2024 AQA GCSE COMBINED SCIENCE: SYNERGY 8465/2H Paper 2 Question Paper + Mark Scheme + Ins, Exams of Environmental Science

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2024 AQA GCSE COMBINED SCIENCE: SYNERGY 8465/2H Paper 2 Question Paper + Mark Scheme + Inserts AQA Please write clearly in block capitals. Centre number Candidate number Surname Forename(s) Candidate signature | declare this is my own work. GCSE COMBINED SCIENCE: SYNERGY Higher Tier Paper 2 Life and Environmental Sciences Wednesday 22 May 2024 Morning Time allowed: 1 hour 45 minutes Materials For this paper you must have: a ruler Question Mark a protractor 1 a scientific calculator the periodic table (enclosed) the Physics Equations Sheet (enclosed). For Examiner's Use Instructions e Use black ink or black ball-point pen. Pencil should only be used for drawing. Fill in the boxes at the top of this page. Answer all questions in the spaces provided. Do not write outside the box around each page or on blank pages. 8 If you need extra space for your answer(s), use the lined pages at the end of 2 - - i TOTAL this book. Write the question number against your answer(s). Do all rough work in this book. Cross through any work you do not want to be marked. e Inall calculations, show clearly how you work out your answer. Nl Ol) ala) wlrm Information e 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. N00 nese | Do not write outside the box Two students analysed water from four rivers. Each student measured the pH of the river water using a different method. Table 1 shows the results. Table 1 pH of river water River Method A Method B Ww 7 TA xX 6 6.5 Y 8 8.1 Z 7 76 [0 [1]-[1] Suggest what was used to measure the pH in each method. [2 marks] Method A Method B fo] 1].[2] Why is it not valid to calculate a mean of the two pH values for each river? [1 mark] Tick (“) one box. A mean cannot be calculated from only two values. Each method gives values to a different resolution. The mean should be calculated for each method using all four samples. IML G/Jun24/8465/2H 2 Do not write outside the box [0 | 1]-[6] Describe a method to determine the mass of dissolved solids in 50 cm3 of river water. [4 marks] 12 MMT G/Jun24/8465/2H 4 Do not write outside the box Turn over for the next question DO NOT WRITE/ON THIS PAGE ANSWER IN THE/SPACES PROVIDED Turn over > AMM G/Jun24/8465/2H 5 Do not write outside the box The student used quadrats to randomly sample the biodiversity of plants in: e the area with living grass e the area with plastic grass. Describe how the student could decide where to randomly place the quadrats in the area with plastic grass. [2 marks] -[2] How would a greater number of different plant species affect the biodiversity of animals in the area? [1 mark] Question 2 continues on the next page Turn over > IML G/Jun24/8465/2H 7 08 Another student used a transect to place quadrats in the field. Figure 2 shows the position of the transect. Figure 2 Living grass A 0 metres Plastic grass 40 metres The student placed a quadrat every 5 metres from point A to point B. Table 2 shows the results. Table 2 Dia ERE a Type of grass Number of plant species 0 Living 4 5 Living 6 10 Living 5 15 Plastic 1 20 Plastic 0 25 Plastic 2 30 Plastic 2 35 Living 4 40 Living 5 G/Jun24/8465/2H Do not write outside the box 10 Do not write outside the box . [6] Small pieces of plastic break off plastic grass and enter rivers and oceans. Leaves from trees take longer to decompose on plastic grass than on living grass. Other plants can grow between pieces of plastic grass. Plastic grass cannot be recycled. Explain how plastic grass affects biodiversity of ecosystems. [6 marks] G/Jun24/8465/2H 10 IMI 11 Do not write outside the box Ecosystems with low biodiversity may have small populations of some species. Why are small populations more likely to become extinct than large populations? [1 mark] Tick (“) one box. A small population may be more varied genetically than a large population. Large populations in the same habitat interact to form communities. Less genetic variation is a greater risk if the ecosystem changes. Suggest two ways biodiversity in and around fields can be increased. Do not refer to plastic grass. [2 marks] Turn over for the next question Turn over > G/Jun24/8465/2H 11 13 Do not write outside the box The electromagnetic spectrum is grouped into different types of wave. Each type of wave has different uses. -[1] Complete the table. [3 marks] Use Type of wave Satellite communications Sterilising surgical instruments Sun tanning Question 3 continues on the next page Turn over > IM G/Jun24/8465/2H 13 14 | Do not write outside the A student investigated the absorption of infrared radiation by a black surface and Pox by a white surface. The student painted the bulb of one thermometer black and the bulb of another thermometer white. Figure 3 shows some of the equipment used. Figure 3 Thermometer Clamp stand ] Infrared heater I Painted Painted black white i 1 [ ] [ “= To power supply This is the method used. 1. Ensure that the initial temperature shown on the thermometers is the same. 2. Switch on the infrared heater. 3. Record the temperature shown on each thermometer every 30 seconds for 5 minutes. G/Jun24/8465/2H 14 16 Do not write outside the Figure 4 shows the results. box Figure 4 55+ Black surface 50 aN 45 40 Temperature t Whit 7 in’C 35-5 mayan H oe : ite surface 30 25 20 1544 T T 10+— : : 7 0 50 100 150 200 250 300 Time in seconds [0] 3].[4] Explain the conclusion that can be made from the results in Figure 4. [2 marks] IMI G/Jun24/8465/2H 16 17 -[5] The paint used for the thermometer bulb painted white was a matt white paint. The investigation was repeated using a thermometer bulb painted with shiny silver paint. The distance between the thermometer and the heater was the same as in the first investigation. The room temperature was the same as in the first investigation. Draw a line on Figure 4 to predict the results for a thermometer painted with shiny silver paint. [2 marks] Turn over for the next question Turn over > G/Jun24/8465/2H Do not write outside the box 17 19 Do not write outside the box Carbon monoxide is an atmospheric pollutant. Carbon monoxide can have dangerous effects on the human body. [0 [4].[1] Describe how carbon monoxide is formed from hydrocarbon fuels. [2 marks] Red blood cells contain haemoglobin. [0] 4].[2] Describe how the shape and internal cell structure of a red blood cell are adaptations to its function. [2 marks] Shape Internal cell structure Question 4 continues on the next page Turn over > IMI 6 9 Gidun24/8465/2H 20 Scientists investigated the effect of breathing in air containing different concentrations of carbon monoxide. The scientists measured the percentage of haemoglobin molecules attached to oxygen at different concentrations of oxygen in the blood. The air breathed contained: e no carbon monoxide e alow concentration of carbon monoxide. Figure 5 shows the results. Figure 5 T T 100 one L 4 EEE Sossus i oe - T f | 80 t t hr * i t ! : ! Percentage (%) i raya | i of haemoglobin 60 f f t t molecules t A t t attached to t oxygen SEaeuae oe aan Coo 40 t ACH Ht t 20 - : roo HH “ I tt EERE EEE EEE 0 0 20 40 60 80 100 Concentration of oxygen in blood in arbitrary units Key IMU Air containing no carbon monoxide Air containing a low concentration of carbon monoxide G/Jun24/8465/2H Do not write outside the ‘box 20