GCSE COMBINED SCIENCE SYNERGY

Transcription

1 Please write clearly in block capitals. Centre number Candidate number Surname Forename(s) Candidate signature GCSE COMBINED SCIENCE SYNERGY Foundation Tier Paper 1F F Specimen 2018 Time allowed: 1 hour 45 minutes Materials For this paper you must have: a ruler a scientific calculator the periodic table (enclosed) the Physics Equations Sheet (enclosed). Instructions Use black ink or black ball-point pen. Fill in the es at the top of this page. Answer all questions in the spaces provided. Do all rough work in this book. Cross through any work you do not want to be marked. In all calculations, show clearly how you work out your answer. Information The maximum mark for this paper is 100. The marks for questions are shown in brackets. You are expected to use a calculator where appropriate. You are reminded of the need for good English and clear presentation in your answers. For Examiner s Use Question Mark TOTAL IB/M/SAMs/E1 8465/1F

2 2 0 1 Figure 1 shows a reflex arc that moves the arm if the hand touches something hot. Figure Which part is the receptor? Tick one. A B D F Which part is the effector of the reflex action? Tick one. A B D F

3 Which part shows a sensory neurone? Tick one. B D E F Which part shows a synapse? Tick one. A B D E Part C contains DNA. Which part of the nerve cell is C? Tick one. Cell membrane Cytoplasm Mitochondrion Nucleus Question 1 continues on the next page Turn over

4 Reflex actions are automatic and do not involve thinking. Why is this an advantage? Which two factors can make you slower to react to a stimulus? Tick two es. Alcohol Caffeine Daylight Practice Tiredness 8

5 5 0 2 Respiration occurs in living cells Complete the word equation for aerobic respiration. [3 marks] + oxygen + Lactic acid is produced in muscles when there is insufficient oxygen for aerobic respiration Suggest how muscles feel when lactic acid levels increase. Question 2 continues on the next page Turn over

6 6 Scientists investigated the concentration of lactic acid in the blood of an athlete running at different speeds. This is the method used. 1. An athlete runs on a treadmill at a speed of 3.0 metres per second (m/s). 2. After 10 minutes her blood lactic acid concentration is recorded. 3. The athlete rests until her lactic acid concentration returns to normal. 4. She repeats the investigation at different speeds. The room was kept at 18 C. Figure 2 shows the scientists results. Figure 2

7 Give three control variables in this investigation. [3 marks] Describe the trend shown in Figure 2 between 3.5 m/s and 5.0 m/s Determine the change in lactic acid concentration in the blood between 3.5 m/s and 5.0 m/s Change in lactic acid concentration = arbitrary units Question 2 continues on the next page Turn over

8 As the speed increases the heart rate of the athlete increases. As the speed increases from 3.0 m/s to 3.4 m/s lactic acid concentration in the blood decreases. Explain how an increase in heart rate could cause the decrease in lactic acid concentration. [3 marks] Use words from the. blood flow muscle oxygen respiration After the athlete stops running, her heart rate and breathing rate do not immediately return to normal. Why does it take time for her heart rate and breathing rate to return to normal? Tick two es. After anaerobic respiration oxygen debt must be repaid. Carbon dioxide is not being produced. Increased breathing rate delivers more carbon dioxide to muscles. Increased heart rate delivers more glucose to muscles. Oxygen is needed to remove lactic acid from muscles. 16

9 9 Turn over for the next question DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED Turn over

10 Figure 3 shows how cells from human embryos can be used to grow replacement body parts for humans. Figure How many chromosomes are in a fertilised human egg? Tick one

11 What is the process labelled G? Tick one. Fertilisation Inheritance Meiosis Mitosis When the embryo is three days old, it contains eight cells. How many times has the fertilised egg cell divided by day three? Tick one Stem cells become specialised in the process labelled H in Figure 3. What is the process labelled H? Tick one. Differentiation Evolution Genetic modification Selective breeding Question 3 continues on the next page Turn over

12 Which two parts would be found in all the cells in Figure 3? Tick two es. Cell membrane Call wall Chloroplasts Cytoplasm Plasmids Why might stem cells from human embryos be more useful than stem cells from adults?

13 Some parents have stem cells from the umbilical cord of their baby collected and stored. These stem cells can be used to treat diseases in the child later in life. Why might stem cells from their own umbilical cord be used rather than stem cells from another embryo? Tick one. Less risk of rejection of umbilical cord stem cells. Stem cells from another embryo can treat more diseases. Umbilical cord stem cells are older Some medical uses of stem cells are still experimental. Why do some scientists have concerns about the use of stem cells? Some people object to the use of embryonic stem cells because of religious beliefs. Give one other ethical concern about the use of embryonic stem cells? 10 Turn over for the next question Turn over

14 Figure 4 shows a model of the particles in a gas and in a liquid. Figure Complete Figure 4 to show the arrangement of particles of the same substance as a solid What is the name of the process when a substance changes from a gas to a liquid? Tick one. Condensing Evaporating Freezing Melting

15 The substance in Figure 4 has a: melting point of 98 C boiling point of 883 C What is the state of the substance at 20 C? Tick one. Gas Liquid Solid What type of change is a change of state? Tick one. Chemical Kinetic Permanent Physical Question 4 continues on the next page Turn over

16 Which two statements are correct about the particles when a liquid turns into a gas? Tick two es. Particles are bigger Particles are lighter Particles have more chemical energy Particles have more kinetic energy Particles move faster Which two quantities are needed to calculate the energy required to turn a liquid into a gas with no change in temperature? You may use the Physics Equations Sheet. Tick two es. Mass of the liquid Specific heat capacity of the gas Specific latent heat of vaporisation Time the liquid is heated

17 A mass of 2.0 kg of water is heated. The temperature increase of the water is 80 C The specific heat capacity of water is 4200 J / kg C Calculate the change in thermal energy when the water is heated. Use the equation: change in thermal energy = mass specific heat capacity temperature change Change in thermal energy = J 11 Turn over for the next question Turn over

18 Table 1 shows the percentage of some gases in the atmosphere on Earth and on Venus. Table 1 Gas Percentage of gas in atmosphere Earth Venus Nitrogen Oxygen Carbon dioxide Give two differences in the atmosphere on Earth compared with the atmosphere on Venus Give a source of each of the gases below that are found in the Earth s atmosphere. Carbon dioxide Oxygen

19 Water moves between and Earth and its atmosphere. Describe how water enters and leaves the atmosphere. How water enters the atmosphere How water leaves the atmosphere The percentage of carbon dioxide in the Earth s atmosphere is increasing. What environmental problem is caused by the increased percentage of carbon dioxide in the atmosphere? Tick one. Deforestation Destruction of peat bogs Global warming Pollution of streams Suggest two negative impacts of climate change. 9 Turn over

20 Rose black spot is a disease that affects rose plants. The leaves of infected plants develop black spots, then turn yellow and drop off the plant Give the name of the substance in leaves that is broken down when leaves change from green to yellow Rose black spot can be transferred between plants in water droplets. Draw one line from each method of black spot prevention to the explanation of why that method works. Method Plant roses with large gaps between plants Explanation Fungus spores are removed Helps leaves dry faster Clear dead leaves Increases infection in warm weather Prevents rain falling on the leaves Fungicides can be sprayed on rose plants to prevent infection with black spot. Some fungicides appear to be less effective than they were 10 years ago. Suggest why the fungicides are less effective now compared with 10 years ago.

21 21 Some gardeners claim that rose black spot has become more of a problem since the Clean Air Act of Table 2 shows how the mass of sulfur dioxide (SO 2 ) emissions has changed. Table 2 Year Power stations SO 2 emissions from each source in megagrams Manufacturing industry Homes and transport Total SO 2 emissions in megagrams X The sulfur dioxide emissions in Table 2 are shown in megagrams. Calculate value X in Table 2. X = Mg Give your answer to Question 06.4 in kilograms. 1 megagram = 1000 kilograms Question 6 continues on the next page X = kg Turn over

22 How have power stations reduced their sulfur dioxide emissions? Tick one. Power stations used more at night than during the day Power stations generate more electricity Power stations use less coal Power stations use more oil A gardener concluded that the information in Table 2 shows the Clean Air Act of 1958 changed sulfur dioxide emissions Give one reason to support the conclusion Give one reason why the conclusion may not be valid.

23 Suggest how changing sulfur dioxide emissions increased the number of cases of rose black spot. 11 Turn over for the next question Turn over

24 The Arabian oryx (Oryx leucoryx) is a mammal that was once extinct in the wild. Figure 5 shows an Arabian oryx. Figure What is the genus of the Arabian oryx? Tick one. leucoryx Oryx Oryx leucoryx

25 Give two adaptations of the Arabian oryx to living in hot desert environments. Use information from Figure The Arabian oryx uses its long horns to fight for territory and mates. Describe how the long horns could have evolved. [3 marks] Question 7 continues on the next page Turn over

26 26 Arabian oryx from many different zoos were interbred so that they could be reintroduced to the wild What is the name of this method of increasing the population of endangered animals? Tick one. Breeding programme Genetic modification Natural selection Selective breeding Explain why it was important to use Arabian oryx from many different zoos instead of one zoo. 8

27 27 Turn over for the next question DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED Turn over

28 Figure 6 shows an image of blood viewed with a microscope Label Figure 6. [3 marks] Figure 6

29 The mean concentration of red blood cells in an adult is cells per mm 3 1 mm 3 = dm 3 Calculate the mean number of red blood cells in 1 dm 3 Give your answer in standard form. [3 marks] Mean number of red blood cells in 1 dm 3 = Calculate the number of red blood cells in an adult who has 5.2 dm 3 of blood. Use your answer from Question Number of red blood cells in an adult = Question 8 continues on the next page Turn over

30 30 Sickle cell disease is an inherited disorder that causes some red blood cells to have a sickle shape. Figure 7 shows two red blood cells. Figure A person only has sickle cell disease if two copies of the sickle cell allele are inherited. What does this tell us about the sickle cell allele?

31 Explain how the shape of the red blood cells in a person with sickle cell disease could affect how much oxygen reaches their muscles. [6 marks] Suggest one symptom of sickle cell disease. 15 Turn over for the next question Turn over

32 The arrangement of electrons in atoms can change Describe what might happen to make an electron move from a lower energy level to a higher energy level in a neon atom Describe what happens when an electron moves from a higher to a lower energy level in a neon atom.

33 Table 3 shows information about radiation doses. Table 3 Radiation dose in millisieverts Mean annual dose from natural sources 2.7 Mean dose from one aircraft flight The mean annual dose a person receives from natural sources is greater than the mean dose from one aircraft flight. Calculate how many times greater. Number of times greater = X-rays can be harmful. Suggest why some people think X-rays are more dangerous than they really are. Question 9 continues on the next page Turn over

34 Ionising radiation can be used to treat patients in hospital. People working in hospitals must limit their exposure to ionising radiation. Explain how the use of ionising radiation in hospitals can be both useful and harmful. [6 marks] 12 END OF QUESTIONS Copyright Information Permission to reproduce all copyright material has been applied for. In some cases, efforts to contact copyright-holders may have been unsuccessful and AQA will be happy to rectify any omissions of acknowledgements. If you have any queries please contact the Copyright Team, AQA, Stag Hill House, Guildford, GU2 7XJ. Acknowledgement of copyright holders and publishers Figure 5 istock.com/katiekk2 Copyright 2017 AQA and its licensors. All rights reserved.