A LEVEL BIOLOGY A: Actual June 2025 MARK SCHEME PAPER 2: Biological
Diversity [OCR H420/02]
Exam Resource Summary
The A Level Biology A June 2025 Biological Diversity Mark Scheme (OCR H420/02) provides
the official, detailed marking guidance used by examiners to assess student performance on the
Biological Diversity paper. This document outlines the precise criteria for awarding marks,
including required scientific terminology, key points for full-credit explanations, data-analysis
expectations, and the structure of high-band responses across all question types. By clearly
defining acceptable answers, common misconceptions, and how marks are allocated, the mark
scheme enables students to understand examiner expectations and refine their exam technique.
This resource is an essential companion for targeted revision, helping learners evaluate their own
practice responses, strengthen biological reasoning, and build the accuracy and detail needed for
success in the May/June 2026 OCR A Level Biology A Biological Diversity examination.
Oxford Cambridge and RSA Examinations
,OCR (Oxford Cambridge and RSA) is a leading UK awarding body, providing a wide range of
qualifications to meet the needs of candidates of all ages and abilities. OCR qualifications
include AS/A Levels, Diplomas, GCSEs, Cambridge Nationals, Cambridge Technicals,
Functional Skills, Key Skills, Entry Level qualifications, NVQs and vocational qualifications in
areas such as IT, business, languages, teaching/training, administration and secretarial skills.
It is also responsible for developing new specifications to meet national requirements and the
needs of students and teachers. OCR is a not-for-profit organisation; any surplus made is
invested back into the establishment to help towards the development of qualifications and
support, which keep pace with the changing needs of today’s society.
This mark scheme is published as an aid to teachers and students, to indicate the requirements
of the examination. It shows the basis on which marks were awarded by examiners. It does not
indicate the details of the discussions which took place at an examiners’ meeting before marking
commenced.
All examiners are instructed that alternative correct answers and unexpected approaches in
candidates’ scripts must be given marks that fairly reflect the relevant knowledge and skills
demonstrated.
Mark schemes should be read in conjunction with the published question papers and the report
on the examination.
© OCR 2025
Oxford Cambridge and RSA Examinations
,H420/02 Mark Scheme June 2025
MARKING INSTRUCTIONS
PREPARATION FOR MARKING
RM ASSESSOR
1. Make sure that you have accessed and completed the relevant training packages for on-screen marking: RM Assessor Online Training: OCR
Essential Guide to Marking.
2. Make sure that you have read and understood the mark scheme and the question paper for this unit. These are available in RM Assessor
3. Log-in to RM Assessor and mark the required number of practice responses (“scripts”) and the required number of standardisation responses.
MARKING
1. Mark strictly to the mark scheme.
2. Marks awarded must relate directly to the marking criteria.
3. The schedule of dates is very important. It is essential that you meet the RM Assessor 50% and 100% (traditional 40% Batch 1 and 100% Batch 2)
deadlines. If you experience problems, you must contact your Team Leader (Supervisor) without delay.
4. If you are in any doubt about applying the mark scheme, consult your Team Leader by telephone, email or via the RM Assessor messaging system.
5. Crossed-Out Responses
Where a candidate has crossed out a response and provided a clear alternative then the crossed-out response is not marked. Where no alternative
response has been provided, examiners may give candidates the benefit of the doubt and mark the crossed-out response where legible.
Rubric Error Responses – Optional Questions
Where candidates have a choice of question across a whole paper or a whole section and have provided more answers than required, then all responses
are marked and the highest mark allowable within the rubric is given. Enter a mark for each question answered into RM Assessor, which will select the
highest mark from those awarded. (The underlying assumption is that the candidate has penalised themselves by attempting more questions than
necessary in the time allowed.)
2
, H420/02 Mark Scheme June 2025
Multiple-Choice Question Responses
When a multiple-choice question has only a single, correct response and a candidate provides two responses (even if one of these responses is correct),
then no mark should be awarded (as it is not possible to determine which was the first response selected by the candidate).
When a question requires candidates to select more than one option/multiple options, then local marking arrangements need to ensure consistency of
approach.
Contradictory Responses
When a candidate provides contradictory responses, then no mark should be awarded, even if one of the answers is correct.
Short Answer Questions (requiring only a list by way of a response, usually worth only one mark per response)
Where candidates are required to provide a set number of short answer responses then only the set number of responses should be marked. The
response space should be marked from left to right on each line and then line by line until the required number of responses have been considered. The
remaining responses should not then be marked. Examiners will have to apply judgement as to whether a ‘second response’ on a line is a development
of the ‘first response’, rather than a separate, discrete response. (The underlying assumption is that the candidate is attempting to hedge their bets
and therefore getting undue benefit rather than engaging with the question and giving the most relevant/correct responses.)
Short Answer Questions (requiring a more developed response, worth two or more marks)
If the candidates are required to provide a description of, say, three items or factors and four items or factors are provided, then mark on a similar basis
– that is downwards (as it is unlikely in this situation that a candidate will provide more than one response in each section of the response space).
Longer Answer Questions (requiring a developed response)
Where candidates have provided two (or more) responses to a medium or high tariff question which only required a single (developed) response and
not crossed out the first response, then only the first response should be marked. Examiners will need to apply professional judgement as to whether
the second (or a subsequent) response is a ‘new start’ or simply a poorly expressed continuation of the first response.
6. Always check the pages (and additional objects if present) at the end of the response in case any answers have been continued there. If the candidate
has continued an answer there, then add the annotation ‘SEEN’ to confirm that the work has been seen and mark any responses using the annotations
in section 11.
3
Diversity [OCR H420/02]
Exam Resource Summary
The A Level Biology A June 2025 Biological Diversity Mark Scheme (OCR H420/02) provides
the official, detailed marking guidance used by examiners to assess student performance on the
Biological Diversity paper. This document outlines the precise criteria for awarding marks,
including required scientific terminology, key points for full-credit explanations, data-analysis
expectations, and the structure of high-band responses across all question types. By clearly
defining acceptable answers, common misconceptions, and how marks are allocated, the mark
scheme enables students to understand examiner expectations and refine their exam technique.
This resource is an essential companion for targeted revision, helping learners evaluate their own
practice responses, strengthen biological reasoning, and build the accuracy and detail needed for
success in the May/June 2026 OCR A Level Biology A Biological Diversity examination.
Oxford Cambridge and RSA Examinations
,OCR (Oxford Cambridge and RSA) is a leading UK awarding body, providing a wide range of
qualifications to meet the needs of candidates of all ages and abilities. OCR qualifications
include AS/A Levels, Diplomas, GCSEs, Cambridge Nationals, Cambridge Technicals,
Functional Skills, Key Skills, Entry Level qualifications, NVQs and vocational qualifications in
areas such as IT, business, languages, teaching/training, administration and secretarial skills.
It is also responsible for developing new specifications to meet national requirements and the
needs of students and teachers. OCR is a not-for-profit organisation; any surplus made is
invested back into the establishment to help towards the development of qualifications and
support, which keep pace with the changing needs of today’s society.
This mark scheme is published as an aid to teachers and students, to indicate the requirements
of the examination. It shows the basis on which marks were awarded by examiners. It does not
indicate the details of the discussions which took place at an examiners’ meeting before marking
commenced.
All examiners are instructed that alternative correct answers and unexpected approaches in
candidates’ scripts must be given marks that fairly reflect the relevant knowledge and skills
demonstrated.
Mark schemes should be read in conjunction with the published question papers and the report
on the examination.
© OCR 2025
Oxford Cambridge and RSA Examinations
,H420/02 Mark Scheme June 2025
MARKING INSTRUCTIONS
PREPARATION FOR MARKING
RM ASSESSOR
1. Make sure that you have accessed and completed the relevant training packages for on-screen marking: RM Assessor Online Training: OCR
Essential Guide to Marking.
2. Make sure that you have read and understood the mark scheme and the question paper for this unit. These are available in RM Assessor
3. Log-in to RM Assessor and mark the required number of practice responses (“scripts”) and the required number of standardisation responses.
MARKING
1. Mark strictly to the mark scheme.
2. Marks awarded must relate directly to the marking criteria.
3. The schedule of dates is very important. It is essential that you meet the RM Assessor 50% and 100% (traditional 40% Batch 1 and 100% Batch 2)
deadlines. If you experience problems, you must contact your Team Leader (Supervisor) without delay.
4. If you are in any doubt about applying the mark scheme, consult your Team Leader by telephone, email or via the RM Assessor messaging system.
5. Crossed-Out Responses
Where a candidate has crossed out a response and provided a clear alternative then the crossed-out response is not marked. Where no alternative
response has been provided, examiners may give candidates the benefit of the doubt and mark the crossed-out response where legible.
Rubric Error Responses – Optional Questions
Where candidates have a choice of question across a whole paper or a whole section and have provided more answers than required, then all responses
are marked and the highest mark allowable within the rubric is given. Enter a mark for each question answered into RM Assessor, which will select the
highest mark from those awarded. (The underlying assumption is that the candidate has penalised themselves by attempting more questions than
necessary in the time allowed.)
2
, H420/02 Mark Scheme June 2025
Multiple-Choice Question Responses
When a multiple-choice question has only a single, correct response and a candidate provides two responses (even if one of these responses is correct),
then no mark should be awarded (as it is not possible to determine which was the first response selected by the candidate).
When a question requires candidates to select more than one option/multiple options, then local marking arrangements need to ensure consistency of
approach.
Contradictory Responses
When a candidate provides contradictory responses, then no mark should be awarded, even if one of the answers is correct.
Short Answer Questions (requiring only a list by way of a response, usually worth only one mark per response)
Where candidates are required to provide a set number of short answer responses then only the set number of responses should be marked. The
response space should be marked from left to right on each line and then line by line until the required number of responses have been considered. The
remaining responses should not then be marked. Examiners will have to apply judgement as to whether a ‘second response’ on a line is a development
of the ‘first response’, rather than a separate, discrete response. (The underlying assumption is that the candidate is attempting to hedge their bets
and therefore getting undue benefit rather than engaging with the question and giving the most relevant/correct responses.)
Short Answer Questions (requiring a more developed response, worth two or more marks)
If the candidates are required to provide a description of, say, three items or factors and four items or factors are provided, then mark on a similar basis
– that is downwards (as it is unlikely in this situation that a candidate will provide more than one response in each section of the response space).
Longer Answer Questions (requiring a developed response)
Where candidates have provided two (or more) responses to a medium or high tariff question which only required a single (developed) response and
not crossed out the first response, then only the first response should be marked. Examiners will need to apply professional judgement as to whether
the second (or a subsequent) response is a ‘new start’ or simply a poorly expressed continuation of the first response.
6. Always check the pages (and additional objects if present) at the end of the response in case any answers have been continued there. If the candidate
has continued an answer there, then add the annotation ‘SEEN’ to confirm that the work has been seen and mark any responses using the annotations
in section 11.
3
