Please check the examination details below before entering your candidate information
Candidate surname Other names
Centre Number Candidate Number
Pearson Edexcel International Advanced Level
Tuesday 6 May 2025
Morning (Time: 1 hour 30 minutes) Paper
reference WBI11/01
Biology
International Advanced Subsidiary / Advanced Level
UNIT 1: Molecules, Diet, Transport and Health
You must have: Total Marks
Scientific calculator, ruler, HB pencil
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.
•• Calculators may be used.
You must show all your working out with your answer clearly identified at the
end of your solution.
Information:
•• The total mark for this paper is 80.
The marks for each question are shown in brackets
– use this as a guide as to how much time to spend on each question.
• Instructure
questions marked with an asterisk (*), marks will be awarded for your ability to
your answer logically, showing how the points you make are related or
follow on from each other where appropriate.
Advice:
•• Read each question carefully before you start to answer it.
Try to answer every question.
• Check your answers if you have time at the end. Turn over
P78735A
©2025 Pearson Education Ltd.
Y:1/1/1/1/1/
*P78735A0128*
,DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
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BLANK PAGE
2
, Answer ALL questions. Write your answers in the spaces provided.
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: One risk factor for cardiovascular disease is a short blood clotting time.
One test for measuring blood clotting time is the prothrombin time (PT).
(a) Read through the following passage about prothrombin and the blood
clotting process.
Complete the passage by writing the most appropriate word or words on the
dotted lines.
(3)
Prothrombin is transported in the . . . . ......................................................................................... of a human.
It is converted into thrombin by an enzyme called .................................................................................... .
The substrate for thrombin is . . . . . . . . . . . . . . . . ............................................................................. .
(b) Which pair of drugs is used to treat patients who have short blood clotting times?
(1)
A anticoagulants and antihypertensives
B anticoagulants and platelet inhibitors
C antihypertensives and statins
D platelet inhibitors and statins
(c) The range for a healthy PT is between 10 and 13 seconds.
A person with a PT of 8.5 seconds was treated with a drug to increase the PT time
to 10 seconds.
Calculate the percentage increase in PT from 8.5 seconds to 10 seconds.
(1)
Answer ............................................... . . . . . . . . . . . . . . . %
(Total for Question 1 = 5 marks)
3
*P78735A0328* Turn over
Candidate surname Other names
Centre Number Candidate Number
Pearson Edexcel International Advanced Level
Tuesday 6 May 2025
Morning (Time: 1 hour 30 minutes) Paper
reference WBI11/01
Biology
International Advanced Subsidiary / Advanced Level
UNIT 1: Molecules, Diet, Transport and Health
You must have: Total Marks
Scientific calculator, ruler, HB pencil
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.
•• Calculators may be used.
You must show all your working out with your answer clearly identified at the
end of your solution.
Information:
•• The total mark for this paper is 80.
The marks for each question are shown in brackets
– use this as a guide as to how much time to spend on each question.
• Instructure
questions marked with an asterisk (*), marks will be awarded for your ability to
your answer logically, showing how the points you make are related or
follow on from each other where appropriate.
Advice:
•• Read each question carefully before you start to answer it.
Try to answer every question.
• Check your answers if you have time at the end. Turn over
P78735A
©2025 Pearson Education Ltd.
Y:1/1/1/1/1/
*P78735A0128*
,DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA DO NOT WRITE IN THIS AREA
*P78735A0228*
BLANK PAGE
2
, Answer ALL questions. Write your answers in the spaces provided.
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: One risk factor for cardiovascular disease is a short blood clotting time.
One test for measuring blood clotting time is the prothrombin time (PT).
(a) Read through the following passage about prothrombin and the blood
clotting process.
Complete the passage by writing the most appropriate word or words on the
dotted lines.
(3)
Prothrombin is transported in the . . . . ......................................................................................... of a human.
It is converted into thrombin by an enzyme called .................................................................................... .
The substrate for thrombin is . . . . . . . . . . . . . . . . ............................................................................. .
(b) Which pair of drugs is used to treat patients who have short blood clotting times?
(1)
A anticoagulants and antihypertensives
B anticoagulants and platelet inhibitors
C antihypertensives and statins
D platelet inhibitors and statins
(c) The range for a healthy PT is between 10 and 13 seconds.
A person with a PT of 8.5 seconds was treated with a drug to increase the PT time
to 10 seconds.
Calculate the percentage increase in PT from 8.5 seconds to 10 seconds.
(1)
Answer ............................................... . . . . . . . . . . . . . . . %
(Total for Question 1 = 5 marks)
3
*P78735A0328* Turn over
