AQA A- LEVEL BIOLOGY PAPER 1 QP 2023, Exams of Nursing

Download AQA A- LEVEL BIOLOGY PAPER 1 QP 2023 and more Exams Nursing in PDF only on Docsity! *jun237402101* 7402/1IB/M/Jun23/ E10 AQA A- LEVEL BIOLOGY PAPER 1 QP 2023 A-level BIOLOG Y Paper 1 Wednesday 7 June 2023 Afternoon Time allowed: 2 hours Materials For this paper you must have:  a ruler with millimetre measurements  a scientific calculator. Instructions  Use black ink or black ball-point pen.  Fill in the boxes at the top of this page.  Answer all questions.  You must answer the questions in the spaces provided. Do not write outside the box around each page or on blank pages.  If you need extra space for your answer(s), use the lined pages at the end of this book. Write the question number against your answer(s).  Show all your working.  Do all rough work in this book. Cross through any work you do not want to be marked. Information  The marks for the questions are shown in brackets.  The maximum mark for this paper is 91. For Examiner’s Use Questio n Mark 1 2 3 4 5 6 7 8 9 10 TOTAL Please write clearly in block capitals. Centre number Candidate number Surname Forename(s) Candidate signatu re *jun237402101* 7402/1IB/M/Jun23/ E10 4 Do not write outside the *03 * IB/M/ Jun23/7402/1 Turn over ► 5 Do not write outside the *04 * IB/M/ Jun23/7402/1 2 3 . Chitin keeps the tracheae open in the tracheal system of gas exchange in an insect. Gas exchange does not occur in the tracheae. Explain the importance of one adaptation of the gas exchange surface in the tracheal system of an insect. box [2 marks] . Lignin is a polymer found in the walls of xylem vessels in plants. Lignin keeps the xylem vessel open as a continuous tube. Explain the importance of the xylem being kept open as a continuous tube. [3 marks] 20 20 8 6 Do not write outside the *05 * IB/M/ Jun23/7402/1 Turn over for the next question DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED box Turn over ► 9 Do not write outside the IB/M/ Jun23/7402/1 *07* Turn over ► 5 1 0 Do not write outside the IB/M/ Jun23/7402/1 box . In Africa today, most of the human population are resistant to malaria caused by P. vivax. Use your knowledge of natural selection to explain why this resistance is so common in Africa. [4 marks] *0 * 30 9 0 3 . 4 There are an estimated 229 million cases of human malaria worldwide per year. 94% of these cases are found in Africa, but are not caused by P. vivax. P. vivax does cause 61% of the cases of human malaria outside Africa. Use this information to calculate the number of cases worldwide caused by P. vivax each year. [1 mark] Answer cases of malaria 1 1 Do not write outside the *09 * IB/M/ Jun23/7402/1 1. Some hospital patients suffer from diarrhoea caused by infection with the bacterium Clostridium difficile. The C. difficile bacteria release toxins. These toxins cause the diarrhoea. The toxins damage the cells lining the ileum, causing them to lose their microvilli. The damage to the cells reduces the absorption of the products of digestion and reduces the absorption of water, resulting in diarrhoea. Explain why the damage to the cells lining the ileum reduces absorption of the products of digestion and why this reduces absorption of water. box [3 marks] Question 4 continues on the next page 40 14 Do not write outside the *14* IB/M/ Jun23/7402/1 2 3 . The scientists suggest that the anti-toxin antibody could be given to some patients as a form of passive immunity. Use Figure 4 to suggest how this passive immunity would work and which patients should be offered this anti-toxin antibody. box [3 marks] . To be used as passive immunity treatment, the anti-toxin antibody would be injected. If it was given by mouth, it would be digested. Describe how the anti-toxin antibody would be digested. [3 marks] Turn over for the next question Turn over ► 40 40 9 15 Do not write outside the *15* IB/M/ Jun23/7402/1 1 A student investigated the use of cinnamon oil as an antimicrobial substance. She investigated the effect of cinnamon oil on the growth of five different bacterial cultures grown on agar plates. box . The student added 100 mm3 of each bacterial culture from its glass bottle onto a separate agar plate. She spread each bacterial culture evenly over the agar using a spreader. Describe the aseptic techniques she should use. [3 marks] 50 0 5 16 Do not write outside the *16* IB/M/ Jun23/7402/1 Question 5 continues on the next page box Turn over ► 0 5 . 2 On each agar plate, the student cut a well (a hole) in the agar. The well had a diameter of 6 mm. The student added 50 mm3 of cinnamon oil into the well. Calculate the minimum depth of the well to allow the addition of 50 mm3 of cinnamon oil. Use the following equation in your calculation: Volume of a cylinder = πr2 × l Use 3.14 as the value for π. Show your working. [2 marks] Answer mm 19 Do not write outside the *19* IB/M/ Jun23/7402/1 2 box The classification system used in the early 20th century grouped different species of bacteria according to the position and shape of flagella on bacterial cells and by the number of flagella per cell. These were observed using an optical microscope. Each species of bacterium has a characteristic cell shape and arrangement of flagella. These characteristics may be shared with other species within a genus. Flagella are fragile, difficult to stain and may extend from the cell at any angle. . Consider the accuracy and limitations of the early classification of bacteria using the arrangement of flagella. [3 marks] 60 0 6 . 1 Define genome and proteome. [2 marks] Genome Proteome 20 Do not write outside the IB/M/ Jun23/7402/1 3 4 8 . Suggest why several bacterial species have been renamed in recent years. [1 mark] box . Figure 6 shows an image from an optical microscope of a single bacterial cell. Figure 6 This bacterial cell is 2.3 μm long (excluding the flagellum). Calculate the magnification of this image. Show your working. [2 marks] Magnification × Turn over for the next question *17* 60 60 21 Do not write outside the IB/M/ Jun23/7402/1 Turn over ► 24 Do not write outside the *24* IB/M/ Jun23/7402/1 Turn over ► 25 Do not write outside the *25* IB/M/ Jun23/7402/1 1. Scientists investigated a drug called MiTMAB as a treatment for cancer. MiTMAB inhibits cytokinesis. Figure 8 shows drawings of cancer cells seen with an optical microscope from a: sample treated with MiTMAB control sample. Figure 8 A B The cells in drawing A can be identified as those treated with MiTMAB. box Explain why. [2 marks] 80 26 Do not write outside the *26* IB/M/ Jun23/7402/1 2. MiTMAB acts as a non-competitive inhibitor of an enzyme called dynamin. Suggest how MiTMAB can cause dynamin to become inactive. [3 marks] box Question 8 continues on the next page Turn over ► 80 29 Do not write outside the *29* IB/M/ Jun23/7402/1 Dengue fever is a human disease caused by the dengue virus. Scientists designed an ELISA test to detect antibodies to the dengue virus in a patient’s blood sample. Figure 10 shows a diagram of this test and some information about how it works. Figure 10 Figure 11 shows the negative and positive results that were produced 20 minutes after the use of the test shown in Figure 10. Figure 11 box0 9 30 Do not write outside the *30* IB/M/ Jun23/7402/1 1 2 . Suggest what is on the test at line T and explain what causes the line to appear in a positive test. box [2 marks] . A line at C shows that the test has worked. Suggest one reason why a line at C shows the test has worked. [1 mark] Question 9 continues on the next page Turn over ► 90 90 31 Do not write outside the *31* IB/M/ Jun23/7402/1 3 4 Figure 12 shows a flowchart of how the anti-human antibodies with enzyme attached are produced. Figure 12 . Suggest why the fused cells allow continuous production of monoclonal antibodies. [2 marks] box . Evaluate the ethics of the production process shown in Figure 12. [1 mark] 90 90 34 Do not write outside the IB/M/ Jun23/7402/1 rtant becaus e people sufferin g with dengue fever can becom e ill very quickly and may need hospita l treatm ent. Scientists compared the effectiven ess of three diagnosti c tests for dengue fever.  Laborat ory- based test – a patient’ s blood sample is sent from the doctor’ s clinic to a laborat ory for testing.  Current test used in the doctor’s clinic.  New test to be used in the doctor’s clinic – the ELISA test shown in Figures 10 and 11 (on page 24). The scientists’ results are shown in Table 3. A blood sample from each patient with confirmed dengue fever at each time after onset of symptoms was tested with all three diagnostic tests. Table 3 Time after onset of symptoms / days Number of confirmed dengue fever patients tested Number of positive results Laborator y- based test Current test New test 1–2 14 10 0 6 3–4 38 28 6 24 5–7 18 8 14 14 box 35 Do not write outside the *35* IB/M/ Jun23/7402/1 5 6 . The scientists recommend that the new test is used for the identification of dengue fever in all countries around the world. box Discuss this recommendation. Use all the information given. [3 marks] . The dengue virus causes damage to capillaries so that blood proteins move out of the capillaries into the tissue fluid. Explain how this would affect the return of tissue fluid into the capillaries. [2 marks] Turn over for the next question Turn over ► 90 90 11 36 Do not write outside the *36* IB/M/ Jun23/7402/1 1. Describe how a quaternary protein is formed from its monomers. Do not include the process of translation in your answer. [5 marks] box01 39 Do not write outside the *39* IB/M/ Jun23/7402/1 There are no questions printed on this page DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED box 40 *40* IB/M/ Jun23/7402/1 outside the Do not write box Questio n number Additional page, if required. Write the question numbers in the left-hand margin. 41 *41* IB/M/ Jun23/7402/1 Do not write outside the box Questio n number Additional page, if required. Write the question numbers in the left-hand margin.