worked solutions
model answers
, Oxford Cambridge and RSA
Thursday 5 June 2025 – Afternoon
A Level Biology B (Advancing Biology)
H422/01 Fundamentals of biology
Time allowed: 2 hours 15 minutes
You must have:
* 1 8 4 8 9 0 7 1 4 4 *
• a ruler (cm/mm)
You can use:
• a scientific or graphical calculator
* H 4 2 2 0 1 *
Please write clearly in black ink. Do not write in the barcodes.
Centre number Candidate number
First name(s)
Last name
INSTRUCTIONS
• Use black ink. You can use an HB pencil, but only for graphs and diagrams.
• Write your answer to each question in the space provided. If you need extra space use
the lined pages at the end of this booklet. The question numbers must be clearly shown.
• Answer all the questions.
• Where appropriate, your answer should be supported with working. Marks might be
given for using a correct method, even if your answer is wrong.
INFORMATION
• The total mark for this paper is 110.
• The marks for each question are shown in brackets [ ].
• Quality of extended response will be assessed in questions marked with an asterisk (*).
• This document has 44 pages.
ADVICE
• Read each question carefully before you start your answer.
© OCR 2025 [601/4720/9] OCR is an exempt Charity
DC (DE/SG) 347647/4 Turn over
for more: tyrionpapers.com
, 2
Section A
You should spend a maximum of 40 minutes on this section.
Write your answer for each question in the box provided.
1 Which type of blood cell is shown in the annotated drawing?
Non-granulated cytoplasm
Kidney-bean shaped nucleus
A Erythrocyte
B Lymphocyte
C Monocyte
D Neutrophil
Your answer [1]
2 Which technique uses fluorescent markers to tag cells so they can be counted and identified
when passed through a laser beam?
A Differential staining
B Flow cytometry
C Gel electrophoresis
D Haemocytometry
Your answer [1]
© OCR 2025
for more: tyrionpapers.com
, 3
3 Which statement about ATP is not correct?
A It can be hydrolysed to form AMP.
B It contains the pentose sugar, ribose.
C It contains the pyrimidine nitrogenous base, adenine.
D It is a phosphorylated nucleotide.
Your answer [1]
4 The percentage base composition of DNA from a species of octopus is shown in the table.
Base Adenine X Y Z
% base composition 33.2 17.6 17.5 31.7
of DNA
Which option correctly identifies bases X, Y and Z?
A Base X is cytosine, Y is guanine and Z is thymine.
B Base X is cytosine, Y is guanine and Z is uracil.
C Base X is thymine, Y is cytosine and Z is guanine.
D Base X is uracil, Y is cytosine and Z is guanine.
Your answer [1]
5 A student calculated cardiac output (CO) using the equation:
CO = heart rate × stroke volume.
What unit of measurement is appropriate for cardiac output?
A bpm cm–3
B cm3 bpm
C dm–3 min–1
D dm3 min–1
Your answer [1]
© OCR 2025 Turn over
for more: tyrionpapers.com
model answers
, Oxford Cambridge and RSA
Thursday 5 June 2025 – Afternoon
A Level Biology B (Advancing Biology)
H422/01 Fundamentals of biology
Time allowed: 2 hours 15 minutes
You must have:
* 1 8 4 8 9 0 7 1 4 4 *
• a ruler (cm/mm)
You can use:
• a scientific or graphical calculator
* H 4 2 2 0 1 *
Please write clearly in black ink. Do not write in the barcodes.
Centre number Candidate number
First name(s)
Last name
INSTRUCTIONS
• Use black ink. You can use an HB pencil, but only for graphs and diagrams.
• Write your answer to each question in the space provided. If you need extra space use
the lined pages at the end of this booklet. The question numbers must be clearly shown.
• Answer all the questions.
• Where appropriate, your answer should be supported with working. Marks might be
given for using a correct method, even if your answer is wrong.
INFORMATION
• The total mark for this paper is 110.
• The marks for each question are shown in brackets [ ].
• Quality of extended response will be assessed in questions marked with an asterisk (*).
• This document has 44 pages.
ADVICE
• Read each question carefully before you start your answer.
© OCR 2025 [601/4720/9] OCR is an exempt Charity
DC (DE/SG) 347647/4 Turn over
for more: tyrionpapers.com
, 2
Section A
You should spend a maximum of 40 minutes on this section.
Write your answer for each question in the box provided.
1 Which type of blood cell is shown in the annotated drawing?
Non-granulated cytoplasm
Kidney-bean shaped nucleus
A Erythrocyte
B Lymphocyte
C Monocyte
D Neutrophil
Your answer [1]
2 Which technique uses fluorescent markers to tag cells so they can be counted and identified
when passed through a laser beam?
A Differential staining
B Flow cytometry
C Gel electrophoresis
D Haemocytometry
Your answer [1]
© OCR 2025
for more: tyrionpapers.com
, 3
3 Which statement about ATP is not correct?
A It can be hydrolysed to form AMP.
B It contains the pentose sugar, ribose.
C It contains the pyrimidine nitrogenous base, adenine.
D It is a phosphorylated nucleotide.
Your answer [1]
4 The percentage base composition of DNA from a species of octopus is shown in the table.
Base Adenine X Y Z
% base composition 33.2 17.6 17.5 31.7
of DNA
Which option correctly identifies bases X, Y and Z?
A Base X is cytosine, Y is guanine and Z is thymine.
B Base X is cytosine, Y is guanine and Z is uracil.
C Base X is thymine, Y is cytosine and Z is guanine.
D Base X is uracil, Y is cytosine and Z is guanine.
Your answer [1]
5 A student calculated cardiac output (CO) using the equation:
CO = heart rate × stroke volume.
What unit of measurement is appropriate for cardiac output?
A bpm cm–3
B cm3 bpm
C dm–3 min–1
D dm3 min–1
Your answer [1]
© OCR 2025 Turn over
for more: tyrionpapers.com
