Please write clearly in block capitals.
Centre number Candidate number
Surname
Forename(s)
Candidate signature
I declare this is my own work.
AS
BIOLOGY
Paper 2
Thursday 21 May 2026 Morning Time allowed: 1 hour 30 minutes
Materials For Examiner’s Use
For this paper you must have:
Question Mark
• a ruler with millimetre measurements
• a scientific calculator. 1
2
Instructions
3
• Use black ink or black ball-point pen.
• Fill in the boxes at the top of this page. 4
• Answer all questions. 5
• You must answer the questions in the spaces provided. Do not write 6
outside the box around each page or on blank pages.
7
• If you need extra space for your answer(s), use the lined pages at the end of
this book. Write the question number against your answer(s). 8
• Show all your working. 9
• Do all rough work in this book. Cross through any work you do not want
to be marked. TOTAL
Information
• The marks for the questions are shown in brackets.
• The maximum mark for this paper is 75.
*jun *
IB/M/Jun26/G4003/V5 7401/2
, 2
Do not write
outside the
Answer all questions in the spaces provided. box
0 1 . 1 In the following passage, each numbered space can be filled with a biological term.
A gene is a sequence of bases in DNA that codes for the sequence of amino acids in
a polypeptide. A gene also codes for a functional (1) molecule.
A polypeptide folds into its secondary structure, held in place by (2) bonds
which also occur in the tertiary structure. The tertiary structure of a protein can be
maintained by (3) bridges and (4) bonds.
Write the correct biological term beside each number below so that it matches the
numbered space in the passage.
[2 marks]
1
2
3
4
*02*
IB/M/Jun26/7401/2
, 3
Do not write
outside the
0 1 . 2 Enzymes are proteins that control the rate of reactions. box
Figure 1 shows the progress of a reaction without an enzyme.
Figure 1
Draw a line on Figure 1 to show the progress of the same reaction with an enzyme.
[2 marks]
0 1 . 3 Formation of an enzyme-substrate complex increases the rate of reaction.
Explain how.
[2 marks]
6
Turn over ►
*03*
IB/M/Jun26/7401/2
, 4
Do not write
outside the
0 2 Cells from a garlic root can be used to observe mitosis. box
A student wrote a method for preparing a microscope slide of garlic root cells:
1. Cut a section of garlic root and place it on a glass slide.
2. Add a drop of water to the slide.
3. Lay a cover slip on top of the section of root.
4. Observe the section of root under the microscope.
0 2 . 1 Suggest and explain two improvements to the method which are needed to obtain a
slide of cells suitable for observing mitosis.
[4 marks]
Improvement 1
Explanation 1
Improvement 2
Explanation 2
*04*
IB/M/Jun26/7401/2
Centre number Candidate number
Surname
Forename(s)
Candidate signature
I declare this is my own work.
AS
BIOLOGY
Paper 2
Thursday 21 May 2026 Morning Time allowed: 1 hour 30 minutes
Materials For Examiner’s Use
For this paper you must have:
Question Mark
• a ruler with millimetre measurements
• a scientific calculator. 1
2
Instructions
3
• Use black ink or black ball-point pen.
• Fill in the boxes at the top of this page. 4
• Answer all questions. 5
• You must answer the questions in the spaces provided. Do not write 6
outside the box around each page or on blank pages.
7
• If you need extra space for your answer(s), use the lined pages at the end of
this book. Write the question number against your answer(s). 8
• Show all your working. 9
• Do all rough work in this book. Cross through any work you do not want
to be marked. TOTAL
Information
• The marks for the questions are shown in brackets.
• The maximum mark for this paper is 75.
*jun *
IB/M/Jun26/G4003/V5 7401/2
, 2
Do not write
outside the
Answer all questions in the spaces provided. box
0 1 . 1 In the following passage, each numbered space can be filled with a biological term.
A gene is a sequence of bases in DNA that codes for the sequence of amino acids in
a polypeptide. A gene also codes for a functional (1) molecule.
A polypeptide folds into its secondary structure, held in place by (2) bonds
which also occur in the tertiary structure. The tertiary structure of a protein can be
maintained by (3) bridges and (4) bonds.
Write the correct biological term beside each number below so that it matches the
numbered space in the passage.
[2 marks]
1
2
3
4
*02*
IB/M/Jun26/7401/2
, 3
Do not write
outside the
0 1 . 2 Enzymes are proteins that control the rate of reactions. box
Figure 1 shows the progress of a reaction without an enzyme.
Figure 1
Draw a line on Figure 1 to show the progress of the same reaction with an enzyme.
[2 marks]
0 1 . 3 Formation of an enzyme-substrate complex increases the rate of reaction.
Explain how.
[2 marks]
6
Turn over ►
*03*
IB/M/Jun26/7401/2
, 4
Do not write
outside the
0 2 Cells from a garlic root can be used to observe mitosis. box
A student wrote a method for preparing a microscope slide of garlic root cells:
1. Cut a section of garlic root and place it on a glass slide.
2. Add a drop of water to the slide.
3. Lay a cover slip on top of the section of root.
4. Observe the section of root under the microscope.
0 2 . 1 Suggest and explain two improvements to the method which are needed to obtain a
slide of cells suitable for observing mitosis.
[4 marks]
Improvement 1
Explanation 1
Improvement 2
Explanation 2
*04*
IB/M/Jun26/7401/2
