surname names
Number Number
June 2025 Edexcel: A Level Biology B
9BIO/03 Paper 3 – General and
Practical Principles in Biology – Merged
Question Paper & Mark Scheme
Morning (Time: 2 hours 30 minutes) Paper
B 🟐 🟐
Advanced
PAPER 3: General and Practical Principles in Biology
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.
Answer the questions in the spaces provided
– there may be more space than you need.
Information
•• The total mark for this paper is 120.
The marks for each question are shown in brackets
• Instructure
– use this as a guide as to how much time to spend on each question.
question(s) marked with an asterisk (*), marks will be awarded for your ability to
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.
• Check answer
Try to every question.
• your answers if you have time at the end.
Turn over
P74462A
©2025 Pearson Education Ltd.
Y:1/1/1/1/1/1/1/1/1/
, Answer ALL questions.
Write your answers in the spaces provided.
DO NOT WRITE IN THIS AREA
1 Saccharomyces cerevisiae (yeast) is a single-celled organism widely used in brewing
and baking.
The diagram shows a drawing of a yeast cell, as seen using an electron microscope.
A cytoplasm containing
cell surface glycogen granules
membrane
nucleus containing 16
linear chromosomes
cell wall made of
chitin and mannose
DO NOT WRITE IN THIS AREA
vacuole
mitochondrion
B
(a) The actual size of the cell measured from point A to point B is 6 µm.
Calculate the magnification of this yeast cell.
Give your answer to the nearest whole number.
(2)
DO NOT WRITE IN THIS AREA
Answer ..............................................................
2
■■■■
, (b) Draw this yeast cell as it would be seen using a light microscope at
high magnification.
DO NOT WRITE IN THIS AREA
Labels are not required.
(2)
DO NOT WRITE IN THIS AREA
(c) The information in the diagram can be used to classify yeast.
(i) State why yeast is classified as eukaryotic not prokaryotic.
(1)
. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . ......................
DO NOT WRITE IN THIS AREA
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(ii) State why yeast is not classified as a plant.
(1)
. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . . . .. . .. . .. . . ......................
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(Total for Question 1 = 6 marks)
3
■■■■ Turn over
, 2 Where two neurones meet they are linked by a synapse.
(a) The diagram shows the structure of a synapse.
DO NOT WRITE IN THIS AREA
vesicle
axon
mitochondrion
(i) Draw an arrow on the diagram to show the direction in which the
nerve impulse travels.
(1)
(ii) Describe the role of acetylcholine in synaptic transmission.
DO NOT WRITE IN THIS AREA
(3)
. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. .. . . .. . .. . .. . .. . . . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . ......................
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4
■■■■
Number Number
June 2025 Edexcel: A Level Biology B
9BIO/03 Paper 3 – General and
Practical Principles in Biology – Merged
Question Paper & Mark Scheme
Morning (Time: 2 hours 30 minutes) Paper
B 🟐 🟐
Advanced
PAPER 3: General and Practical Principles in Biology
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.
Answer the questions in the spaces provided
– there may be more space than you need.
Information
•• The total mark for this paper is 120.
The marks for each question are shown in brackets
• Instructure
– use this as a guide as to how much time to spend on each question.
question(s) marked with an asterisk (*), marks will be awarded for your ability to
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.
• Check answer
Try to every question.
• your answers if you have time at the end.
Turn over
P74462A
©2025 Pearson Education Ltd.
Y:1/1/1/1/1/1/1/1/1/
, Answer ALL questions.
Write your answers in the spaces provided.
DO NOT WRITE IN THIS AREA
1 Saccharomyces cerevisiae (yeast) is a single-celled organism widely used in brewing
and baking.
The diagram shows a drawing of a yeast cell, as seen using an electron microscope.
A cytoplasm containing
cell surface glycogen granules
membrane
nucleus containing 16
linear chromosomes
cell wall made of
chitin and mannose
DO NOT WRITE IN THIS AREA
vacuole
mitochondrion
B
(a) The actual size of the cell measured from point A to point B is 6 µm.
Calculate the magnification of this yeast cell.
Give your answer to the nearest whole number.
(2)
DO NOT WRITE IN THIS AREA
Answer ..............................................................
2
■■■■
, (b) Draw this yeast cell as it would be seen using a light microscope at
high magnification.
DO NOT WRITE IN THIS AREA
Labels are not required.
(2)
DO NOT WRITE IN THIS AREA
(c) The information in the diagram can be used to classify yeast.
(i) State why yeast is classified as eukaryotic not prokaryotic.
(1)
. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . ......................
DO NOT WRITE IN THIS AREA
. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . . . . .. . .. . .. . .. . .. . .. . .. . .. . . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . ......................
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(ii) State why yeast is not classified as a plant.
(1)
. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . . . .. . .. . .. . . ......................
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(Total for Question 1 = 6 marks)
3
■■■■ Turn over
, 2 Where two neurones meet they are linked by a synapse.
(a) The diagram shows the structure of a synapse.
DO NOT WRITE IN THIS AREA
vesicle
axon
mitochondrion
(i) Draw an arrow on the diagram to show the direction in which the
nerve impulse travels.
(1)
(ii) Describe the role of acetylcholine in synaptic transmission.
DO NOT WRITE IN THIS AREA
(3)
. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . .. . .. .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. .. . . .. . .. . .. . .. . . . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . ......................
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4
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