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 in Section A. • Answer one question from Section B. • 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 78. Please write clearly in block capitals. Centre number Candidate number Surname Forename(s) Candidate signature I declare this is my own work. A-level BIOLOGY Paper 3 2 *02* IB/M/Jun24/7402/3 Do not write outside the Section A box Answer all questions in this section. You are advised to spend no more than 1 hour and 15 minutes on this section. 0 1 . 1 In the following passage, each numbered space can be filled with a biological term. Each type of cell has specific molecules on its (1) that identify it. An antibody is a (2) with two (3) binding sites. Antibodies are made and released by (4) cells. Vaccines can provide protection for individuals and populations against disease. The response to a vaccine is an example of (5) immunity. (6) immunity occurs when a large proportion of a population becomes immune to a disease. Write the correct biological term beside each number below that matches the space in the passage. [3 marks] 1 2 3 4 5 6 0 1 . 2 There is currently no effective vaccine available for HIV. Suggest one reason why. [1 mark] 3 *03* Turn over ► IB/M/Jun24/7402/3 Do not write outside the box 0 1 . 3 Table 1 shows the action of two antibiotics. Table 1 Antibiotic Action of antibiotic Ciprofloxacin Causes double-stranded DNA to break apart Penicillin Prevents formation of crosslinks between murein chains Using the information in Table 1, explain why each antibiotic is not effective against HIV. [2 marks] Ciprofloxacin Penicillin Turn over for the next questio