AQA GCSE Biology Past Paper PDF (15 May 2018)

Please write clearly in block capitals. Centre number Candidate number Surname Forename(s) Candidate signature GCSE BIOLOGY Higher Tier Paper 1H...

Please write clearly in block capitals. Centre number Candidate number Surname Forename(s) Candidate signature GCSE BIOLOGY Higher Tier Paper 1H H Tuesday 15 May 2018 Afternoon Time allowed: 1 hour 45 minutes Materials For Examiner’s Use For this paper you must have: Question Mark a ruler 1 a scientific calculator. 2 Instructions 3 Use black ink or black ball-point pen. 4 Fill in the boxes at the top of this page. Answer all questions in the spaces provided. 5 Do all rough work in this book. Cross through any work you do not want 6 to be marked. 7 In all calculations, show clearly how you work out your answer. TOTAL Information There are 100 marks available on this paper. 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. *JUN1884611H01* IB/M/Jun18/E10 8461/1H  2 Do not write outside the box There are no questions printed on this page DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED *02* IB/M/Jun18/8461/1H  3 Do not write outside the 0 1 Eating food containing Salmonella bacteria can cause illness. box 0 1. 1 Two symptoms of infection by Salmonella are vomiting and diarrhoea. What causes these symptoms? [1 mark] 0 1. 2 Give two ways a person with a mild infection of Salmonella can help prevent the spread of the bacteria to other people. [2 marks] 1 2 0 1. 3 In very serious infections of Salmonella, a doctor can prescribe drugs to kill the bacteria. What type of drug can the doctor prescribe to kill the bacteria? [1 mark] 0 1. 4 A person with AIDS may take longer than a healthy person to recover from a Salmonella infection. Explain why. [2 marks] Turn over ► *03* IB/M/Jun18/8461/1H  4 Do not write outside the 0 1. 5 Salmonella bacteria can be transmitted from chickens to humans. Chickens can be box vaccinated to prevent the transmission of Salmonella bacteria to humans. Suggest one other way farmers could prevent the transmission of Salmonella from chickens to humans. [1 mark] A restaurant owner employed a scientist to test the effectiveness of two kitchen cleaning liquids. The scientist took samples from two work surfaces: before the surfaces had been cleaned with the cleaning liquids after the surfaces had been cleaned with the cleaning liquids. The samples were then analysed for the number of bacteria they contained. The results are shown in Figure 1. Figure 1 *04* IB/M/Jun18/8461/1H  5 Do not write outside the 0 1. 6 Which cleaning liquid is the more effective? box Give a reason for your answer. [1 mark] Cleaning Liquid Reason Question 1 continues on the next page Turn over ► *05* IB/M/Jun18/8461/1H  6 Do not write outside the The scientist investigated the effect of cleaning liquid A and cleaning liquid B on box Salmonella bacteria grown in a laboratory. Figure 2 shows the way the investigation was set up. Figure 2 The Petri dish was placed in an incubator at 25 °C for 48 hours. After 48 hours, the scientist calculated the area around each paper disc where no bacteria were growing. The results are shown in Table 1. Table 1 Area around disc with no Filter paper disc bacteria growing in cm2 Water 0 Cleaning liquid A 11 Cleaning liquid B 13 0 1. 7 What measurement would the scientist need to take to calculate the area where no bacteria were growing? [1 mark] *06* IB/M/Jun18/8461/1H  7 Do not write outside the 0 1. 8 Give one change to the investigation that would allow the scientist to check if the box results are repeatable. [1 mark] 0 1. 9 The scientist showed the results to the restaurant owner. Both cleaning liquids cost the same per dm3. Suggest one other factor the restaurant owner should consider when choosing which cleaning liquid to use. [1 mark] 11 Turn over for the next question Turn over ► *07* IB/M/Jun18/8461/1H  8 Do not write outside the 0 2 Metabolism is the sum of all the chemical reactions in the cells of the body. box One metabolic reaction is the formation of lipids. 0 2. 1 Give one other metabolic reaction in cells. [1 mark] Table 2 shows the mean metabolic rate of humans of different ages. Table 2 Age in Mean metabolic rate in kJ/m2/hour years Males Females 5 53 53 15 45 42 25 39 35 35 37 35 45 36 35 0 2. 2 What two conclusions can be made from the data in Table 2? [2 marks] Tick two boxes. As age increases, mean metabolic rate of males and females increases. Males have a higher metabolic rate than females after five years of age. The mean metabolic rate of females decreases faster than males up to 25 years of age. The mean metabolic rate of males and females decreases more quickly after the age of 35. There is no relationship between age and mean metabolic rate. *08* IB/M/Jun18/8461/1H  9 Do not write outside the 0 2. 3 Calculate the percentage decrease in the mean metabolic rate of males between box 5 years and 45 years of age. Use the equation: decrease in metabolic rate percentage decrease= × 100 original metabolic rate Give your answer to 3 significant figures. [3 marks] Percentage decrease = Question 2 continues on the next page Turn over ► *09* IB/M/Jun18/8461/1H  10 Do not write outside the Regular exercise can increase metabolic rate. box Two people did five minutes of gentle exercise from rest. Table 3 shows the effect of the exercise on their heart rates. Table 3 Time in Heart rate in beats per minute minutes Person R Person S 0 (at rest) 60 78 1 76 100 2 85 110 3 91 119 4 99 129 5 99 132 0 2. 4 Describe two differences in the response of person R and person S to the exercise. Use information from Table 3. [2 marks] 1 2 0 2. 5 Complete the line graph in Figure 3 for person S. You should: add the scale to the x axis label the x axis. [4 marks] *10* IB/M/Jun18/8461/1H  11 Do not write outside the Figure 3 box 0 2. 6 After five minutes of exercise, the heart rate of person S was 132 beats per minute. When person S rested, his heart rate decreased steadily at a rate of 12 beats every minute. Calculate how much time it would take the heart rate of person S to return to its resting rate. [2 marks] Time = minutes Turn over ► *11* IB/M/Jun18/8461/1H  12 Do not write outside the 0 2. 7 A student made the following hypothesis about the heart rate of smokers and box non-smokers during exercise. “During exercise, the heart rate of smokers increases more than the heart rate of non-smokers.” Design an investigation that would allow you to test this hypothesis. [6 marks] 20 *12* IB/M/Jun18/8461/1H  13 Do not write outside the 0 3 The circulatory system is composed of the blood, blood vessels and the heart. box 0 3. 1 Urea is transported in the blood plasma. Name two other substances transported in the blood plasma. [2 marks] 1 2 0 3. 2 Some athletes train at high altitude. Training at high altitude increases the number of red blood cells per cm3 of blood. Explain why having more red blood cells per cm3 of blood is an advantage to an athlete. [3 marks] 0 3. 3 Which two blood vessels carry deoxygenated blood? [2 marks] Tick two boxes. Aorta Coronary artery Pulmonary artery Pulmonary vein Vena cava Turn over ► *13* IB/M/Jun18/8461/1H  14 Do not write outside the Figure 4 shows the three types of blood vessel. box Figure 4 0 3. 4 Which type of blood vessel carries blood into the right atrium? [1 mark] Tick one box. A B C 0 3. 5 Compare the structure of an artery with the structure of a vein. [3 marks] *14* IB/M/Jun18/8461/1H  15 Do not write outside the 0 3. 6 Heart rate is controlled by a group of cells. This group of cells act as a pacemaker. box Figure 5 shows a section through the heart. Draw an X on Figure 5 to show the position of the pacemaker. [1 mark] Figure 5 0 3. 7 A patient may be fitted with an artificial pacemaker. What condition may be treated using an artificial pacemaker? [1 mark] 13 Turn over ► *15* IB/M/Jun18/8461/1H  16 Do not write outside the 0 4 A student carried out an investigation using chicken eggs. box This is the method used. 1. Place 5 eggs in acid for 24 hours to dissolve the egg shell. 2. Measure and record the mass of each egg. 3. Place each egg into a separate beaker containing 200 cm3 of distilled water. 4. After 20 minutes, remove the eggs from the beakers and dry them gently with a paper towel. 5. Measure and record the mass of each egg. Table 4 shows the results. Table 4 Mass of egg without shell Mass of egg after 20 Egg in grams minutes in grams 1 73.5 77.0 2 70.3 73.9 3 72.4 75.7 4 71.6 73.1 5 70.5 73.8 0 4. 1 Another student suggested that the result for egg 4 was anomalous. Do you agree with the student? Give a reason for your answer. [1 mark] *16* IB/M/Jun18/8461/1H  17 Do not write outside the 0 4. 2 Calculate the percentage change in mass of egg 3. box [2 marks] Percentage change in mass = 0 4. 3 Explain why the masses of the eggs increased. [3 marks] 0 4. 4 Explain how the student could modify the investigation to determine the concentration of the solution inside each egg. [3 marks] Turn over ► *17* IB/M/Jun18/8461/1H  18 Do not write outside the Chicken egg shells contain calcium. Calcium ions are moved from the shell into the box cytoplasm of the egg. Table 5 shows information about the concentration of calcium ions. Table 5 Concentration of calcium Location ions in arbitrary units Egg shell 0.6 Egg cytoplasm 2.1 0 4. 5 Explain how calcium ions are moved from the shell into the cytoplasm of the egg. [3 marks] 12 *18* IB/M/Jun18/8461/1H  19 Do not write outside the 0 5 Plants can be infected by fungi, viruses and insects. box Aphids are small insects that carry pathogens. Figure 6 shows an aphid feeding from a plant stem. Figure 6 0 5. 1 An aphid feeds by inserting its sharp mouthpiece into the stem of a plant. Give the reason why the mouthpiece of an aphid contains a high concentration of dissolved sugars after feeding. [1 mark] Question 5 continues on the next page Turn over ► *19* IB/M/Jun18/8461/1H  20 Do not write outside the 0 5. 2 Plants infected with aphids may show symptoms of magnesium deficiency. box Magnesium deficiency symptoms include: yellow leaves stunted growth. Explain how a deficiency of magnesium could cause these symptoms. [5 marks] *20* IB/M/Jun18/8461/1H  21 Do not write outside the 0 5. 3 A farmer thinks a potato crop is infected with potato virus Y (PVY). box The farmer obtains a monoclonal antibody test kit for PVY. To make the monoclonal antibodies a scientist first isolates the PVY protein from the virus. Describe how the scientist would use the protein to produce the PVY monoclonal antibody. [4 marks] 10 Turn over ► *21* IB/M/Jun18/8461/1H  22 Do not write outside the Following updated research information and communications with parents of children with box cystic fibrosis, we have decided to withdraw the question on this topic from this paper. It has been decided not to provide a replacement question as it would not be possible to determine accurately how a replacement question would have performed if it had been part of the original paper taken in 2018. The following statistics may help you to make effective use of the remainder of the paper: Mean mark (maximum mark) 06.1 0.47 (1) 06.2 0.65 (1) 06.3 2.27 (6) 06.4 1.27 (2) 06.5 0.69 (1) 06.6 1.33 (2) 06.7 0.56 (4) 06.8 0.42 (1) Question 6 7.66 (18) *22* IB/M/Jun18/8461/1H  23 Do not write outside the Turn over for the next question box DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED Turn over ► *23* IB/M/Jun18/8461/1H  24 Do not write outside the 0 7 Table 8 shows information about some food components in cow’s milk. box Table 8 Recommended Daily Value per Allowance (RDA) 500 cm3 for a typical adult Energy in kJ 1046 8700 Fat in g 8.4 70.0 Salt in g 0.5 6.0 Calcium in mg 605 1000 Vitamin B-12 in µg 4.5 2.4 0 7. 1 How much more milk would a typical adult have to drink to get their RDA for calcium compared with the amount of milk needed to get their RDA for vitamin B-12? [3 marks] Volume of milk = cm3 *24* IB/M/Jun18/8461/1H  25 Do not write outside the 0 7. 2 Describe how a student could test cow’s milk to show whether it contains protein and box different types of carbohydrate. [6 marks] Question 7 continues on the next page Turn over ► *25* IB/M/Jun18/8461/1H  26 Do not write outside the A scientist investigated the effect of bile on the breakdown of fat in a sample of milk. box The scientist used an indicator that is colourless in solutions with a pH lower than 10, and pink in solutions with a pH above 10. This is the method used. 1. Add 1 drop of bile to a test tube and one drop of water to a second test tube. 2. Add the following to each test tube: 5 cm3 of milk 7 cm3 of sodium carbonate solution (to make the solution above pH 10) 5 drops of the indicator 1 cm3 of lipase. 3. Time how long it takes for the indicator in the solutions to become colourless. The results are shown in Table 9. Table 9 Time taken for the indicator to become colourless in seconds Solution with bile 65 Solution without bile 143 0 7. 3 Explain why the indicator in both tubes became colourless. [3 marks] *26* IB/M/Jun18/8461/1H  27 Do not write outside the 0 7. 4 Give the reason why the measurement of the time taken for the indicator to become box colourless might be inaccurate. [1 mark] 0 7. 5 Explain the difference in the results for the two test tubes in Table 9. [3 marks] 16 END OF QUESTIONS *27* IB/M/Jun18/8461/1H  28 Do not write outside the box There are no questions printed on this page DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED Copyright information For confidentiality purposes, from the November 2015 examination series, acknowledgements of third party copyright material will be published in a separate booklet rather than including them on the examination paper or support materials. This booklet is published after each examination series and is available for free download from www.aqa.org.uk after the live examination series. 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. Copyright © 2018 AQA and its licensors. All rights reserved. *28* IB/M/Jun18/8461/1H