aqa
Please write clearly in block capitals.
Centre Candidate
number number
Surname
Forename(s)
Candidate re
signatu
A-level
BIOLOGY
Paper 3
7402/3
Wednesday 21 June 2023 Morning Time allowed: 2 hours
Materials
For this paper you must have: For Examiner’s Use
a ruler with millimetre measurements
Questio Mark
a scientific calculator. n
1
Instructions
2
Use black ink or black ball-point pen.
Fill in the boxes at the top of this page. 3
Answer all questions in Section A. 4
Answer one question from Section B. 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 7
the end of this book. Write the question number against your TOTAL
answer(s).
Show all your working.
Do all rough work in this book. Cross through any work you do
not want to be marked.
Information
The marks for the questions are shown in brackets.
The maximum mark for this paper is 78.
official
,official
, 2
Do not write
outside the
Section A box
Answer all questions in this section.
You are advised to spend no more than 1 hour and 15 minutes on
this section.
0 1 .1 Describe how stimulation of a Pacinian corpuscle produces a generator potential.
[3 marks]
Scientists investigated the stimulation of a Pacinian corpuscle in the skin of
a fingertip. The scientists applied two different pressures to the fingertip
and recorded the changes in membrane potential of the Pacinian
corpuscle’s sensory neurone.
Figure 1 shows the scientists’ results.
Figure 1
, 3
Do not write
outside the
0 1 .2 Use Figure 1 to describe what is meant by the all-or-nothing box
principle. [2
marks]
0 1 .3 On Figure 1, from 0.6 ms to 4.0 ms, no new generator potential could be produced.
What is this time period called?
[1 mark]
6
Turn over for the next question
Please write clearly in block capitals.
Centre Candidate
number number
Surname
Forename(s)
Candidate re
signatu
A-level
BIOLOGY
Paper 3
7402/3
Wednesday 21 June 2023 Morning Time allowed: 2 hours
Materials
For this paper you must have: For Examiner’s Use
a ruler with millimetre measurements
Questio Mark
a scientific calculator. n
1
Instructions
2
Use black ink or black ball-point pen.
Fill in the boxes at the top of this page. 3
Answer all questions in Section A. 4
Answer one question from Section B. 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 7
the end of this book. Write the question number against your TOTAL
answer(s).
Show all your working.
Do all rough work in this book. Cross through any work you do
not want to be marked.
Information
The marks for the questions are shown in brackets.
The maximum mark for this paper is 78.
official
,official
, 2
Do not write
outside the
Section A box
Answer all questions in this section.
You are advised to spend no more than 1 hour and 15 minutes on
this section.
0 1 .1 Describe how stimulation of a Pacinian corpuscle produces a generator potential.
[3 marks]
Scientists investigated the stimulation of a Pacinian corpuscle in the skin of
a fingertip. The scientists applied two different pressures to the fingertip
and recorded the changes in membrane potential of the Pacinian
corpuscle’s sensory neurone.
Figure 1 shows the scientists’ results.
Figure 1
, 3
Do not write
outside the
0 1 .2 Use Figure 1 to describe what is meant by the all-or-nothing box
principle. [2
marks]
0 1 .3 On Figure 1, from 0.6 ms to 4.0 ms, no new generator potential could be produced.
What is this time period called?
[1 mark]
6
Turn over for the next question
