generator, reactor and turbine on the dotted lines provided. transformer electrical supply … … … [1] (b) The following energy flow diagram is for a modern nuclear power station generating electricity. 50 MJ in nuclear fuel 5 MJ left in nuclear fuel after use 25 MJ cooling steam electrical energy output Write down the amount of energy transferred into electrical energy output. electrical energy output = … MJ [1]

19 0608/03/M/J/09 © UCLES 2009 For Examiner’s Use (c) Workers at nuclear power stations are exposed to ionising radiation. This means that they have more risk than people who do not work with ionising radiation. (i) Write down what ionising radiation can do to cells. … … [1] (ii) Suggest two reasons why nuclear power station workers may be prepared to accept the risks of working at a nuclear power station. 1 … … 2 … … [2] (d) Because power station workers are exposed to risk of radiation, the power station managers must make sure that they do not get too large a dose. Describe two ways they could make sure that the workers do not get too large a dose. 1 … … 2 … … [2] [Total: 7]

20 0608/03/M/J/09 Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity. University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge. BLANK PAGE

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education MARK SCHEME for the May/June 2009 question paper for the guidance of teachers 0608 21ST CENTURY SCIENCE 0608/03 Paper 3 (Core Written), maximum raw mark 60 This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. It shows the basis on which Examiners were instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners’ meeting before marking began, which would have considered the acceptability of alternative answers. Mark schemes must be read in conjunction with the question papers and the report on the examination. • CIE will not enter into discussions or correspondence in connection with these mark schemes. CIE is publishing the mark schemes for the May/June 2009 question papers for most IGCSE, GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level syllabuses. www.XtremePapers.com

Page 2 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – May/June 2009 0608 03 © UCLES 2009 Key to abbreviations ecf error carried forward owtte or words to that effect Question Expected Answers Mks Additional Guidance 1 (a) nucleus; [1] (b) DNA proteins alleles recessive [3] 4 correct = (3) 3 correct = (2) 2 correct = (1) (c) (i) Father genotype (F)f (1); Correct offspring shown i.e. FF Ff Ff ff (1); [2] ecf from incorrect Henry genotype (ii) ff; [1] (d) (i) Adelina and Carlos [1] (ii) Bay [1] [Total: 9]

Page 3 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – May/June 2009 0608 03 © UCLES 2009 Question Expected Answers Mks Additional Guidance 2 (a) cycle to work
eat more fresh fruit
eat more full fat increase alcohol move away from stop smoking
[2] 3 correct = 2 marks 2 correct = 1 mark 1 correct = 0 marks (b) (i) [1] Within range shown (template to be issued) (ii) 130 to 150 [1] ecf from line (c) friends public scientists
politicians [1] [Total: 5]

Page 4 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – May/June 2009 0608 03 © UCLES 2009 Question Expected Answers Mks Additional Guidance 3 (a) (i) decreased/went down/dropped [1] owtte (ii) 680 [1] (b) rabbits are main food/prey of lynx (1); rabbit population decreases/rabbits killed by virus (1); so less food for lynx (1); [2] Any two points (c) More lynx ... roads.
The lynx ... extinct.
The population ... decrease
The population ... increase. There will be more habitats… [2] 3 correct = 2 marks 2 correct = 1 mark 1 correct = 0 marks [Total: 6] Question Expected Answers Mks Additional Guidance 4 (a) C [1] (b)* gives a more reliable estimate; can be used to calculate a mean/average; can rule out outliers/anomalies; one measurement could be a mistake [2] Any two (c) (i) it is an outlier/it is an anomaly/it is far different from the other measurements [1] (ii) 185/5 (1); = 37 (1) [2] (d) increases [1] (e)* they are deposited on surfaces/buildings [1] [Total: 8]

Page 5 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – May/June 2009 0608 03 © UCLES 2009 Question Expected Answers Mks Additional Guidance 5 (a) carbon (1); hydrogen (1) [2] one mark lost for each choice above two (b) (i) ring around one oxygen molecule only (1) [1] reject: ring around both oxygen molecules/any other molecules (ii) tick in third box (1) [1] reject: more than one box ticked (c) (i) polymerisation [1] reject: more than one ringed (ii)* small molecules join together (1); to form large molecules (1) [2] accept clear labelled diagram [Total: 7] Question Expected Answers Mks Additional Guidance 6 (a) [3] All correct (3); 2 correct (2); 1 correct (1) ignore any box with more than one line (b)* carry out risk assessments (1); determine safe levels of additives in food (1) [2] [Total: 5]

Page 6 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – May/June 2009 0608 03 © UCLES 2009 Question Expected Answers Mks Additional Guidance 7 (a) Made up of stars (1); Very great numbers of them (1) [2] Accept also gas and dust (1) Accept ‘millions’ or any word suggesting very large numbers (b) (i) Moving away (from us) (1) [1] (ii) 14 000 million years [1] (c) Previous theories had worked well for a long time (1); no- one else had produced this explanation yet (1); idea was too new and unexpected (1) [2] Any two points or one point plus a development [Total: 6] Question Expected Answers Mks Additional Guidance 8 (a) Carbon dioxide (1) [1] (b) (i) 1910 (1) [1] (ii) 2000 (1) [1] (iii) Trend of graph is upwards (1) [1] (c) (i) Dr Agassi and Dr Chang (1) [1] (ii) Dr Agassi and Dr Chang (1) [1] (iii) Dr Chang (1) [1] [Total: 7]

Page 7 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – May/June 2009 0608 03 © UCLES 2009 Question Expected Answers Mks Additional Guidance 9 (a) turbine generator reactor [1] (b) 20 MJ (1) [1] (c) (i) Kill/make cancerous (1) [1] (ii) Pay is good (1); no alternative employment (1); risk small (1); good working conditions (1) [2] Any two points (d) Have regular check-ups (1); Wear dosimeters/film badges (1)/protective clothing (1)/ shielding between worker and source of radiation (1)/ remote working to keep away from source of radiation (1) [2] Any two points [Total: 7]