AcePapers
A Level Biology B (Edexcel specification 9BI0)
General & Practical Principles in Biology
(Paper 3)
Practice question paper
Practice for 9BI0 Paper 3
Time allowed 2 hours 30 minutes
Total marks 120
Equipment Calculator, ruler, HB pencil
Before you start
• Write in black ink. A pencil may be used for graphs and drawings.
• Attempt every question and write each answer in the space below it; you may not need
all of the space.
• The number of marks for each part is given in brackets. Use it to judge how much to
write and how long to spend.
• Questions labelled with an asterisk (*) also reward a clear, logically sequenced answer in
which your points are connected.
• Show your working in calculations and give units where they are needed.
• Leave time at the end to read through your answers.
• A statistics and formulae sheet is printed at the back of this paper.
Written by AcePapers
Independent practice paper written for revision. Not an official Pearson paper
and not affiliated with or endorsed by Pearson.
AcePapers · 9BI0 Paper 3 · independent practice material Page 1
, Answer every question. Where a multiple-choice question has boxes, mark your chosen answer with a
cross. To change it, draw a line through the cross and mark the new box.
1 A student investigated the effect of trypsin concentration on the rate of hydrolysis of
casein in a milk suspension. The milk suspension is cloudy and becomes clear when the
casein is broken down. The student recorded the time taken for each mixture to
become clear.
(a) Give the independent variable and the dependent variable in this
investigation. (1)
Trypsin concentration / % 0.2 0.4 0.6 0.8 1.0
Mean time to clear / s 312 158 104 80 63
(b) Calculate the rate of reaction, as 1000 ÷ time, for the 0.6 % trypsin
solution. (1)
Rate = ................................................ s−1
(c) Explain why the rate of reaction increases as trypsin concentration
increases. (2)
(d) Describe how the student should control temperature in this investigation
and explain why this is necessary. (2)
(e) Suggest how the student could make the end point of the reaction less
subjective. (1)
AcePapers · 9BI0 Paper 3 · independent practice material Page 2
, (f) Give one safety precaution needed when handling trypsin solution. (1)
[Question 1: 8 marks]
2 A student used a light microscope to observe onion epidermis cells.
(a) At ×400 magnification, 40 divisions of the eyepiece graticule lined up with
100 µm on a stage micrometer. One onion cell was 24 eyepiece divisions
long. Calculate the actual length of the cell. (2)
= ................................................ µm
(b) Describe how the student should prepare a temporary mount of onion
epidermis stained with iodine solution. (3)
(c) Give two features visible in these cells that show they are plant cells. (2)
(d) Explain why iodine solution is used. (1)
AcePapers · 9BI0 Paper 3 · independent practice material Page 3
A Level Biology B (Edexcel specification 9BI0)
General & Practical Principles in Biology
(Paper 3)
Practice question paper
Practice for 9BI0 Paper 3
Time allowed 2 hours 30 minutes
Total marks 120
Equipment Calculator, ruler, HB pencil
Before you start
• Write in black ink. A pencil may be used for graphs and drawings.
• Attempt every question and write each answer in the space below it; you may not need
all of the space.
• The number of marks for each part is given in brackets. Use it to judge how much to
write and how long to spend.
• Questions labelled with an asterisk (*) also reward a clear, logically sequenced answer in
which your points are connected.
• Show your working in calculations and give units where they are needed.
• Leave time at the end to read through your answers.
• A statistics and formulae sheet is printed at the back of this paper.
Written by AcePapers
Independent practice paper written for revision. Not an official Pearson paper
and not affiliated with or endorsed by Pearson.
AcePapers · 9BI0 Paper 3 · independent practice material Page 1
, Answer every question. Where a multiple-choice question has boxes, mark your chosen answer with a
cross. To change it, draw a line through the cross and mark the new box.
1 A student investigated the effect of trypsin concentration on the rate of hydrolysis of
casein in a milk suspension. The milk suspension is cloudy and becomes clear when the
casein is broken down. The student recorded the time taken for each mixture to
become clear.
(a) Give the independent variable and the dependent variable in this
investigation. (1)
Trypsin concentration / % 0.2 0.4 0.6 0.8 1.0
Mean time to clear / s 312 158 104 80 63
(b) Calculate the rate of reaction, as 1000 ÷ time, for the 0.6 % trypsin
solution. (1)
Rate = ................................................ s−1
(c) Explain why the rate of reaction increases as trypsin concentration
increases. (2)
(d) Describe how the student should control temperature in this investigation
and explain why this is necessary. (2)
(e) Suggest how the student could make the end point of the reaction less
subjective. (1)
AcePapers · 9BI0 Paper 3 · independent practice material Page 2
, (f) Give one safety precaution needed when handling trypsin solution. (1)
[Question 1: 8 marks]
2 A student used a light microscope to observe onion epidermis cells.
(a) At ×400 magnification, 40 divisions of the eyepiece graticule lined up with
100 µm on a stage micrometer. One onion cell was 24 eyepiece divisions
long. Calculate the actual length of the cell. (2)
= ................................................ µm
(b) Describe how the student should prepare a temporary mount of onion
epidermis stained with iodine solution. (3)
(c) Give two features visible in these cells that show they are plant cells. (2)
(d) Explain why iodine solution is used. (1)
AcePapers · 9BI0 Paper 3 · independent practice material Page 3
