Cambridge IGCSE Twenty-First Century Science 0608 — 2011 Oct/Nov Paper 3 · Variant 1

This document consists of 15 printed pages and 1 blank page. DC (NF/CGW) 35864/2 © UCLES 2011 [Turn over UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education * 8 7 3 7 6 7 2 3 1 8 * TWENTY FIRST CENTURY SCIENCE 0608/03 Paper 3 October/November 2011 1 hour 30 minutes Candidates answer on the Question Paper. No Additional Materials are required. 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. For Examiner’s Use 1 2 3 4 5 6 7 8 9 Total www.XtremePapers.com

2 0608/03/O/N/11 © UCLES 2011 For Examiner’s Use 1 Methane, CH4, is a fuel. It is burned to release heat energy. In a plentiful supply of oxygen, O2, methane burns to produce carbon dioxide, CO2, and water, H2O, only. Look at this diagram showing the burning of one molecule of methane. methane oxygen + + carbon dioxide water (a) Complete this table to show the number of molecules in the reactants and products when one molecule of methane burns. reactants products methane oxygen carbon dioxide water number of molecules 1 2 [2] (b) Complete this table to show the number of atoms of each element in the reactants and products when one molecule of methane burns. carbon hydrogen oxygen number of atoms in reactants 1 number of atoms in products 1 [2] (c) When methane burns in a limited supply of air, other products are also formed. These other products cause air pollution. Name one of these other products. … [1] [Total: 5]

3 0608/03/O/N/11 © UCLES 2011 [Turn over For Examiner’s Use 2 Most window frames are made from either wood or unplasticised polyvinylchloride (uPVC). Data from a Life Cycle Assessment (LCA) for window frames, of the same size, made from each of these two materials are shown in the table. part of LCA wood uPVC energy for production, use and disposal 9150 MJ 9713 MJ fossil fuel used 5.57 kg 18.23 kg carbon dioxide produced 457 kg 487 kg smog chemicals 893 383 air acidification 29.6 37.7 water pollution 67 1.6 (a) For which parts of the LCA is wood a more sustainable material for a window frame than uPVC? Choose your answers by ticking the correct boxes. tick (✓) energy for production, use and disposal fossil fuel used carbon dioxide produced smog chemicals air acidification water pollution [3] (b) Complete the sentences about the sustainability of wooden and uPVC window frames. Use words from this list. burned more less grown oil wood Wood used to make window frames comes from trees. More trees can be … . uPVC is made from chemicals in crude … . This will one day run out. Wooden window frames are therefore made from a … sustainable material than uPVC window frames. [2]

4 0608/03/O/N/11 © UCLES 2011 For Examiner’s Use (c) uPVC does not contain a plasticiser. Explain why PVC containing a plasticiser would not be a good material for a window frame. … … … [2] (d) The main cause of air acidification is the release of acidic gases from burning fossil fuels. Acid rain is formed from these acidic gases. (i) Give the name and formula of one of the gases that cause acid rain. name … formula … [2] (ii) Describe one environmental problem caused by acid rain. … … [1] [Total: 10]

5 0608/03/O/N/11 © UCLES 2011 [Turn over For Examiner’s Use 3 Country A is an industrialised country. Farmers in country A use synthetic pesticides to prevent insect pests attacking their crops. They spread synthetic fertilisers on their fields. Country B is a developing country. Farmers in country B use organic farming methods. They do not use synthetic pesticides or synthetic fertilisers. (a) (i) Suggest why farmers in country B do not use pesticides. … … [1] (ii) Describe one method that farmers in country B may use to protect their crops from insect pests. … … [1] (iii) How may farmers in country B be affected by the fact that they do not use pesticides? … … [1] (b) When crops are grown they take nitrogen compounds from the soil. Farmers put fertiliser on their fields to add nitrogen compounds to the soil. (i) A farmer grows crops for several years without adding fertiliser to the soil. Describe what happens to his crops. … … [1] (ii) Farmers in country B do not use synthetic fertilisers. Suggest how they add nitrogen compounds to their soil. … … [1] [Total: 5]

6 0608/03/O/N/11 © UCLES 2011 For Examiner’s Use 4 This question is about the movement of the Earth’s tectonic plates. (a) Although Wegener’s idea of continental drift was first suggested in 1912, it was more than 50 years before geologists believed this. Use words from the list to explain why they did not believe this in 1912. astronomy chemistry earthquakes evidence geology movement It was not possible to detect any … of the continents. There was not enough … to support Wegener’s ideas. Scientists did not think Wegener had enough knowledge because he had no training in … [3] (b) The movement of the tectonic plates is due to movements inside the Earth. Write down the name of the part of the Earth causing the movement of tectonic plates. … [1]

7 0608/03/O/N/11 © UCLES 2011 [Turn over For Examiner’s Use (c) The Earth’s tectonic plates in the Indian Ocean region are shown in the diagram. The pairs of arrows A, B, C, D, E and F show the directions of movement of the plates. A B C D E F land key sea (i) The letters B and C show places where sea-floor spreading is taking place. Which other letter, A, D, E or F, also shows a place where sea-floor spreading is taking place? … [1] (ii) Which one of the movements, A, B, C, D, E or F, is opening a valley on the land? … [1] (iii) Which of the movements A, B, C, D, E and F are building mountains? Write down each of the letters. … [1] [Total: 7]

8 0608/03/O/N/11 © UCLES 2011 For Examiner’s Use 5 This question is about microwave radiation. (a) The table shows the electromagnetic spectrum. (i) Fill in the missing names. radio waves … infrared visible light … … gamma rays [2] (ii) In the table, put a tick (✓) next to the name of each ionising radiation. [1] (b) Some people believe that microwaves from mobile phones may be a health risk, but they still use mobile phones. Suggest why they use mobile phones, even though there is a risk. Use ideas of risk and benefit in your answer. … … … … [2] (c) Microwave ovens are much more powerful than mobile phones, but they are not thought to be dangerous. Explain how the construction of microwave ovens protects users from microwave radiation. … … [1] [Total: 6]

9 0608/03/O/N/11 © UCLES 2011 [Turn over For Examiner’s Use 6 This question is about generating electricity from biomass (waste vegetable matter). (a) Burning biomass to generate electricity is an example of a renewable energy source. (i) Give one other example of a renewable energy source. … [1] (ii) Burning biomass is renewable because the vegetable matter can be grown as fast as it is burned. Explain why burning coal is not renewable. … … [1]

10 0608/03/O/N/11 © UCLES 2011 For Examiner’s Use (b) The following energy flow diagram shows the energy obtained from burning 25 kg of biomass. The energy is measured in megajoules (MJ). waste heat 60 MJ electrical energy produced heat energy in steam used in factory 200 MJ total energy released by burning 25 kg biomass 400 MJ (i) How much energy does 25 kg of biomass release? energy = … MJ [1] (ii) How does the diagram show that half of the energy in the biomass is transferred into heat energy in steam? … [1] (iii) Explain how the energy flow diagram shows that 140 MJ of electrical energy were produced. … … [1] (iv) Use the equation efficiency = useful output energy × 100 total input energy % to calculate the efficiency of production of electrical energy. Show your working. efficiency = …% [2] [Total: 7]

11 0608/03/O/N/11 © UCLES 2011 [Turn over For Examiner’s Use 7 (a) Some cells are unspecialised and can develop into many other types of cell. What name is given to these unspecialised cells? … [1] (b) Complete the sentences, choosing the correct words from the list below. embryos harmful nerve people unnatural unspecialised There is the potential to use … cells to treat some illnesses. It is possible to clone … to produce large numbers of unspecialised cells. Some people think this should never be done because it is … . [3] (c) Read the sentences in the box. A Scientists have discovered that baby teeth are a source of unspecialised cells. B Storing your children’s baby teeth could help to save their lives in the future. C The unspecialised cells are easy and painless to extract. D Storing the teeth is very expensive. E There is no guarantee unspecialised cells will be able to help cure diseases. F Many teeth can be stored for each child. G It may not be possible to extract the unspecialised cells if the teeth are damaged. Which of the sentences, A, B, C, D, E, F and G, suggest reasons why (i) parents may choose to store their children’s baby teeth, … [1] (ii) parents may choose not to store their children’s baby teeth? … [1]

12 0608/03/O/N/11 © UCLES 2011 For Examiner’s Use (d) Read the following sentences about twins. In the box next to each sentence, write a T if the sentence is true or an F if the sentence is false. T or F identical twins are clones identical twins are produced asexually identical twins can appear different due to environmental factors identical twins occur when the cells of an embryo separate [2] [Total: 8]

13 0608/03/O/N/11 © UCLES 2011 [Turn over For Examiner’s Use 8 When Janet had a throat infection caused by bacteria the doctor gave her antibiotics. Janet is now suffering from influenza, which is caused by a virus. The doctor will not give her antibiotics for influenza. (a) Explain why the doctor gave Janet antibiotics for a throat infection but will not give her antibiotics for influenza. … … … [2] (b) John does not want to catch influenza. He goes to the doctor for a vaccination to help prevent him catching this disease. John had an influenza vaccination last year. (i) Explain why John needs to have a vaccination against influenza this year, even though he had one last year. … … [1] (ii) State the name of the chemicals that are produced in the body following a vaccination. … [1] (c) In 2009, there was an outbreak of influenza caused by a new microorganism called H1N1. This new type of influenza spread quickly around the world. Scientists developed a vaccine against H1N1 to help stop the spread of the disease. New vaccines must be tested before they can be used. Suggest why a new vaccine must be tested. … … … [1]

14 0608/03/O/N/11 © UCLES 2011 For Examiner’s Use (d) Abi is pregnant. Her doctor recommends that she should have the vaccination against H1N1. Abi is not sure whether she should have the vaccination or not. She talks to her friends and asks their opinions. The vaccine has been developed very quickly and has not been tested as thoroughly as other vaccines. The vaccination protects against H1N1 and does not cause any damage to the baby. When you are pregnant, your immune system is weakened and you are not able to fight off infections as easily. A C B D E It is important for a pregnant woman to make the right decision for both her and her baby. Having the vaccination really hurts and your arm can be very sore for a few days afterwards. Complete the table by writing the letters A, B, C, D and E in the correct columns. Each letter can be used once only. friends who give reasons to have the vaccination friends who give reasons not to have the vaccination friends whose comments do not support either argument [2] [Total: 7]

15 0608/03/O/N/11 © UCLES 2011 For Examiner’s Use 9 Look at the flow diagram. This shows an example of nervous communication. A hot object B skin C brain and spinal cord D muscles E hand pulled away (a) Which one of the boxes, A, B, C, D or E, represents (i) the central nervous system, … [1] (ii) the stimulus, … [1] (iii) the effector cells, … [1] (iv) the sensor (receptor) cells? … [1] (b) Communication can be hormonal as well as nervous. Give one example of hormonal communication. … … [1] [Total: 5]

16 0608/03/O/N/11 © UCLES 2011 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 October/November 2011 question paper for the guidance of teachers 0608 TWENTY FIRST 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. • Cambridge will not enter into discussions or correspondence in connection with these mark schemes. Cambridge is publishing the mark schemes for the October/November 2011 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 – October/November 2011 0608 03 © University of Cambridge International Examinations 2011 1 (a) 1 2 [2] one mark for each correct number (b) 4 4 4 4 [2] one mark for each correct row (left to right) allow one mark if first row incorrect but repeated in second row (c) carbon / carbon monoxide [1] Total [5] 2 (a) ticks in boxes 1, 2, 3 and 5 [3] all 4 correct boxes ticked = 3 marks 3 boxes = two marks 2 boxes = one mark 5 boxes ticked max 1 all 6 boxes ticked = 0 (b) grown oil more [2] 3 correct = 2 marks 2 correct = 1 mark (c) window frame would be too soft/floppy; glass may fall out [2] (d) (i) sulfur dioxide; SO2 / nitrogen dioxide NO2 [2] 1 mark for name, 1 mark for matching formula (ii) corrodes statues etc / acidifies lakes / kills fish / kills trees [1] Total [10] 3 (a) (i) too expensive / not available [1] (ii) pick off by hand / crop rotation / natural predators [1] (iii) reduced yield [1] (b) (i) yield reduces / crops do not grow well [1] (ii) manure / crop rotation / grow legumes [1] allow example of legume e.g. clover/beans/peas Total [5]

Page 3 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – October/November 2011 0608 03 © University of Cambridge International Examinations 2011 4 (a) movement (1); evidence(1); geology (1) [3] (b) mantle (1); [1] (c) (i) F [1] (ii) D [1] (iii) A and E [1] need both and no others Total [7] 5 (a) (i) microwave, ultraviolet, X-rays [2] all correct = 2 2 correct = 1 (ii) ticks in at least two of the three right-hand end boxes [1] any two of these and no tick for a non-ionising radiation for the mark accept any clear indication of choices. (b) risk is small/ not certain there is any risk (1); any named benefit, e.g. convenience, phone access in emergency, having the latest gadget, prestige (1) benefit is greater than the risk (1) [2] any two (c) metal walls/door screen reflect microwaves back into cavity [1] both metal and reflect (or block) needed Total [6] 6 (a) (i) wind / wave / hydroelectric / geothermal / tidal [1] any reasonable renewable source other than biomass (ii) coal once used is gone forever / cannot grow more coal (1); [1] (b) (i) 400 [1] (ii) 200MJ heat energy used in factory / arrow for use in factory is half the total width [1] (iii) 400 – 60 – 200 (MJ) = 140 (MJ) [1] any clear indication of process e.g. ‘It’s the input take away the steam and the waste’ (iv) 140 × 100/400 (1) = 35% (1) [2] full marks for correct answer without working Total [7]

Page 4 Mark Scheme: Teachers’ version Syllabus Paper IGCSE – October/November 2011 0608 03 © University of Cambridge International Examinations 2011 7 (a) stem cells [1] (b) unspecialised embryos unnatural [3] one mark for each correct word (c) (i) A B C F [1] any two (ii) D E G [1] any two (d) T F T T [2] all correct = 2 2/3 correct = 1 0/1 correct = 0 Total [8] 8 (a) influenza is caused by a virus; antibiotics kill bacteria / antibiotics cannot destroy viruses [2] (b) (i) ‘flu virus changes / mutates very quickly [1] (ii) antibodies [1] (c) to ensure it is safe / effective / has no (serious) side effects [1] (d) BC AE D [2] all 5 correct = 2 3 or 4 correct = 1 Total [7] 9 (a) (i) C [1] (ii) A [1] (iii) D [1] (iv) B [1] (b) lowering blood sugar levels after a meal / raising of heart beat when frightened [1] allow any valid example Total [5]