Disclaimer: This document was created by department heads with many years of experience teaching the
Pearson Edexcel IGCSE Biology course. We cannot however guarantee that it is an accurate representation
of the Summer 2025 examinations and students should not treat it as such. Please use this as an aid, alongside
other methods of revision.
Pearson Edexcel International GCSE (9-1)
Monday 9 June 2025
Morning (Time: 1 hour 15 minutes)
Biology
Unit: 4BI1
Paper: 2B
You must have:
Calculator, ruler
Instructions
• Use black ink or a ballpoint pen.
• 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 →
© 2025 Empirical Tuition. All rights reserved.
, Answer all questions.
1. Read the passage below. Use the information in the passage and your own knowledge to answer
the questions that follow.
Pig Hearts for Human Transplants
Scientists are exploring the use of pig hearts as ‘scaffolds’ for growing human-
compatible organs. Pig hearts provide a structure that can be coated with human
stem cells, which develop into heart tissue. This innovative approach is being
developed to address the global shortage of donor hearts, with over 7,000 people
5 in the UK alone waiting for a heart transplant each year.
Previous attempts to use unmodified pig hearts for transplants have failed because
10 phagocytes in the human immune system attacked the pig tissue. To overcome this,
scientists use pig hearts as a scaffold and coat them with human cells grown from
2
, stem cells. These stem cells are often taken from the patient to reduce the risk of
immune rejection. They must be grown in carefully controlled conditions to ensure
they develop into functional tissues. Once coated, the heart closely resembles
human tissue, reducing the likelihood of rejection. The coating process can take up
to two weeks and costs around £50,000 per heart. This costs approximately the
same as a traditional transplant using a human heart.
15 A key advantage of this method is the hope that patients may not require
immunosuppressive drugs after the transplant. These drugs, which are currently
used to prevent rejection in organ transplants, cost around £1,500 per month for
life. For some patients with coronary heart disease (CHD), managing their
condition with statins, which cost approximately £750 per year, may remain a
20 more practical and cost-effective option.
CHD is a major cause of heart transplants, accounting for around 65,000 deaths in
the UK every year. While pig hearts coated with stem cells offer a potential solution
for severe cases, ethical concerns about the use of animals and the high cost of
treatment remain. However, this innovative approach represents a significant step
25 forward in the search for sustainable solutions to the organ shortage crisis.
(a) State what is meant by the term stem cell (line 3). (1)
(b) Describe the process by which phagocytes destroy pathogens in the body (line 7). (4)
3
Pearson Edexcel IGCSE Biology course. We cannot however guarantee that it is an accurate representation
of the Summer 2025 examinations and students should not treat it as such. Please use this as an aid, alongside
other methods of revision.
Pearson Edexcel International GCSE (9-1)
Monday 9 June 2025
Morning (Time: 1 hour 15 minutes)
Biology
Unit: 4BI1
Paper: 2B
You must have:
Calculator, ruler
Instructions
• Use black ink or a ballpoint pen.
• 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 →
© 2025 Empirical Tuition. All rights reserved.
, Answer all questions.
1. Read the passage below. Use the information in the passage and your own knowledge to answer
the questions that follow.
Pig Hearts for Human Transplants
Scientists are exploring the use of pig hearts as ‘scaffolds’ for growing human-
compatible organs. Pig hearts provide a structure that can be coated with human
stem cells, which develop into heart tissue. This innovative approach is being
developed to address the global shortage of donor hearts, with over 7,000 people
5 in the UK alone waiting for a heart transplant each year.
Previous attempts to use unmodified pig hearts for transplants have failed because
10 phagocytes in the human immune system attacked the pig tissue. To overcome this,
scientists use pig hearts as a scaffold and coat them with human cells grown from
2
, stem cells. These stem cells are often taken from the patient to reduce the risk of
immune rejection. They must be grown in carefully controlled conditions to ensure
they develop into functional tissues. Once coated, the heart closely resembles
human tissue, reducing the likelihood of rejection. The coating process can take up
to two weeks and costs around £50,000 per heart. This costs approximately the
same as a traditional transplant using a human heart.
15 A key advantage of this method is the hope that patients may not require
immunosuppressive drugs after the transplant. These drugs, which are currently
used to prevent rejection in organ transplants, cost around £1,500 per month for
life. For some patients with coronary heart disease (CHD), managing their
condition with statins, which cost approximately £750 per year, may remain a
20 more practical and cost-effective option.
CHD is a major cause of heart transplants, accounting for around 65,000 deaths in
the UK every year. While pig hearts coated with stem cells offer a potential solution
for severe cases, ethical concerns about the use of animals and the high cost of
treatment remain. However, this innovative approach represents a significant step
25 forward in the search for sustainable solutions to the organ shortage crisis.
(a) State what is meant by the term stem cell (line 3). (1)
(b) Describe the process by which phagocytes destroy pathogens in the body (line 7). (4)
3
