Mark Scheme (Results)
2025 Predicted Paper
Pearson Edexcel Level 3 GCE
Edexcel AL Biology Marking Scheme 2A 2025 Predicted
PAPER 2 Advanced Level
1
, Edexcel AL Biology Marking Scheme 2A 2025 Predicted
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.
2
,Edexcel AL Biology Marking Scheme 2A 2025 Predicted
3
, Edexcel AL Biology Marking Scheme 2A 2025 Predicted
Comprehensive Marking Scheme
Question 1
(a):
(i) Which group represents the letters coloured in blue? [1]
Context and Justification:
• Context: This question tests knowledge of molecular structures in
biochemistry, specifically functional groups in glucose.
• Common Pattern: Multiple-choice questions on biomolecules frequently test
recognition of functional groups, bonds, or molecular arrangements.
• Approach: Identify the structure or group represented by the blue-colored
part of the glucose molecule.
• Theory to Learn: Understanding the structure of carbohydrates
(monosaccharides like glucose), including functional groups like hydroxyl (-
OH) and aldehyde.
• TLDR: Learn the key structural features of glucose.
Mark Scheme:
1. Correct Answer: C – Hydroxyl (-OH).
2. Marks: 1 mark for selecting the correct answer.
3. Explanation: Glucose is a hexose sugar with hydroxyl (-OH) groups attached
to each carbon except the one forming the aldehyde group. Blue regions
typically represent hydroxyl groups in diagrams.
(ii) Describe the role of glucose in aerobic respiration. [3]
Context and Justification:
• Context: This question examines the understanding of glucose metabolism in
cellular respiration.
• Common Pattern: Descriptive questions on glucose's role (2015–2023)
often require linking glucose to energy production pathways.
• Approach: Break the answer into glucose's role as a substrate, its
breakdown into ATP, and the production of intermediates.
• Theory to Learn: The steps of aerobic respiration—glycolysis, the Krebs
cycle, and oxidative phosphorylation.
• TLDR: Glucose is broken down to produce ATP during aerobic respiration.
4
2025 Predicted Paper
Pearson Edexcel Level 3 GCE
Edexcel AL Biology Marking Scheme 2A 2025 Predicted
PAPER 2 Advanced Level
1
, Edexcel AL Biology Marking Scheme 2A 2025 Predicted
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.
2
,Edexcel AL Biology Marking Scheme 2A 2025 Predicted
3
, Edexcel AL Biology Marking Scheme 2A 2025 Predicted
Comprehensive Marking Scheme
Question 1
(a):
(i) Which group represents the letters coloured in blue? [1]
Context and Justification:
• Context: This question tests knowledge of molecular structures in
biochemistry, specifically functional groups in glucose.
• Common Pattern: Multiple-choice questions on biomolecules frequently test
recognition of functional groups, bonds, or molecular arrangements.
• Approach: Identify the structure or group represented by the blue-colored
part of the glucose molecule.
• Theory to Learn: Understanding the structure of carbohydrates
(monosaccharides like glucose), including functional groups like hydroxyl (-
OH) and aldehyde.
• TLDR: Learn the key structural features of glucose.
Mark Scheme:
1. Correct Answer: C – Hydroxyl (-OH).
2. Marks: 1 mark for selecting the correct answer.
3. Explanation: Glucose is a hexose sugar with hydroxyl (-OH) groups attached
to each carbon except the one forming the aldehyde group. Blue regions
typically represent hydroxyl groups in diagrams.
(ii) Describe the role of glucose in aerobic respiration. [3]
Context and Justification:
• Context: This question examines the understanding of glucose metabolism in
cellular respiration.
• Common Pattern: Descriptive questions on glucose's role (2015–2023)
often require linking glucose to energy production pathways.
• Approach: Break the answer into glucose's role as a substrate, its
breakdown into ATP, and the production of intermediates.
• Theory to Learn: The steps of aerobic respiration—glycolysis, the Krebs
cycle, and oxidative phosphorylation.
• TLDR: Glucose is broken down to produce ATP during aerobic respiration.
4
