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.
Exam Resource Summary
question(s) marked with an asterisk (*), marks will be awarded for your ability to
The June 2025 Edexcel A Level Biology B 9BIO/03 – Paper 3: General and Practical
your answer logically showing how the points that you make are related or
Principles in Biology – Merged Question Paper & Mark Scheme document combines the
follow
official on from each
examination other
paper where
with appropriate.
its full mark scheme. This paper evaluates students’
understanding of experimental techniques, practical skills, and general biological
Advice
principles, including data analysis, experimental design, and the application of theory to
•
real-world biological contexts. The merged format presents each question alongside its
Read each question carefully
clearbefore you on
start to answer it.
•
marking criteria, providing guidance examiner expectations, mark allocation, and
question
Try to structure.
answer everyThis resource enables targeted revision, development of analytical and
question.
•
evaluative
Check yourskills, and practice
answers in interpreting
if you have time at the and
end.applying biological data, making it
essential for preparation for the June 2025 Edexcel A Level Biology B Paper 3 examination.
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.
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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
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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)
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Answer ..............................................................
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, (b) Draw this yeast cell as it would be seen using a light microscope at
high magnification.
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Labels are not required.
(2)
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(c) The information in the diagram can be used to classify yeast.
(i) State why yeast is classified as eukaryotic not prokaryotic.
(1)
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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)
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, 2 Where two neurones meet they are linked by a synapse.
(a) The diagram shows the structure of a synapse.
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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.
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(3)
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