A-level
BIOLOGY
Paper 2
Friday 14 June 2024 Morning Time allowed: 2 hours
For Examiner’s Use
Question Mark
1
2
3
4
5
6
7
8
9
10
TOTAL
7402/2
, 2
Do not write
outside the
Answer all questions in the spaces provided. box
0 1 Figure 1 shows a drawing of a neuromuscular junction.
Figure 1
0 1 . 1 Name the parts labelled A to D.
[2 marks]
A
B
C
D
, 3
0 1 . 2 Following the release of acetylcholine into a neuromuscular junction, a muscle
contraction occurs.
Describe the sequence of events, following the release of acetylcholine, that leads to
stimulation of this contraction.
Do not include in your answer the events following the release of calcium ions in the
myofibril.
[4 marks]
0 1 . 3 Inhibitory synapses cause hyperpolarisation in postsynaptic neurones.
Explain how this inhibits synaptic transmission.
[2 marks]
8
Turn over ►
, 4
Do not write
outside the
0 2 . 1 Figure 2 shows part of a relaxed myofibril. box
Figure 2
The myofibril represented in Figure 2 has 34 sarcomeres.
The length of every sarcomere is 2 µm
After contraction of this myofibril, the length of each sarcomere changed by 20%.
Use the information provided to calculate the length of the myofibril after contraction.
Give your answer in mm and in standard form.
Show your working.
[2 marks]
Answer mm
BIOLOGY
Paper 2
Friday 14 June 2024 Morning Time allowed: 2 hours
For Examiner’s Use
Question Mark
1
2
3
4
5
6
7
8
9
10
TOTAL
7402/2
, 2
Do not write
outside the
Answer all questions in the spaces provided. box
0 1 Figure 1 shows a drawing of a neuromuscular junction.
Figure 1
0 1 . 1 Name the parts labelled A to D.
[2 marks]
A
B
C
D
, 3
0 1 . 2 Following the release of acetylcholine into a neuromuscular junction, a muscle
contraction occurs.
Describe the sequence of events, following the release of acetylcholine, that leads to
stimulation of this contraction.
Do not include in your answer the events following the release of calcium ions in the
myofibril.
[4 marks]
0 1 . 3 Inhibitory synapses cause hyperpolarisation in postsynaptic neurones.
Explain how this inhibits synaptic transmission.
[2 marks]
8
Turn over ►
, 4
Do not write
outside the
0 2 . 1 Figure 2 shows part of a relaxed myofibril. box
Figure 2
The myofibril represented in Figure 2 has 34 sarcomeres.
The length of every sarcomere is 2 µm
After contraction of this myofibril, the length of each sarcomere changed by 20%.
Use the information provided to calculate the length of the myofibril after contraction.
Give your answer in mm and in standard form.
Show your working.
[2 marks]
Answer mm
