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I declare this is my own work.
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A-level
BIOLOGY
Paper 1 o
Time allowed: 2 hours
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Materials
For Examiner’s Use
For this paper you must have:
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a ruler with millimetre measurements
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Question Mark
a scientific calculator.
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1
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Instructions 2
Use black ink or black ball-point pen.
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Fill in the boxes at the top of this page.
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Answer all questions. o o
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You must answer the questions in the spaces provided. Do not write
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outside the box around each page or on blank pages.
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6
If you need extra space for your answer(s), use the lined pages at the end of
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this book. Write the question number against your answer(s).
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8
Show all your working. o o o
Do all rough work in this book. Cross through any work you do not want
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to be marked.
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TOTAL
Information
The marks for the questions are shown in brackets.
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The maximum mark for this paper is 91.
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,IB/M/Jun24/E9 7402/1
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Answer all questions in the spaces provided.
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0 1 . 1
o Give the three structural features found in all virus particles and describe the function
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of one of these features.
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Function of one named feature
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0 1 . 2
o Explain why viruses are described as acellular and non-living.
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[2 marks]
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o Give one reason why antibiotics are not effective against viruses.
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[1 mark]
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0 2 . 1 Chitin is a polysaccharide. The chitin monomer is a β-glucose molecule with one OH
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group replaced by an NHCOCH3 group. NHCOCH3 can be represented by N(Ac).
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Figure 1 shows the monomer that forms chitin and the chitin polymer.
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Figure 1 o
Chitin has a similar structure to cellulose.
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Use Figure 1 to describe three ways the structure of chitin is similar to the structure of
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cellulose.
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Question 2 continues on the next page
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IB/M/Jun24/7402/1