OCR A biology 2020 depth (as level) paper & markscheme
Tuesday 19 May 2020 Afternoon Time allowed: 1 hour 30 minutes
Materials
For this paper you must have:
• a ruler with millimetre measurements
• a scientific ca
...
OCR A biology 2020 depth (as level) paper & markscheme
Tuesday 19 May 2020 Afternoon Time allowed: 1 hour 30 minutes
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 75.
*JUN207401101* IB/M/Jun20/E12 7401/1
Answer all questions in the spaces provided.
box
Figure 1 shows the structure of molecules found in organisms.
Figure 1
. Complete Table 1 by putting the correct letter, A, B, C or D, in the box next to each statement. Each letter may be used once, more than once, or not at all.
[4 marks]
Table 1
Letter
Statement
is a monomer in an enzyme’s active site
is a monomer in cellulose
is produced during photosynthesis and respiration
forms a polymer that gives a positive result with a biuret test
. Raffinose is a trisaccharide of three monosaccharides: galactose, glucose and fructose. The chemical formulae of these monosaccharides are:
• galactose = C6H12O6
• glucose = C6H12O6
• fructose = C6H12O6
Give the number of carbon atoms, hydrogen atoms and oxygen atoms in a molecule of raffinose.
box
[1 mark]
Number of carbon atoms
Number of hydrogen atoms
Number of oxygen atoms
. A biochemical test for reducing sugar produces a negative result with raffinose solution.
Describe a biochemical test to show that raffinose solution contains a non-reducing sugar.
[3 marks]
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