Friday 12 June 2026 – Morning
A Level Biology A
H420/02 Biological diversity
Time allowed: 2 hours 15 minutes
You can use:
GCE
*
• a scientific or graphical calculator
• a ruler (cm/mm)
Biology A
H420/02: Biological diversity
* H 4 2 0 0 2 *
*
Please write clearly in black ink. Do not write in the barcodes. A Level
Centre number Candidate number
Mark Scheme for June 2026
First name(s)
Last name
INSTRUCTIONS
• Use black ink. You can use an HB pencil, but only for graphs and diagrams.
• Write your answer to each question in the space provided. If you need extra space use
the lined page at the end of this booklet. The question numbers must be clearly shown.
• Answer all the questions.
• Where appropriate, your answer should be supported with working. Marks might be
given for using a correct method, even if your answer is wrong.
INFORMATION
• The total mark for this paper is 100.
• The marks for each question are shown in brackets [ ].
• Quality of extended response will be assessed in questions marked with an asterisk (*).
• This document has 28 pages.
ADVICE
• Read each question carefully before you start your answer.
Cambridge 2026 [601/4260/1] Cambridge is an exempt Charity
DC (SL/TC) 359141/5 Turn over
Cambridge
, 2
Section A
You should spend a maximum of 20 minutes on this section.
Cambridge is a leading UK awarding body, providing a wide range of qualifications to
Write your answer to each question in the box provided.
meet the needs of candidates of all ages and abilities. Cambridge qualifications include
AS/A Levels, Diplomas, GCSEs, Cambridge Nationals, Cambridge Technicals, Functional Skills,
1 Which class of biomolecules does this molecule belong to? Key Skills, Entry Level qualifications, NVQs and vocational qualifications in areas such as IT,
business, languages, teaching/training, administration and secretarial skills.
H
H O
It is also responsible for developing new specifications to meet national requirements and the
needs of students and teachers. Cambridge is a not-for-profit organisation; any surplus
N C C
made is invested back into the establishment to help towards the development of qualifications
H O H and support, which keep pace with the changing needs of today’s society.
H
This mark scheme is published as an aid to teachers and students, to indicate the requirements
A Amino acids 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
B Monosaccharides commenced.
C Nucleic acids 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
D Purines demonstrated.
Mark schemes should be read in conjunction with the published question papers and the report
Your answer [1]
on the examination.
2 Which bond forms a polymer from monomers by a condensation reaction?
Cambridge 2026
A Disulfide bond between two cysteines in a polypeptide
B Ester bond between a glycerol and a fatty acid
C Hydrogen bond between two water molecules
D Peptide bond between two adjacent amino acids in a polypeptide
Your answer [1]
Cambridge 2026
Cambridge
, H420/02 Mark Scheme June 2026
3
3 This is a diagram of an α-glucose molecule. Marking Instructions
Preparation For Marking
CH2OH 1. RM Assessor
O • Access and complete the on-screen marking training packages: Examiner Training (RMA3).
H H
H
• Read the mark scheme and question paper for this component or unit.
OH H
OH OH • The mark scheme and question paper are available in RM Assessor or on your Component Page if you use the Training Platform for standardisation.
• Log in to RM Assessor and mark the required number of practice scripts and the required number of standardisation scripts.
H OH
Marking
Which of the following parts of the molecule allow(s) α-glucose to form the glycosidic bonds in a
glycogen molecule? 2. General Guidance
1. H • Mark strictly to the mark scheme.
H
H
• Marks awarded must relate directly to the marking criteria.
OH
OH
OH • If you are in any doubt about applying the mark scheme, consult your Team Leader by phone, email or via the RM Assessor messaging system.
CH
CH OH
2. CH222OH
OH
• It is essential that you meet the RM Assessor 50% and 100% batch deadlines. For traditional marking this will be 40% and 100%. If you experience
problems, contact your Team Leader without delay.
H
H
H • 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
H
H 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
3. H
in Section 6.
OH • The RM Assessor comments box is used by your Team Leader to explain the marking of the practice responses. Use these comments when checking
OH
OH your practice responses. Do not use the comments box for any other reason.
A 1, 2 and 3 • Before the end of the marking period send a brief report on the performance of candidates to your Team Leader via email. The report should contain
notes on strengths displayed as well as common errors or weaknesses. Constructive criticism of the question paper/mark scheme is also appreciated.
B Only 1 and 2
2
C Only 2 and 3
D Only 1
Your answer [1]
Cambridge 2026 Turn over
, H420/02 Mark Scheme June 2026
4
4 Which option describes a property of an α-glucose molecule?
3. No Response and Crossed-out Answers
A α-glucose is energy dense so able to function as an energy storage molecule.
Using the No Response (NR) option. Only mark as NR if:
B α-glucose monomers can polymerise to form cellulose molecules.
- the answer space is blank
C OH and H allow glucose to form hydrogen bonds with water.
- there is only a comment not related to the question (e.g., ‘can’t do’, ‘don’t know’)
D OH and H mean glucose is polar and so cannot cross membranes by diffusion.
- there is only a mark (e.g., a dash, a question mark) which is not an attempt at the question.
Your answer [1] Note: Enter 0 marks for an attempt that earns no credit (including copying out the question). Do not use NR.
Crossed-out answers
5 Which option is an insoluble protein?
If a candidate has crossed out an answer and written a clear alternative, do not mark the crossed-out answer.
A Amylase
If a candidate has crossed out an answer and not written a clear alternative, mark the crossed-out answer if it is readable.
B Amylose
4. Responses with more answers than needed
C Elastin
D Haemoglobin • Multiple-choice question answers
When a multiple-choice question has only one correct answer and a candidate has written two or more answers (even if one of these answers is
correct), do not award a mark.
Your answer [1]
When a multiple-choice question asks candidates to select more than one option the marking guidance from your Principal Examiner will ensure
6 Wing length in fruit flies is controlled by a single gene with two alleles. The allele for consistency of approach.
long wings, T, is dominant. The allele for short wings, t, is recessive.
Contradictory answers in points-based questions
Flies with the genotype T T have long wings. Do not award any marks, even if one of the answers is correct.
Flies with the genotype t t have short wings.
• Rubric error answers – optional questions
A fly with genotype T t is crossed with a fly with genotype t t. Where candidates have a choice of question/s and they provide more answers than required, all responses are marked and entered into RM Assessor.
The highest mark allowable within the rubric will automatically be selected.
What is the expected offspring phenotype ratio for this cross?
3
A All long-winged
B 1 long-winged : 1 short-winged
C 3 long-winged : 1 short-winged
D 4 long-winged : 1 short-winged
Your answer [1]
Cambridge 2026
A Level Biology A
H420/02 Biological diversity
Time allowed: 2 hours 15 minutes
You can use:
GCE
*
• a scientific or graphical calculator
• a ruler (cm/mm)
Biology A
H420/02: Biological diversity
* H 4 2 0 0 2 *
*
Please write clearly in black ink. Do not write in the barcodes. A Level
Centre number Candidate number
Mark Scheme for June 2026
First name(s)
Last name
INSTRUCTIONS
• Use black ink. You can use an HB pencil, but only for graphs and diagrams.
• Write your answer to each question in the space provided. If you need extra space use
the lined page at the end of this booklet. The question numbers must be clearly shown.
• Answer all the questions.
• Where appropriate, your answer should be supported with working. Marks might be
given for using a correct method, even if your answer is wrong.
INFORMATION
• The total mark for this paper is 100.
• The marks for each question are shown in brackets [ ].
• Quality of extended response will be assessed in questions marked with an asterisk (*).
• This document has 28 pages.
ADVICE
• Read each question carefully before you start your answer.
Cambridge 2026 [601/4260/1] Cambridge is an exempt Charity
DC (SL/TC) 359141/5 Turn over
Cambridge
, 2
Section A
You should spend a maximum of 20 minutes on this section.
Cambridge is a leading UK awarding body, providing a wide range of qualifications to
Write your answer to each question in the box provided.
meet the needs of candidates of all ages and abilities. Cambridge qualifications include
AS/A Levels, Diplomas, GCSEs, Cambridge Nationals, Cambridge Technicals, Functional Skills,
1 Which class of biomolecules does this molecule belong to? Key Skills, Entry Level qualifications, NVQs and vocational qualifications in areas such as IT,
business, languages, teaching/training, administration and secretarial skills.
H
H O
It is also responsible for developing new specifications to meet national requirements and the
needs of students and teachers. Cambridge is a not-for-profit organisation; any surplus
N C C
made is invested back into the establishment to help towards the development of qualifications
H O H and support, which keep pace with the changing needs of today’s society.
H
This mark scheme is published as an aid to teachers and students, to indicate the requirements
A Amino acids 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
B Monosaccharides commenced.
C Nucleic acids 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
D Purines demonstrated.
Mark schemes should be read in conjunction with the published question papers and the report
Your answer [1]
on the examination.
2 Which bond forms a polymer from monomers by a condensation reaction?
Cambridge 2026
A Disulfide bond between two cysteines in a polypeptide
B Ester bond between a glycerol and a fatty acid
C Hydrogen bond between two water molecules
D Peptide bond between two adjacent amino acids in a polypeptide
Your answer [1]
Cambridge 2026
Cambridge
, H420/02 Mark Scheme June 2026
3
3 This is a diagram of an α-glucose molecule. Marking Instructions
Preparation For Marking
CH2OH 1. RM Assessor
O • Access and complete the on-screen marking training packages: Examiner Training (RMA3).
H H
H
• Read the mark scheme and question paper for this component or unit.
OH H
OH OH • The mark scheme and question paper are available in RM Assessor or on your Component Page if you use the Training Platform for standardisation.
• Log in to RM Assessor and mark the required number of practice scripts and the required number of standardisation scripts.
H OH
Marking
Which of the following parts of the molecule allow(s) α-glucose to form the glycosidic bonds in a
glycogen molecule? 2. General Guidance
1. H • Mark strictly to the mark scheme.
H
H
• Marks awarded must relate directly to the marking criteria.
OH
OH
OH • If you are in any doubt about applying the mark scheme, consult your Team Leader by phone, email or via the RM Assessor messaging system.
CH
CH OH
2. CH222OH
OH
• It is essential that you meet the RM Assessor 50% and 100% batch deadlines. For traditional marking this will be 40% and 100%. If you experience
problems, contact your Team Leader without delay.
H
H
H • 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
H
H 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
3. H
in Section 6.
OH • The RM Assessor comments box is used by your Team Leader to explain the marking of the practice responses. Use these comments when checking
OH
OH your practice responses. Do not use the comments box for any other reason.
A 1, 2 and 3 • Before the end of the marking period send a brief report on the performance of candidates to your Team Leader via email. The report should contain
notes on strengths displayed as well as common errors or weaknesses. Constructive criticism of the question paper/mark scheme is also appreciated.
B Only 1 and 2
2
C Only 2 and 3
D Only 1
Your answer [1]
Cambridge 2026 Turn over
, H420/02 Mark Scheme June 2026
4
4 Which option describes a property of an α-glucose molecule?
3. No Response and Crossed-out Answers
A α-glucose is energy dense so able to function as an energy storage molecule.
Using the No Response (NR) option. Only mark as NR if:
B α-glucose monomers can polymerise to form cellulose molecules.
- the answer space is blank
C OH and H allow glucose to form hydrogen bonds with water.
- there is only a comment not related to the question (e.g., ‘can’t do’, ‘don’t know’)
D OH and H mean glucose is polar and so cannot cross membranes by diffusion.
- there is only a mark (e.g., a dash, a question mark) which is not an attempt at the question.
Your answer [1] Note: Enter 0 marks for an attempt that earns no credit (including copying out the question). Do not use NR.
Crossed-out answers
5 Which option is an insoluble protein?
If a candidate has crossed out an answer and written a clear alternative, do not mark the crossed-out answer.
A Amylase
If a candidate has crossed out an answer and not written a clear alternative, mark the crossed-out answer if it is readable.
B Amylose
4. Responses with more answers than needed
C Elastin
D Haemoglobin • Multiple-choice question answers
When a multiple-choice question has only one correct answer and a candidate has written two or more answers (even if one of these answers is
correct), do not award a mark.
Your answer [1]
When a multiple-choice question asks candidates to select more than one option the marking guidance from your Principal Examiner will ensure
6 Wing length in fruit flies is controlled by a single gene with two alleles. The allele for consistency of approach.
long wings, T, is dominant. The allele for short wings, t, is recessive.
Contradictory answers in points-based questions
Flies with the genotype T T have long wings. Do not award any marks, even if one of the answers is correct.
Flies with the genotype t t have short wings.
• Rubric error answers – optional questions
A fly with genotype T t is crossed with a fly with genotype t t. Where candidates have a choice of question/s and they provide more answers than required, all responses are marked and entered into RM Assessor.
The highest mark allowable within the rubric will automatically be selected.
What is the expected offspring phenotype ratio for this cross?
3
A All long-winged
B 1 long-winged : 1 short-winged
C 3 long-winged : 1 short-winged
D 4 long-winged : 1 short-winged
Your answer [1]
Cambridge 2026
