Pearson
Edexcel
Mark Scheme (Results)
Summer 2025
Pearson Edexcel A Level GCE
In Biology A Salters – Nuffield (9BN0)
Paper 01: The Natural Environment
and Species Survive
,Summer 2025
,General Marking Guidance
All candidates must receive the same treatment. Examiners must mark
the first candidate in exactly the same way as they mark the last.
Mark schemes should be applied positively. Candidates must be rewarded
for what they have shown they can do rather than penalised for
omissions.
Examiners should mark according to the mark scheme not according to
their perception of where the grade boundaries may lie.
There is no ceiling on achievement. All marks on the mark scheme should
be used appropriately.
All the marks on the mark scheme are designed to be awarded. Examiners
should always award full marks if deserved, i.e. if the answer matches the
mark scheme. Examiners should also be prepared to award zero marks if
the candidate’s response is not worthy of credit according to the mark
scheme.
Where some judgement is required, mark schemes will provide the
principles by which marks will be awarded and exemplification may be
limited.
When examiners are in doubt regarding the application of the mark
scheme to a candidate’s response, the team leader must be consulted.
Crossed out work should be marked UNLESS the candidate has replaced it
with an alternative response.
, Question Answer Additional guidance Mark
Number
description that makes reference to the following: IGNORE any explanations
fall in (body) temperature (1) ALLOW algor mortis / cooling ALLOW
increase in temperature if
qualified
DO NOT ALLOW ‘increase or decrease’
without giving reason for
possible increase
rigor mortis (1) ALLOW stiffening of the muscles
IGNORE contraction of the muscles
ALLOW description of autolysis as
autolysis / bloating / fall in pH / break down of the body by its
discolouration of skin (1) own enzymes
ALLOW livor mortis / hypostasis
blood pooling
ALLOW ref to a named colour for
discoloration
Question Answer Mark
Number
Edexcel
Mark Scheme (Results)
Summer 2025
Pearson Edexcel A Level GCE
In Biology A Salters – Nuffield (9BN0)
Paper 01: The Natural Environment
and Species Survive
,Summer 2025
,General Marking Guidance
All candidates must receive the same treatment. Examiners must mark
the first candidate in exactly the same way as they mark the last.
Mark schemes should be applied positively. Candidates must be rewarded
for what they have shown they can do rather than penalised for
omissions.
Examiners should mark according to the mark scheme not according to
their perception of where the grade boundaries may lie.
There is no ceiling on achievement. All marks on the mark scheme should
be used appropriately.
All the marks on the mark scheme are designed to be awarded. Examiners
should always award full marks if deserved, i.e. if the answer matches the
mark scheme. Examiners should also be prepared to award zero marks if
the candidate’s response is not worthy of credit according to the mark
scheme.
Where some judgement is required, mark schemes will provide the
principles by which marks will be awarded and exemplification may be
limited.
When examiners are in doubt regarding the application of the mark
scheme to a candidate’s response, the team leader must be consulted.
Crossed out work should be marked UNLESS the candidate has replaced it
with an alternative response.
, Question Answer Additional guidance Mark
Number
description that makes reference to the following: IGNORE any explanations
fall in (body) temperature (1) ALLOW algor mortis / cooling ALLOW
increase in temperature if
qualified
DO NOT ALLOW ‘increase or decrease’
without giving reason for
possible increase
rigor mortis (1) ALLOW stiffening of the muscles
IGNORE contraction of the muscles
ALLOW description of autolysis as
autolysis / bloating / fall in pH / break down of the body by its
discolouration of skin (1) own enzymes
ALLOW livor mortis / hypostasis
blood pooling
ALLOW ref to a named colour for
discoloration
Question Answer Mark
Number
