000001
Please write clearly in block capitals.
Centre number Candidate number
Surname
Forename(s)
Candidate signature
I declare this is my own work.
T
A-level
ES
BIOLOGY
Paper 1 B
Wednesday 5 June 2024 Afternoon Time allowed: 2 hours
E
Materials
For Examiner’s Use
For this paper you must have:
TH
• a ruler with millimetre measurements Question Mark
• a scientific calculator.
1
Instructions 2
• Use black ink or black ball-point pen. 3
• Fill in the boxes at the top of this page. 4
LL
• Answer all questions.
5
• You must answer the questions in the spaces provided. Do not write
outside the box around each page or on blank pages. 6
• 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).
A
8
• Show all your working.
• Do all rough work in this book. Cross through any work you do not want 9
to be marked. 10
TOTAL
Information
• The marks for the questions are shown in brackets.
• The maximum mark for this paper is 91.
*jun247402101*
IB/M/Jun24/G4006/E11 7402/1
Page 1 of 32
,000002
2
Do not write
outside the
Answer all questions in the spaces provided. box
0 1 . 1 Figure 1 shows the structure of a fatty acid molecule and the structure of a glycerol
molecule.
Figure 1
T
ES
On Figure 1, draw a circle around the part of the fatty acid molecule and the part of
the glycerol molecule that is removed to form a bond in a triglyceride molecule.
Name the bond formed between a fatty acid and glycerol in a triglyceride molecule.
triglyceride molecule.
B
Name the reaction involved in forming a bond between a fatty acid and glycerol in a
[3 marks]
E
Bond
Reaction
TH
LL
A
*02*
IB/M/Jun24/7402/1
Page 2 of 32
,000003
3
Do not write
outside the
Table 1 shows information about three fatty acids. box
Table 1
T
ES
0 1 . 2
B
Name the fatty acid shown in Table 1 that is a saturated fatty acid.
[1 mark]
E
TH
0 1 . 3 The melting point is the temperature at which a solid changes state to be a liquid.
Use Table 1 to describe the relationship between fatty acid structure and fatty acid
melting point.
[1 mark]
LL
A
Question 1 continues on the next page
Turn over ►
*03*
IB/M/Jun24/7402/1
Page 3 of 32
, 000004
4
Do not write
outside the
0 1 . 4 The ratio of saturated to unsaturated fatty acids in a cell-surface membrane box
determines the extent of the membrane’s fluidity.
Scientists provided a cell culture of mouse phagocytes with liquid broth rich in
unsaturated fatty acids.
The scientists observed:
• an increase in the proportion of phospholipids in the phagocytes containing
unsaturated fatty acids
• more phagocytosis.
Suggest and explain why there was more phagocytosis.
[3 marks]
T
ES
B
E
TH
8
LL
A
*04*
IB/M/Jun24/7402/1
Page 4 of 32
Please write clearly in block capitals.
Centre number Candidate number
Surname
Forename(s)
Candidate signature
I declare this is my own work.
T
A-level
ES
BIOLOGY
Paper 1 B
Wednesday 5 June 2024 Afternoon Time allowed: 2 hours
E
Materials
For Examiner’s Use
For this paper you must have:
TH
• a ruler with millimetre measurements Question Mark
• a scientific calculator.
1
Instructions 2
• Use black ink or black ball-point pen. 3
• Fill in the boxes at the top of this page. 4
LL
• Answer all questions.
5
• You must answer the questions in the spaces provided. Do not write
outside the box around each page or on blank pages. 6
• 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).
A
8
• Show all your working.
• Do all rough work in this book. Cross through any work you do not want 9
to be marked. 10
TOTAL
Information
• The marks for the questions are shown in brackets.
• The maximum mark for this paper is 91.
*jun247402101*
IB/M/Jun24/G4006/E11 7402/1
Page 1 of 32
,000002
2
Do not write
outside the
Answer all questions in the spaces provided. box
0 1 . 1 Figure 1 shows the structure of a fatty acid molecule and the structure of a glycerol
molecule.
Figure 1
T
ES
On Figure 1, draw a circle around the part of the fatty acid molecule and the part of
the glycerol molecule that is removed to form a bond in a triglyceride molecule.
Name the bond formed between a fatty acid and glycerol in a triglyceride molecule.
triglyceride molecule.
B
Name the reaction involved in forming a bond between a fatty acid and glycerol in a
[3 marks]
E
Bond
Reaction
TH
LL
A
*02*
IB/M/Jun24/7402/1
Page 2 of 32
,000003
3
Do not write
outside the
Table 1 shows information about three fatty acids. box
Table 1
T
ES
0 1 . 2
B
Name the fatty acid shown in Table 1 that is a saturated fatty acid.
[1 mark]
E
TH
0 1 . 3 The melting point is the temperature at which a solid changes state to be a liquid.
Use Table 1 to describe the relationship between fatty acid structure and fatty acid
melting point.
[1 mark]
LL
A
Question 1 continues on the next page
Turn over ►
*03*
IB/M/Jun24/7402/1
Page 3 of 32
, 000004
4
Do not write
outside the
0 1 . 4 The ratio of saturated to unsaturated fatty acids in a cell-surface membrane box
determines the extent of the membrane’s fluidity.
Scientists provided a cell culture of mouse phagocytes with liquid broth rich in
unsaturated fatty acids.
The scientists observed:
• an increase in the proportion of phospholipids in the phagocytes containing
unsaturated fatty acids
• more phagocytosis.
Suggest and explain why there was more phagocytosis.
[3 marks]
T
ES
B
E
TH
8
LL
A
*04*
IB/M/Jun24/7402/1
Page 4 of 32
