A-level BIOLOGY Paper 1

A-level BIOLOGY 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. Answer all questions in the spaces provided. box 0 1 . 1 Give the three structural features found in all virus particles and describe the function of one of these features. [2 marks] 1 2 3 Function of one named feature . Explain why viruses are described as acellular and non-living. [2 marks] . Give one reason why antibiotics are not effective against viruses. [1 mark] . Chitin is a polysaccharide. The chitin monomer is a β-glucose molecule with one OH group replaced by an NHCOCH3 group. NHCOCH3 can be represented by N(Ac). Figure 1 shows the monomer that forms chitin and the chitin polymer. Figure 1 Question 2 continues on the next page