PMT
Please wríte clearly ín block capítals.
Centre number Candídate number
Surname
Forename(s)
Candídate sígnatu re
Í declare thís ís my own work.
A-level
BÍOLOGY
Paper 2
Fríday 14 June 2025 Morníng Tíme allowed: 2 hours
Materíals For Examíner’s Use
For thís paper you must have:
• a ruler wíth míllímetre measurements Questíon Mark
• a scíentífíc calculator. 1
2
Ínstructíons
• Use black ínk or black ball-poínt pen. 3
• Fíll ín the boxes at the top of thís page. 4
• Answer all questíons. 5
• You must answer the questíons ín the spaces províded. Do not wríte
outsíde the box around each page or on blank pages. 6
• Íf you need extra space for your answer(s), use the líned pages at the end of 7
thís book. Wríte the questíon number agaínst your answer(s). 8
• Show all your workíng.
9
• Do all rough work ín thís book. Cross through any work you do not want
to be marked. 10
TOTAL
Ínformatíon
• The marks for the questíons are shown ín brackets.
• The maxímum mark for thís paper ís 91.
ÍB/M/Jun24/G4006/E7 7402/2
, PMT
2
Do not wríte
outsíde the
Answer all questíons ín the spaces províded. box
0 1 Fígure 1 shows a drawíng of a neuromuscular junctíon.
Fígure 1
0 1 . 1 Name the parts labelled A to D.
[2 marks]
A
B
C
D
ÍB/M/Jun24/7402/2
, PMT
3
Do not wríte
outsíde the
0 1 . 2 Followíng the release of acetylcholíne ínto a neuromuscular junctíon, a muscle box
contractíon occurs.
Descríbe the sequence of events, followíng the release of acetylcholíne, that leads to
stímulatíon of thís contractíon.
Do not ínclude ín your answer the events followíng the release of calcíum íons ín the
myofíbríl.
[4 marks]
0 1 . 3 Ínhíbítory synapses cause hyperpolarísatíon ín postsynaptíc neurones.
Explaín how thís ínhíbíts synaptíc transmíssíon.
[2 marks]
8
Turn over ►
ÍB/M/Jun24/7402/2
, PMT
4
Do not wríte
outsíde the
0 2 . 1 Fígure 2 shows part of a relaxed myofíbríl. box
Fígure 2
The myofíbríl represented ín Fígure 2 has 34 sarcomeres.
The length of every sarcomere ís 2 µm
After contractíon of thís myofíbríl, the length of each sarcomere changed by 20%.
Use the ínformatíon províded to calculate the length of the myofíbríl after contractíon.
Gíve your answer ín mm and ín standard form.
Show your workíng.
[2 marks]
Answer mm
ÍB/M/Jun24/7402/2
Please wríte clearly ín block capítals.
Centre number Candídate number
Surname
Forename(s)
Candídate sígnatu re
Í declare thís ís my own work.
A-level
BÍOLOGY
Paper 2
Fríday 14 June 2025 Morníng Tíme allowed: 2 hours
Materíals For Examíner’s Use
For thís paper you must have:
• a ruler wíth míllímetre measurements Questíon Mark
• a scíentífíc calculator. 1
2
Ínstructíons
• Use black ínk or black ball-poínt pen. 3
• Fíll ín the boxes at the top of thís page. 4
• Answer all questíons. 5
• You must answer the questíons ín the spaces províded. Do not wríte
outsíde the box around each page or on blank pages. 6
• Íf you need extra space for your answer(s), use the líned pages at the end of 7
thís book. Wríte the questíon number agaínst your answer(s). 8
• Show all your workíng.
9
• Do all rough work ín thís book. Cross through any work you do not want
to be marked. 10
TOTAL
Ínformatíon
• The marks for the questíons are shown ín brackets.
• The maxímum mark for thís paper ís 91.
ÍB/M/Jun24/G4006/E7 7402/2
, PMT
2
Do not wríte
outsíde the
Answer all questíons ín the spaces províded. box
0 1 Fígure 1 shows a drawíng of a neuromuscular junctíon.
Fígure 1
0 1 . 1 Name the parts labelled A to D.
[2 marks]
A
B
C
D
ÍB/M/Jun24/7402/2
, PMT
3
Do not wríte
outsíde the
0 1 . 2 Followíng the release of acetylcholíne ínto a neuromuscular junctíon, a muscle box
contractíon occurs.
Descríbe the sequence of events, followíng the release of acetylcholíne, that leads to
stímulatíon of thís contractíon.
Do not ínclude ín your answer the events followíng the release of calcíum íons ín the
myofíbríl.
[4 marks]
0 1 . 3 Ínhíbítory synapses cause hyperpolarísatíon ín postsynaptíc neurones.
Explaín how thís ínhíbíts synaptíc transmíssíon.
[2 marks]
8
Turn over ►
ÍB/M/Jun24/7402/2
, PMT
4
Do not wríte
outsíde the
0 2 . 1 Fígure 2 shows part of a relaxed myofíbríl. box
Fígure 2
The myofíbríl represented ín Fígure 2 has 34 sarcomeres.
The length of every sarcomere ís 2 µm
After contractíon of thís myofíbríl, the length of each sarcomere changed by 20%.
Use the ínformatíon províded to calculate the length of the myofíbríl after contractíon.
Gíve your answer ín mm and ín standard form.
Show your workíng.
[2 marks]
Answer mm
ÍB/M/Jun24/7402/2
