Tuesday 5 May 2026
Afternoon (Time: 1 hour 30 minutes)
Paper
reference WBI11/01A
Biology
International Advanced Subsidiary/Advanced Level
UNIT 1: Molecules, Diet, Transport and Health
Question Paper Mark Scheme (Results)
You must have: Answer Book (sent separately)
Scientific calculator, ruler, HB pencil
Do not return this question paper with the answer book.
Summer 2026
Pearson Edexcel International Advanced Subsidiary
Level in Biology
WBI11/ 01A
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, Answer ALL questions. Edexcel and BTEC Qualifications
Write your answers in the spaces provided.
Some questions must be answered with a cross in a box . If you change your mind about an
answer, put a line through the box and then mark your new answer with a cross . Edexcel and BTEC qualifications are awarded by Pearson, the UK’s
largest awarding body. We provide a wide range of qualifications
1 The diagram shows some structures in part of a cell membrane.
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Pearson: helping people progress, everywhere
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1 (a) (i) Which one of these pairs of structures is made of protein? involved in education for over 150 years, and by working across 70 countries, in
(1) 100 languages, we have built an international reputation for our commitment to
high standards and raising achievement through innovation in education. Find out
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C Q and W
D V and W
1 (a) (ii) Which one of these pairs of structures is nonpolar (hydrophobic)?
(1)
A P and Q
B Q and U
C R and T
Summer 2026
D U and W Question Paper Log Number P81797A
Publication Code WBI11_01A_2606_MS
All the material in this publication is
Pearson
2 P81797A
,1 (a) (iii) Which structure requires ATP to function? General Marking Guidance
(1)
• All candidates must receive the same treatment. Examiners must mark the first
A R candidate in exactly the same way as they mark the last.
B T • Mark schemes should be applied positively. Candidates must be rewarded for
what they have shown they can do rather than penalised for omissions.
C U
• Examiners should mark according to the mark scheme not according to their
D V
perception of where the grade boundaries may lie.
1 (b) Explain how the properties of the cell membrane enable a cell to release • There is no ceiling on achievement. All marks on the mark scheme should be
extracellular enzymes by exocytosis.
(2) used appropriately.
• All the marks on the mark scheme are designed to be awarded. Examiners
(Total for Question 1 = 5 marks)
should always award full marks if deserved, i.e. if the answer matches the mark
scheme. Examiners should also be prepared to award zero marks if the
candidate’s response is not worthy of credit according to the mark scheme.
• Where some judgement is required, mark schemes will provide the principles by
which marks will be awarded and exemplification may be limited.
• When examiners are in doubt regarding the application of the mark scheme to a
candidate’s response, the team leader must be consulted.
• Crossed out work should be marked UNLESS the candidate has replaced it with
an alternative response.
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, 2 The process of protein synthesis occurs in two stages and involves: Question The diagram shows some structures in part of a cell membrane. Mark
number
• messenger RNA (mRNA)
• transfer RNA (tRNA)
• enzymes.
2 (a) Name the first stage that produces mRNA using DNA as a template and the
second stage that involves tRNA.
(1) Which one of these pairs of structures is made of protein?
2 (b) The diagram shows the sequence of bases on part of a DNA strand.
Answer
2 (b) (i) Complete the diagram to show the sequence of bases on the mRNA strand 1(a)(i)
synthesised in the first stage of protein synthesis.
The only correct answer is D
(1)
DNA strand G A G C A A T T G A is incorrect as P is a phosphate
B is incorrect as P is a phosphate and Q is a fatty acid
C is incorrect as Q is a fatty acid
(1)
mRNA
2 (b) (ii) Describe the role of enzymes in the synthesis of mRNA using a DNA
molecule.
(2)
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