AS
BIOLOGY
7401/2
Paper 2
Version: 1.0 Final
*JUN237401201*
IB/M/Jun23/E9 7401/2
For Examiner’s Use
Question
... [Show More] Mark
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10
TOTAL
Thursday 25 May 2023 Morning 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.
Please write clearly in block capitals.
Centre number Candidate number
Surname
Forename(s)
Candidate signature
I declare this is my own work.
AS
BIOLOGY
Paper 2
2
*02*
IB/M/Jun23/7401/2
Do not write
outside the
Answer all questions in the spaces provided. box
0 1 . 1 Which statement about the function of ribosomes is correct?
Tick () one box.
[1 mark]
Site of transcription, catalyse the joining of amino acids by hydrolysis
reactions
Site of transcription, catalyse the joining of nucleotides by
condensation reactions
Site of translation, catalyse the joining of amino acids by
condensation reactions
Site of translation, catalyse the joining of nucleotides by hydrolysis
reactions
0 1 . 2 Name two biological molecules that can be coded for by a gene.
Do not include a polypeptide or protein in your answer.
[1 mark]
1
2
3
*03*
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IB/M/Jun23/7401/2
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outside the
box 0 1 . 3 Scientists investigated the structure of the endoplasmic reticulum.
Table 1 shows some of the scientists’ results.
Table 1
Type of endoplasmic reticulum Percentage of endoplasmic
reticulum made of phospholipids
Rough 46.8
Smooth 52.5
Use the data in Table 1 to suggest how the structure of rough endoplasmic reticulum
is different from the structure of smooth endoplasmic reticulum and how this is
related to their functions.
[3 marks]
Turn over for the next question
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4
*04*
IB/M/Jun23/7401/2
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box 0 2 . 1 Figure 1 shows an ATP synthase enzyme in the inner mitochondrial membrane.
Figure 1
Complete the passage with the appropriate terms.
[2 marks]
ATP synthase comprises several polypeptides, so is said to have
a structure.
It catalyses the synthesis of an ATP molecule by a
reaction; this involves the of a water molecule.
The ATP synthase in Figure 1 is in a mitochondrion so would catalyse reactions
during .
5
*05*
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IB/M/Jun23/7401/2
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box
6
0 2 . 2 As shown in Figure 1, ATP synthase has two functions.
• It catalyses the synthesis of ATP.
• It allows the movement of H+ ions.
Suggest how the shape of the ATP synthase allows it to have these two functions.
Explain your answers.
[4 marks]
Catalyses the synthesis of ATP
Allows the movement of H+ ions
Turn over for the next question
6
*06*
IB/M/Jun23/7401/2
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outside the
0 3 Galacto box -oligosaccharides (GOS) are polymers of galactose.
0 3 . 1 Explain why GOS are described as polysaccharides [Show Less]