Candidate surname Other names
Centre Number Candidate Number
Pearson Edexcel International GCSE (9–1)
Tuesday 13 May 2025
Afternoon (Time: 2 hours) Paper
reference 4BI1/1BR 4SD0/1BR
Biology
UNIT: 4BI1
Science (Double Award) 4SD0
PAPER: 1BR
You must have: Total Marks
Ruler, calculator
Instructions
•• Use black ink or ball-point pen.
If pencil is used for diagrams/sketches/graphs it must be dark (HB or B).
• 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.
• Show all the steps in any calculations and state the units.
Information
•• The total mark for this paper is 110.
The marks for each question are shown in brackets
– use this as a guide as to how much time to spend on each question.
Advice
•• Read each question carefully before you start to answer it.
Write your answers neatly and in good English.
•• Try to answer every question.
Check your answers if you have time at the end.
Turn over
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, Answer ALL questions.
Some questions must be answered with a cross in a box . If you change your mind about an
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answer, put a line through the box and then mark your new answer with a cross .
1 The photograph shows a fungus called Mucor growing on an agar plate.
Cells within Mucor contain nuclei and mitochondria.
(Source: © Dr_Microbe/Alamy Stock Photo)
(a) (i) Which of these is a correct statement about the fungus, Mucor?
(1)
A Mucor is a eukaryotic organism with cell walls made of chitin
B Mucor is a eukaryotic organism with cell walls made of cellulose
C Mucor is a prokaryotic organism with cell walls made of chitin
D Mucor is a prokaryotic organism with cell walls made of cellulose
(ii) Plant cells contain chloroplasts, cytoplasm and starch.
How many of these are also present in a fungus such as Mucor?
(1)
A 0
B 1
C 2
D 3
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, (iii) The fungus in the diagram is circular with a radius of 45 mm.
Calculate the area, in mm2 , of this circle.
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Give your answer to 2 significant figures.
[area = πr2 π = 3.14]
(2)
area of circle = ....................................... ................ . . . . . . . mm2
(b) Mucor can reproduce using asexual or sexual reproduction.
(i) State two differences between asexual and sexual reproduction.
(2)
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(ii) Explain why it is an advantage for Mucor to be able to reproduce using
sexual reproduction.
(2)
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(Total for Question 1 = 8 marks)
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, 2 The diagram shows parts of the human respiratory system with some structures
labelled.
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lung
X
(a) (i) Which of these is the structure labelled X?
(1)
A alveolus
B bronchiole
C bronchus
D trachea
(ii) State why a lung is described as an organ.
(1)
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(iii) Explain how contraction of the diaphragm causes air to move into the lungs.
(3)
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