PDF
Please check the examination details below before entering your candidate information
Candidate surname Other names
Centre Number Candidate Number
Pearson Edexcel Level 3 GCE
Thursday 4 June 2026
Afternoon (Time: 2 hours) Paper
reference 9BN0/01
Biology A (Salters Nuffield)
Advanced
PAPER 1: The Natural Environment and
Species Survival
You must have: Total Marks
Calculator, HB pencil, ruler
Instructions
•• Use black ink or ball-point pen.
Fill in the boxes at the top of this page with your name,
centre number and candidate number.
•• Answer all questions.
Show all your working out in calculations and include units where appropriate.
• Answer the questions in the spaces provided
– there may be more space than you need.
Information
•• The total mark for this paper is 100.
The marks for each question are shown in brackets
– use this as a guide as to how much time to spend on each question.
•• You may use a scientific calculator.
In questions marked with an asterisk (*), marks will be awarded for your ability to
structure your answer logically showing how the points that you make are related
or follow on from each other where appropriate.
Advice
•• Read each question carefully before you start to answer it.
Try to answer every question.
• Check your answers if you have time at the end.
Turn over
P79058A
©2026 Pearson Education Ltd.
P:1/1/1/1/1/1/1/1/1/1/1/
*P79058A0136*
, Answer ALL questions. 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
DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
answer, put a line through the box and then mark your new answer with a cross .
1 Cystic fibrosis (CF) is a disorder caused by a mutation in the gene for the
CFTR protein.
(a) The number of nucleotide base pairs present in the non-mutated form of the
gene is 189 000.
(i) Which of the following could result in a gene mutation?
1. insertion of an extra base
2. removal of one base
3. removal of three bases
(1)
A 1 and 2 only
B 2 and 3 only
C 1, 2 and 3
D none of them
(ii) Which is the maximum number of amino acids that can be present in the
CFTR protein coded for by the non-mutated gene?
(1)
A 62 999
B 63 000
C 186 000
D 566 991
2
*P79058A0236*
, (iii) Explain how the genetic code determines the maximum number of amino
acids in this protein.
(2)
DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
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(b) People with cystic fibrosis produce thick mucus.
Explain how this thick mucus makes the digestion of food difficult.
(3)
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(Total for Question 1 = 7 marks)
3
*P79058A0336* Turn over
,DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
*P79058A0436*
BLANK PAGE
4
Please check the examination details below before entering your candidate information
Candidate surname Other names
Centre Number Candidate Number
Pearson Edexcel Level 3 GCE
Thursday 4 June 2026
Afternoon (Time: 2 hours) Paper
reference 9BN0/01
Biology A (Salters Nuffield)
Advanced
PAPER 1: The Natural Environment and
Species Survival
You must have: Total Marks
Calculator, HB pencil, ruler
Instructions
•• Use black ink or ball-point pen.
Fill in the boxes at the top of this page with your name,
centre number and candidate number.
•• Answer all questions.
Show all your working out in calculations and include units where appropriate.
• Answer the questions in the spaces provided
– there may be more space than you need.
Information
•• The total mark for this paper is 100.
The marks for each question are shown in brackets
– use this as a guide as to how much time to spend on each question.
•• You may use a scientific calculator.
In questions marked with an asterisk (*), marks will be awarded for your ability to
structure your answer logically showing how the points that you make are related
or follow on from each other where appropriate.
Advice
•• Read each question carefully before you start to answer it.
Try to answer every question.
• Check your answers if you have time at the end.
Turn over
P79058A
©2026 Pearson Education Ltd.
P:1/1/1/1/1/1/1/1/1/1/1/
*P79058A0136*
, Answer ALL questions. 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
DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
answer, put a line through the box and then mark your new answer with a cross .
1 Cystic fibrosis (CF) is a disorder caused by a mutation in the gene for the
CFTR protein.
(a) The number of nucleotide base pairs present in the non-mutated form of the
gene is 189 000.
(i) Which of the following could result in a gene mutation?
1. insertion of an extra base
2. removal of one base
3. removal of three bases
(1)
A 1 and 2 only
B 2 and 3 only
C 1, 2 and 3
D none of them
(ii) Which is the maximum number of amino acids that can be present in the
CFTR protein coded for by the non-mutated gene?
(1)
A 62 999
B 63 000
C 186 000
D 566 991
2
*P79058A0236*
, (iii) Explain how the genetic code determines the maximum number of amino
acids in this protein.
(2)
DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
. . . . . . . . . . . .. .. .. .. .. .. .. .. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................................................................................................................................ ................ . . . . . . . . . . . . . . . . . . . .
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(b) People with cystic fibrosis produce thick mucus.
Explain how this thick mucus makes the digestion of food difficult.
(3)
. . . . . . . . . . . .. .. .. .. .. .. .. .. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................................................................................................................................ ................ . . . . . . . . . . . . . . . . . . . .
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(Total for Question 1 = 7 marks)
3
*P79058A0336* Turn over
,DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
*P79058A0436*
BLANK PAGE
4
