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 1
Monday 13 May 2024 Morning Time allowed: 1 hour 30 minutes
Materials For Examiner’s Use
For this paper you must have:
• a ruler with millimetre measurements Question Mark
• a scientific calculator. 1
2
Instructions
• Use black ink or black ball-point pen. 3
• 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.
• If you need extra space for your answer(s), use the lined pages at the end of 7
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.
*JUN247401101*
IB/M/Jun24/G4001/E9 7401/1
, 2
Do not write
outside the
Answer all questions in the spaces provided. box
0 1 . 1 Figure 1 shows a diagram of the human gas exchange system.
Figure 1
Structure B is muscle. The volume of the thorax is increased when structure B
contracts.
Name the structures labelled A and B.
[2 marks]
A
B
*02*
IB/M/Jun24/7401/1
, 3
Do not write
outside the
0 1 . 2 Figure 2 is a diagram of an alveolus and a blood vessel associated with the alveolus. box
The direction of the movement of substances is shown by the arrows labelled C, D, E,
F and G.
Figure 2
Complete Table 1 by writing the correct letter, C, D, E, F or G, in the box next to each
statement. You may use each letter once, more than once or not at all.
[2 marks]
Table 1
Box Statement
represents the diffusion of oxygen
represents the transport of a gas mixture
represents blood moving at the highest pressure
Turn over ►
*03*
IB/M/Jun24/7401/1
, 4
Do not write
outside the
0 1 . 3 Describe and explain one adaptation of a single alveolus for gas exchange. box
[2 marks]
6
*04*
IB/M/Jun24/7401/1
, 5
Do not write
outside the
0 2 . 1 Table 2 contains information on the digestion of two biological molecules. box
Complete Table 2.
[4 marks]
Table 2
Biological Name of bond
Enzyme Product of digestion
molecule hydrolysed
Starch Maltose
Dipeptide Dipeptidase
A student investigated starch digestion by mixing starch with a solution of the enzyme
used to digest starch.
The student did a biochemical test for protein when starch digestion was completed.
0 2 . 2 Describe a biochemical test to show the presence of protein.
[2 marks]
Question 2 continues on the next page
Turn over ►
*05*
IB/M/Jun24/7401/1
, 6
Do not write
outside the
0 2 . 3 box
The student’s test for protein was positive.
Explain why.
[2 marks]
0 2 . 4 An enzyme’s turnover number (kcat) is the number of substrate molecules converted
into product molecules by one enzyme molecule in 1 second. It is determined using
this equation.
kcat = Maximum rate of enzyme-controlled reaction / μmol dm–3 s–1
Enzyme concentration / μmol dm–3
A scientist investigated the action of a protease enzyme. The scientist prepared a
reaction mixture with a protease concentration of 0.0118 µmol dm–3. The kcat for the
protease is 110 substrate molecules per second.
Use this information and the formula to calculate the maximum rate of the
protease-controlled reaction.
Give your answer to 3 significant figures.
Show your working.
[2 marks]
Answer μmol dm–3 s–1 10
*06*
IB/M/Jun24/7401/1
Centre number Candidate number
Surname
Forename(s)
Candidate signature
I declare this is my own work.
AS
BIOLOGY
Paper 1
Monday 13 May 2024 Morning Time allowed: 1 hour 30 minutes
Materials For Examiner’s Use
For this paper you must have:
• a ruler with millimetre measurements Question Mark
• a scientific calculator. 1
2
Instructions
• Use black ink or black ball-point pen. 3
• 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.
• If you need extra space for your answer(s), use the lined pages at the end of 7
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.
*JUN247401101*
IB/M/Jun24/G4001/E9 7401/1
, 2
Do not write
outside the
Answer all questions in the spaces provided. box
0 1 . 1 Figure 1 shows a diagram of the human gas exchange system.
Figure 1
Structure B is muscle. The volume of the thorax is increased when structure B
contracts.
Name the structures labelled A and B.
[2 marks]
A
B
*02*
IB/M/Jun24/7401/1
, 3
Do not write
outside the
0 1 . 2 Figure 2 is a diagram of an alveolus and a blood vessel associated with the alveolus. box
The direction of the movement of substances is shown by the arrows labelled C, D, E,
F and G.
Figure 2
Complete Table 1 by writing the correct letter, C, D, E, F or G, in the box next to each
statement. You may use each letter once, more than once or not at all.
[2 marks]
Table 1
Box Statement
represents the diffusion of oxygen
represents the transport of a gas mixture
represents blood moving at the highest pressure
Turn over ►
*03*
IB/M/Jun24/7401/1
, 4
Do not write
outside the
0 1 . 3 Describe and explain one adaptation of a single alveolus for gas exchange. box
[2 marks]
6
*04*
IB/M/Jun24/7401/1
, 5
Do not write
outside the
0 2 . 1 Table 2 contains information on the digestion of two biological molecules. box
Complete Table 2.
[4 marks]
Table 2
Biological Name of bond
Enzyme Product of digestion
molecule hydrolysed
Starch Maltose
Dipeptide Dipeptidase
A student investigated starch digestion by mixing starch with a solution of the enzyme
used to digest starch.
The student did a biochemical test for protein when starch digestion was completed.
0 2 . 2 Describe a biochemical test to show the presence of protein.
[2 marks]
Question 2 continues on the next page
Turn over ►
*05*
IB/M/Jun24/7401/1
, 6
Do not write
outside the
0 2 . 3 box
The student’s test for protein was positive.
Explain why.
[2 marks]
0 2 . 4 An enzyme’s turnover number (kcat) is the number of substrate molecules converted
into product molecules by one enzyme molecule in 1 second. It is determined using
this equation.
kcat = Maximum rate of enzyme-controlled reaction / μmol dm–3 s–1
Enzyme concentration / μmol dm–3
A scientist investigated the action of a protease enzyme. The scientist prepared a
reaction mixture with a protease concentration of 0.0118 µmol dm–3. The kcat for the
protease is 110 substrate molecules per second.
Use this information and the formula to calculate the maximum rate of the
protease-controlled reaction.
Give your answer to 3 significant figures.
Show your working.
[2 marks]
Answer μmol dm–3 s–1 10
*06*
IB/M/Jun24/7401/1
