IGCSE BIOLOGY
Please check the examination details below before entering your candidate information
Candidate surname Other names
Centre Number Candidate Number
Pearson Edexcel International GCSE (9–1)
Monday 9 June 2025
Morning (Time: 1 hour 15 minutes) Paper
reference 4BI1/2BR
Biology
UNIT: 4BI1
PAPER: 2BR
You must have: Total Marks
Calculator, ruler
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 70.
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
P78765RA
©2025 Pearson Education Ltd.
Y:1/1/1/1/1/1/1/
*P78765RA0120*
,IGCSE BIOLOGY
Answer ALL questions.
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 Read the passage below. Use the information in the passage and your own knowledge
to answer the questions that follow.
Pollination in fruit trees
Plants need to be pollinated to produce fruits and seeds. Some plants are
self‑pollinated and others are cross‑pollinated.
Self‑pollination is usually the transfer of pollen from flowers on the same tree. In
fruit trees, self‑pollination also includes the transfer of pollen from another tree of
5 the same cultivar. A cultivar is a genetically identical group of trees produced by
selective breeding. Self‑pollinating plants need bees or other insects to transfer
pollen. Examples of self‑pollinated fruit trees are plum, apricot and peach that
have sweet‑tasting, soft fruits.
(Source: © freya‑photographer/Shutterstock) (Source: © Leena Robinson/Shutterstock)
Other fruit trees require cross‑pollination and can only produce fruit by
10 fertilisation from a different cultivar. Cross‑pollination is the transfer of pollen
from one cultivar to the flower of a different cultivar. Self‑incompatibility prevents
the same plant or cultivar from fertilising its own flowers. For example, the pollen
from one cultivar of an apple tree will not fertilise trees of the same cultivar. Most
hard fruit trees such as pear and apple require the presence of two different
15 compatible cultivars for pollination to result in fruit production.
Pollen can be transferred by wind, insects or birds. Many fruit trees are pollinated
by insects. Nut trees are usually pollinated by wind.
After pollination the pollen grain must germinate to lead to fertilisation. The
success of pollination and fertilisation depends on favourable environmental
20 conditions. It also requires the right pollen grain reaching the right flower, as
pollen can only fertilise specific, compatible flowers. For example, pollen from a
peach flower will not pollinate apple flowers.
2
*P78765RA0220*
, IGCSE BIOLOGY
Cross-pollinating fruit trees should be planted no more than 60 m apart. This will
ensure that bees visit the trees often enough to ensure pollination. Nut trees need
25 to be planted no more than 15 m apart.
DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
A further complication is that a few apple and pear cultivars, known as triploids,
produce sterile pollen. Triploid cultivars have three sets of chromosomes within
their cells. A triploid cultivar will require another cultivar for pollination, and the
trees must flower at the same time.
(a) Explain the differences between self-pollination and cross‑pollination.
(lines 3 to 5 and 9 to 11)
(2)
. . . . . . . . . . . .. .. .. .. .. .. .. .. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................................................................................................................................ ................ . . . . . . . . . . . . . . . . . . . .
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(b) Describe the sequence of events from pollen landing on a flower to
fruit production.
(4)
. . . . . . . . . . . .. .. .. .. .. .. .. .. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................................................................................................................................ ................ . . . . . . . . . . . . . . . . . . . .
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. . . . . . . . . . . .. .. .. .. .. .. .. .. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................................................................................................................................ ................ . . . . . . . . . . . . . . . . . . . .
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3
*P78765RA0320* Turn over
Please check the examination details below before entering your candidate information
Candidate surname Other names
Centre Number Candidate Number
Pearson Edexcel International GCSE (9–1)
Monday 9 June 2025
Morning (Time: 1 hour 15 minutes) Paper
reference 4BI1/2BR
Biology
UNIT: 4BI1
PAPER: 2BR
You must have: Total Marks
Calculator, ruler
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 70.
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
P78765RA
©2025 Pearson Education Ltd.
Y:1/1/1/1/1/1/1/
*P78765RA0120*
,IGCSE BIOLOGY
Answer ALL questions.
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 Read the passage below. Use the information in the passage and your own knowledge
to answer the questions that follow.
Pollination in fruit trees
Plants need to be pollinated to produce fruits and seeds. Some plants are
self‑pollinated and others are cross‑pollinated.
Self‑pollination is usually the transfer of pollen from flowers on the same tree. In
fruit trees, self‑pollination also includes the transfer of pollen from another tree of
5 the same cultivar. A cultivar is a genetically identical group of trees produced by
selective breeding. Self‑pollinating plants need bees or other insects to transfer
pollen. Examples of self‑pollinated fruit trees are plum, apricot and peach that
have sweet‑tasting, soft fruits.
(Source: © freya‑photographer/Shutterstock) (Source: © Leena Robinson/Shutterstock)
Other fruit trees require cross‑pollination and can only produce fruit by
10 fertilisation from a different cultivar. Cross‑pollination is the transfer of pollen
from one cultivar to the flower of a different cultivar. Self‑incompatibility prevents
the same plant or cultivar from fertilising its own flowers. For example, the pollen
from one cultivar of an apple tree will not fertilise trees of the same cultivar. Most
hard fruit trees such as pear and apple require the presence of two different
15 compatible cultivars for pollination to result in fruit production.
Pollen can be transferred by wind, insects or birds. Many fruit trees are pollinated
by insects. Nut trees are usually pollinated by wind.
After pollination the pollen grain must germinate to lead to fertilisation. The
success of pollination and fertilisation depends on favourable environmental
20 conditions. It also requires the right pollen grain reaching the right flower, as
pollen can only fertilise specific, compatible flowers. For example, pollen from a
peach flower will not pollinate apple flowers.
2
*P78765RA0220*
, IGCSE BIOLOGY
Cross-pollinating fruit trees should be planted no more than 60 m apart. This will
ensure that bees visit the trees often enough to ensure pollination. Nut trees need
25 to be planted no more than 15 m apart.
DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
A further complication is that a few apple and pear cultivars, known as triploids,
produce sterile pollen. Triploid cultivars have three sets of chromosomes within
their cells. A triploid cultivar will require another cultivar for pollination, and the
trees must flower at the same time.
(a) Explain the differences between self-pollination and cross‑pollination.
(lines 3 to 5 and 9 to 11)
(2)
. . . . . . . . . . . .. .. .. .. .. .. .. .. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................................................................................................................................ ................ . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . .. .. .. .. .. .. .. .. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................................................................................................................................ ................ . . . . . . . . . . . . . . . . . . . .
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(b) Describe the sequence of events from pollen landing on a flower to
fruit production.
(4)
. . . . . . . . . . . .. .. .. .. .. .. .. .. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................................................................................................................................ ................ . . . . . . . . . . . . . . . . . . . .
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3
*P78765RA0320* Turn over
