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 23 May 2024 Morning Time allowed: 1 hour 30 minutes
Materials
For this paper you must have: For Examiner’s Use
• 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
• Answer all questions.
• You must answer the questions in the spaces provided. Do not write 5
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).
• Show all your working. 8
• Do all rough work in this book. Cross through any work you do not want 9
to be marked.
TOTAL
Information
• The marks for the questions are shown in brackets.
• The maximum mark for this paper is 75.
*JUN247401201*
IB/M/Jun24/G4001/E7 7401/2
, 2
Do not write
outside the
Answer all questions in the spaces provided. box
0 1 . 1 Water has a high heat capacity and a large latent heat of vaporisation.
Describe the importance of each of these properties to living organisms.
[2 marks]
High heat capacity
Large latent heat of vaporisation
0 1 . 2 Figure 1 shows that water loss from a porous pot can cause the upward movement of
water.
Figure 1
*02*
IB/M/Jun24/7401/2
, 3
Do not write
outside the
Biologists have concluded that the experiment in Figure 1 supports the box
cohesion–tension theory of water transport in the xylem.
Explain how this conclusion is supported by the experiment in Figure 1.
[3 marks]
0 1 . 3 An air bubble was introduced into the glass tubing in Figure 1. The air bubble moved
a distance (d) of 1.5 cm in 120 minutes. The radius of the lumen (hole) of the glass
tubing was 0.6 cm
Use this information and the formula πr 2 d to calculate the rate of water movement in
the glass tubing in cm3 hour –1.
Use π = 3.14 in your calculation.
[1 mark]
Answer cm3 hour –1 6
Turn over ►
*03*
IB/M/Jun24/7401/2
, 4
Do not write
outside the
0 2 . 1 box
Figure 2 shows an image of a red blood cell at a magnification of × 5500
Figure 2
Calculate the actual diameter in μm of the red blood cell between points P and Q.
Show your working.
[2 marks]
Answer μm
*04*
IB/M/Jun24/7401/2
, 5
Do not write
outside the
0 2 . 2 A haemocytometer is a special microscope slide that can be used to determine the box
mean number of red blood cells in 0.004 mm3 of blood.
• A researcher prepared a 10–3 dilution of a sample of blood from an adult.
• Using a haemocytometer, the researcher determined that the mean number of red
blood cells in 0.004 mm3 of the diluted blood sample was 21
The volume of blood in the body of the adult was 4.8 dm3
Calculate the total number of red blood cells in the body of this adult.
Show your working.
[2 marks]
Answer
0 2 . 3 The solution used to dilute the blood had to have the same water potential as the
blood.
Explain why.
[2 marks]
Question 2 continues on the next page
Turn over ►
*05*
IB/M/Jun24/7401/2
, 6
Do not write
outside the
0 2 . 4 box
There are four main blood groups in the human ABO blood group system.
Table 1 shows the basis on which each of these blood groups is classified.
Table 1
Antigens present on Antibodies present in
ABO blood group
red blood cells blood plasma
A A Anti-B
B B Anti-A
AB A and B No anti-A and no anti-B
O No A and no B Anti-A and anti-B
A transfusion of blood from a blood group A donor to a blood group B recipient would
cause agglutination of the donated red blood cells.
Use information in Table 1 to explain why.
[2 marks]
0 2 . 5 Using Table 1, give the blood groups of people who could accept a donation of blood
group O without causing agglutination of the donated red blood cells.
[1 mark]
Blood groups 9
*06*
IB/M/Jun24/7401/2
Centre number Candidate number
Surname
Forename(s)
Candidate signature
I declare this is my own work.
AS
BIOLOGY
Paper 2
Thursday 23 May 2024 Morning Time allowed: 1 hour 30 minutes
Materials
For this paper you must have: For Examiner’s Use
• 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
• Answer all questions.
• You must answer the questions in the spaces provided. Do not write 5
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).
• Show all your working. 8
• Do all rough work in this book. Cross through any work you do not want 9
to be marked.
TOTAL
Information
• The marks for the questions are shown in brackets.
• The maximum mark for this paper is 75.
*JUN247401201*
IB/M/Jun24/G4001/E7 7401/2
, 2
Do not write
outside the
Answer all questions in the spaces provided. box
0 1 . 1 Water has a high heat capacity and a large latent heat of vaporisation.
Describe the importance of each of these properties to living organisms.
[2 marks]
High heat capacity
Large latent heat of vaporisation
0 1 . 2 Figure 1 shows that water loss from a porous pot can cause the upward movement of
water.
Figure 1
*02*
IB/M/Jun24/7401/2
, 3
Do not write
outside the
Biologists have concluded that the experiment in Figure 1 supports the box
cohesion–tension theory of water transport in the xylem.
Explain how this conclusion is supported by the experiment in Figure 1.
[3 marks]
0 1 . 3 An air bubble was introduced into the glass tubing in Figure 1. The air bubble moved
a distance (d) of 1.5 cm in 120 minutes. The radius of the lumen (hole) of the glass
tubing was 0.6 cm
Use this information and the formula πr 2 d to calculate the rate of water movement in
the glass tubing in cm3 hour –1.
Use π = 3.14 in your calculation.
[1 mark]
Answer cm3 hour –1 6
Turn over ►
*03*
IB/M/Jun24/7401/2
, 4
Do not write
outside the
0 2 . 1 box
Figure 2 shows an image of a red blood cell at a magnification of × 5500
Figure 2
Calculate the actual diameter in μm of the red blood cell between points P and Q.
Show your working.
[2 marks]
Answer μm
*04*
IB/M/Jun24/7401/2
, 5
Do not write
outside the
0 2 . 2 A haemocytometer is a special microscope slide that can be used to determine the box
mean number of red blood cells in 0.004 mm3 of blood.
• A researcher prepared a 10–3 dilution of a sample of blood from an adult.
• Using a haemocytometer, the researcher determined that the mean number of red
blood cells in 0.004 mm3 of the diluted blood sample was 21
The volume of blood in the body of the adult was 4.8 dm3
Calculate the total number of red blood cells in the body of this adult.
Show your working.
[2 marks]
Answer
0 2 . 3 The solution used to dilute the blood had to have the same water potential as the
blood.
Explain why.
[2 marks]
Question 2 continues on the next page
Turn over ►
*05*
IB/M/Jun24/7401/2
, 6
Do not write
outside the
0 2 . 4 box
There are four main blood groups in the human ABO blood group system.
Table 1 shows the basis on which each of these blood groups is classified.
Table 1
Antigens present on Antibodies present in
ABO blood group
red blood cells blood plasma
A A Anti-B
B B Anti-A
AB A and B No anti-A and no anti-B
O No A and no B Anti-A and anti-B
A transfusion of blood from a blood group A donor to a blood group B recipient would
cause agglutination of the donated red blood cells.
Use information in Table 1 to explain why.
[2 marks]
0 2 . 5 Using Table 1, give the blood groups of people who could accept a donation of blood
group O without causing agglutination of the donated red blood cells.
[1 mark]
Blood groups 9
*06*
IB/M/Jun24/7401/2
