Oxford Cambridge and RSA
GCSE
Biology A
*1442234452*
H020/01: Breadth in biology
AS Level
Monday 12 May 2025 – Morning
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 70.
• The marks for each question are shown in brackets [ ].
• This document has 28 pages.
ADVICE
• Read each question carefully before you start your answer.
© OCR 2025 [601/4261/3 ] DC (PQ/CB) 345878/5
OCR is an exempt Charity
Turn over
Section A
You should spend a maximum of 25 minutes on this section.
Write your answer for each question in the box provided.
1 Which statement correctly describes microscopes?
A Light microscopes can produce higher resolution images than electron
microscopes.
B Scanning electron microscopes produce higher resolution images than
transmission electron microscopes.
, 2
C Transmission electron microscopes can achieve higher magnifications than
scanning electron microscopes.
D Transmission electron microscopes can be used to view living tissues.
Your answer
2 Which statement correctly describes phosphorylated nucleotides?
A ADP can be hydrolysed to produce ATP.
B ADP can be phosphorylated to produce ATP.
C All phosphorylated nucleotides have three phosphate groups.
D Energy is released when ATP undergoes a condensation reaction to form ADP
and Pi.
Your answer
3 Which type of stem cell can become specialised into more than one cell type but is
limited to a range of cell types?
A Embryonic
B Multipotent
C Pluripotent
D Totipotent
Your answer
4 A student carries out a non-reducing sugar test on a sample of fruit juice.
What is the correct reason for heating the sample with hydrochloric acid?
A It breaks the ester bond between glucose and fructose
B It breaks the ester bond between glucose and sucrose
C It breaks the glycosidic bond between glucose and fructose
D It breaks the glycosidic bond between glucose and sucrose
© OCR 2025
, 3
Your answer
© OCR 2025 Turn over
, 4
5 A student is finding out the concentration of a sample of protein.
• They set up five solutions that have a range of different protein concentrations.
• They carry out a chemical test on each solution that produces a colour change.
• They use a colorimeter to find out the absorbance of light through each solution.
The graph shows the calibration curve they plotted for each concentration of protein.
0.20
0.18
0.16
0.14
0.12
Absorbance
(arbitrary units) 0.10
0.08
0.06
0.04
0.02
0.00
0.0 0.5 1.0 1.5 2.0 2.5
Percentage concentration of protein
They carry out the same chemical test on the sample of protein with the unknown
concentration and measure the absorbance as 0.16 arbitrary units.
Which statement correctly describes the results of the experiment?
A The concentration of protein in the sample tested is 1.6%.
B The concentration of protein in the sample tested is too low to read from the
graph.
C The greater the concentration of protein, the less light is absorbed by the sample.
D The greater the concentration of protein, the less light is transmitted through the
sample.
Your answer
The diagram shows the structure of a cell surface membrane.
Use the diagram to answer questions 6 and 7.
© OCR 2025
GCSE
Biology A
*1442234452*
H020/01: Breadth in biology
AS Level
Monday 12 May 2025 – Morning
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 70.
• The marks for each question are shown in brackets [ ].
• This document has 28 pages.
ADVICE
• Read each question carefully before you start your answer.
© OCR 2025 [601/4261/3 ] DC (PQ/CB) 345878/5
OCR is an exempt Charity
Turn over
Section A
You should spend a maximum of 25 minutes on this section.
Write your answer for each question in the box provided.
1 Which statement correctly describes microscopes?
A Light microscopes can produce higher resolution images than electron
microscopes.
B Scanning electron microscopes produce higher resolution images than
transmission electron microscopes.
, 2
C Transmission electron microscopes can achieve higher magnifications than
scanning electron microscopes.
D Transmission electron microscopes can be used to view living tissues.
Your answer
2 Which statement correctly describes phosphorylated nucleotides?
A ADP can be hydrolysed to produce ATP.
B ADP can be phosphorylated to produce ATP.
C All phosphorylated nucleotides have three phosphate groups.
D Energy is released when ATP undergoes a condensation reaction to form ADP
and Pi.
Your answer
3 Which type of stem cell can become specialised into more than one cell type but is
limited to a range of cell types?
A Embryonic
B Multipotent
C Pluripotent
D Totipotent
Your answer
4 A student carries out a non-reducing sugar test on a sample of fruit juice.
What is the correct reason for heating the sample with hydrochloric acid?
A It breaks the ester bond between glucose and fructose
B It breaks the ester bond between glucose and sucrose
C It breaks the glycosidic bond between glucose and fructose
D It breaks the glycosidic bond between glucose and sucrose
© OCR 2025
, 3
Your answer
© OCR 2025 Turn over
, 4
5 A student is finding out the concentration of a sample of protein.
• They set up five solutions that have a range of different protein concentrations.
• They carry out a chemical test on each solution that produces a colour change.
• They use a colorimeter to find out the absorbance of light through each solution.
The graph shows the calibration curve they plotted for each concentration of protein.
0.20
0.18
0.16
0.14
0.12
Absorbance
(arbitrary units) 0.10
0.08
0.06
0.04
0.02
0.00
0.0 0.5 1.0 1.5 2.0 2.5
Percentage concentration of protein
They carry out the same chemical test on the sample of protein with the unknown
concentration and measure the absorbance as 0.16 arbitrary units.
Which statement correctly describes the results of the experiment?
A The concentration of protein in the sample tested is 1.6%.
B The concentration of protein in the sample tested is too low to read from the
graph.
C The greater the concentration of protein, the less light is absorbed by the sample.
D The greater the concentration of protein, the less light is transmitted through the
sample.
Your answer
The diagram shows the structure of a cell surface membrane.
Use the diagram to answer questions 6 and 7.
© OCR 2025
