Cambridge International AS & A Level Biology (9700) Past Papers: Grade Thresholds and Examiner Report Notes

This page is a guide to the past papers for Cambridge International AS & A Level Biology (9700). It covers twelve series, from March 2021 to November 2024. The grade thresholds are copied from Cambridge’s official grade-threshold documents, and the examiner notes are our own summaries of Cambridge’s Principal Examiner Reports for Teachers. We do not host any papers: every paper, mark scheme and report is on Cambridge’s own site.

Where to get the official papers

• Cambridge International AS & A Level Biology (9700) syllabus page
• 9700 past papers, mark schemes, examiner reports and grade thresholds

Cambridge publishes recent papers, mark schemes, examiner reports and grade thresholds on the syllabus’s past-papers page; older series are available to schools through the School Support Hub.

Use the three documents together. Sit the paper first, under timed conditions. Then mark it strictly with the mark scheme, which shows the points that earn credit. Last, read the examiner report for that series. It tells you where candidates lost marks and why, which is often where you lost them too.

The current syllabus is for examination in 2025, 2026 and 2027. The papers on this page (2021 to 2024) were set on earlier versions of the syllabus. Check the syllabus version on the paper’s front cover against the current syllabus before you rely on an old question. The topic names used on this page are the current syllabus’s.

Series index

Components use Cambridge’s numbering: Paper 1 Multiple Choice, Paper 2 AS Level Structured Questions, Paper 3 Advanced Practical Skills, Paper 4 A Level Structured Questions, Paper 5 Planning, Analysis and Evaluation. The second digit is the variant.

Series	Papers (components) examined	Examiner report notes	Grade thresholds
November 2025	Not summarised here	Not summarised here	Cambridge past-papers page
June 2025	Not summarised here	Not summarised here	Cambridge past-papers page
March 2025	Not summarised here	Not summarised here	Cambridge past-papers page
November 2024	11, 12, 13, 21, 22, 23, 31, 33, 34, 35, 36, 41, 42, 43, 51, 52, 53	Summarised below	A Level and AS
June 2024	11, 12, 13, 21, 22, 23, 31, 32, 33, 34, 35, 41, 42, 43, 51, 52, 53	Summarised below	A Level and AS
March 2024	12, 22, 33, 42, 52	Summarised below	A Level and AS
November 2023	11, 12, 13, 21, 22, 23, 31, 33, 34, 35, 36, 41, 42, 43, 51, 52, 53	Summarised below	A Level and AS
June 2023	11, 12, 13, 21, 22, 23, 31, 32, 33, 34, 35, 41, 42, 43, 51, 52, 53	Summarised below	A Level and AS
March 2023	12, 22, 33, 42, 52	Summarised below	A Level and AS
November 2022	11, 12, 13, 21, 22, 23, 31, 33, 34, 35, 36, 41, 42, 43, 51, 52, 53	Summarised below	A Level and AS
June 2022	11, 12, 13, 21, 22, 23, 31, 32, 33, 34, 35, 41, 42, 43, 51, 52, 53	Summarised below	A Level and AS
March 2022	12, 22, 33, 42, 52	Summarised below	AS only
November 2021	11, 12, 13, 21, 22, 23, 31, 33, 34, 35, 36, 41, 42, 43, 51, 52, 53	Summarised below	A Level and AS
June 2021	11, 12, 13, 21, 22, 23, 31, 32, 33, 34, 35, 41, 42, 43, 51, 52, 53	Summarised below	A Level and AS
March 2021	12, 22, 33, 42, 52	Summarised below	A Level and AS
November 2020	Not summarised here	Not summarised here	Cambridge past-papers page
June 2020	Not summarised here (Cambridge cancelled this series because of COVID-19)	Not summarised here	Cambridge past-papers page
March 2020	Not summarised here	Not summarised here	Cambridge past-papers page
November 2019	Not summarised here	Not summarised here	Cambridge past-papers page
June 2019	Not summarised here	Not summarised here	Cambridge past-papers page
March 2019	Not summarised here	Not summarised here	Cambridge past-papers page

What examiners keep saying

These errors turn up again and again across the twelve reports. They are grouped by the syllabus topic they belong to.

• Cell structure. Magnification slips (answers out by a factor of ten, magnification confused with resolution, or thought to change the real size), organelles or micrograph types misidentified, and forgetting that mitochondria and chloroplasts carry their own circular DNA and 70S ribosomes. March 2021, June 2021, November 2022, March 2023, June 2023, November 2023, June 2024, November 2024.
• Biological molecules. Hydrogen bonds called strong, peptide or covalent bonds placed in the wrong level of protein structure, water put on the wrong side of condensation and hydrolysis, and a collagen molecule confused with a collagen fibre. March 2021, June 2021, March 2022, November 2022, March 2023, June 2023, June 2024, November 2024.
• Enzymes. Km mixed up with Vmax, and rate curves described instead of explained through active sites and enzyme-substrate complexes. Plateaus are often blamed on denaturation or on the substrate running out, when the substrate has become limiting. June 2021, March 2022, November 2022, June 2023, November 2023, March 2024, June 2024, November 2024.
• Cell membranes and transport. Facilitated diffusion given an ATP requirement, carrier proteins limited to active transport, and ions or glucose said to be blocked by size instead of by charge or polarity. Water movement must be explained in water-potential terms, not water concentration or tonicity. June 2021, November 2021, June 2022, November 2022, June 2023, November 2023, March 2024, June 2024.
• The mitotic cell cycle. Centromere confused with centrosome, and chromatid, chromosome and chromatin used as if they meant the same thing, especially when counting at anaphase. June 2021, March 2022, June 2022, June 2023, November 2023, June 2024.
• Nucleic acids and protein synthesis. Thymine written into RNA or uracil into DNA, “base” written for nucleotide, replication confused with transcription, and the primary transcript called mRNA or splicing called a mutation. November 2021, March 2022, June 2022, March 2023, June 2023, March 2024, June 2024, November 2024.
• Transport in plants. Cohesion and adhesion swapped, sieve tubes given nuclei or lignin, and osmosis used for water moving where no membrane is crossed. June 2021, November 2021, March 2022, March 2023, June 2023, November 2023, November 2024.
• Transport in mammals. Carboxyhaemoglobin written for carbaminohaemoglobin, red blood cells treated as the molecule that binds gases, and dissociation curves moved up or down instead of sideways. November 2021, November 2023, March 2024.
• Infectious diseases and Immunity. Antibody confused with antibiotic, the vector or the disease named as the pathogen, T cells said to secrete antibodies, antibodies treated as cells or as memory, and active and passive immunity swapped. June 2021, November 2021, November 2022, March 2023, June 2023, November 2023, March 2024, June 2024.
• Energy and respiration. ATPase written for ATP synthase, ATP synthase said to pump protons, NAD said to carry protons rather than hydrogen, energy said to be “produced”, and coenzymes called enzymes. March 2021, June 2021, March 2022, June 2022, November 2022, March 2023, June 2023, June 2024.
• Homeostasis. Ultrafiltration described as diffusion, the direction of ADH secretion reversed or ADH said to be made rather than secreted, and the reabsorption process described when the question asked how the cells are adapted for it. November 2021, June 2022, March 2023, June 2023, November 2023, March 2024, November 2024.
• Control and coordination. The neurone rather than its membrane said to depolarise, voltage-gated channels confused with ligand-gated channels or with the sodium-potassium pump, and ATP linked to depolarisation instead of restoring the resting potential. June 2021, November 2021, March 2022, June 2022, June 2024.
• Inheritance. Genes and alleles used as if they were the same, genetic diagrams with no key, genotypes or phenotypes, Hardy-Weinberg slips (2pq halved or written as pq, q not square-rooted, rounding too early) and chi-squared conclusions reversed. June 2021, November 2021, March 2022, November 2022, June 2023, November 2023, March 2024, June 2024, November 2024.
• Selection and evolution; Genetic technology. Genetic drift treated as a form of natural selection, alleles rather than organisms said to survive, and mutations said to be caused by the environment or by selection. In gene technology, mRNA is “converted” into cDNA instead of acting as a template, and gene therapy is confused with genetic engineering. March 2021, June 2021, November 2021, June 2022, November 2022, June 2023, June 2024, November 2024.
• Practical skills (Papers 3 and 5). Non-linear or badly chosen y-axis scales, drawing lines that do not meet, serial dilution used where proportional dilution was needed, “average” for mean, a control confused with a controlled variable, null hypotheses about difference and correlation swapped, and error bars treated as proof of significance. Every series from March 2021 to November 2024.

Exam technique the reports repeat:

• Obey the command word. Describe means the trend plus a data quote; explain means the biology behind it. Where a question says describe and explain, do both. Every series from March 2021 to November 2024.
• Quote data with units. Give paired values from the figure, read graphs carefully, and work out rates from gradients, not single readings. June 2021, June 2022, March 2024, June 2024, November 2024.
• Make comparisons two-sided. Mention both items in each statement, one feature at a time; include similarities if asked. A table helps. March 2021, June 2021, June 2023, March 2024, June 2024.
• Write the full term first. Use only syllabus abbreviations, and spell terms exactly, because a misspelling can change the meaning. November 2022, June 2023, June 2024, November 2024.
• Read everything before you write. Annotate the stem, use every named figure, and check each part has been answered, including labels and graph lines with no answer lines. March 2023, June 2023, November 2023, November 2024.
• Give only the number of answers asked for. Extra answers are not marked, and contradictions cost the mark. June 2021, November 2022, June 2023.

November 2024

The AS papers drew on cell structure, biological molecules, the Bohr shift, mitosis, DNA replication, gas exchange tissues and immunity, including monoclonal antibodies and T-lymphocytes. Paper 4 put its weight on nerve impulses, stomata, respiration, the kidney, the Calvin cycle, inheritance, gene technology and statistics. The Paper 11 report names nucleic acids and protein synthesis as a weak area, and the Papers 41 and 43 report found inheritance and molecular genetics harder. Good scripts read the stem and figures first, chose exact terms and did what the command word asked. Weaker ones described instead of explaining, gave general accounts that ignored the context, and missed items that had no answer lines.

Where marks were lost:

• Paper 21: items without answer lines skipped; a plateau blamed on the substrate running out rather than becoming limiting.
• Paper 22: osmosis used for water on the apoplast route, where no membrane is crossed; enzyme optima applied to haemoglobin; telomeres called genes.
• Paper 23: “base” for nucleotide; a general replication account instead of the stage shown; endocytosis and exocytosis swapped; microvilli called cilia.
• Papers 41 and 43: similarities given when asked to contrast; filtrate called blood; urea said to form in the kidney; gametes shown as diploid.
• Paper 42: standard deviations not squared in the t-test; conclusions not framed around the means; plasmids named as gene therapy vectors.
• Papers 31, 33, 34, 35 and 36: weak y-axis scales and unmeasured scale bars; in Paper 34, serial dilution used where proportional dilution was needed.

Grade thresholds – November 2024

Full A Level, all papers in this series

Option	Components	Max	A*	A	B	C	D	E
AX	11, 21, 31, 41, 51	260	198	175	152	131	110	90
AY	12, 22, 33, 42, 52	260	192	171	150	128	106	85
AZ	13, 23, 35, 43, 53	260	195	171	147	125	103	81
HY	12, 22, 34, 42, 52	260	192	171	150	128	107	86
HZ	13, 23, 36, 43, 53	260	197	174	151	128	106	84

AS Level only

Option	Components	Max	a	b	c	d	e
S1	11, 21, 31	130	91	80	70	60	50
S3	12, 22, 33	130	92	81	70	59	49
S4	12, 22, 34	130	92	81	70	60	50
S5	13, 23, 35	130	87	75	63	52	41
S6	13, 23, 36	130	90	79	67	55	44

Not shown: 13 further route(s) in the official table (staged entries that carry AS marks from an earlier series, or other special routes). See the official document.

Official documents: past papers, mark schemes and examiner report

June 2024

Questions ranged across membranes, protein structure, enzyme kinetics, transport in mammals and plants, immunity, RNA splicing, respiration, photosynthesis, inheritance, gene control, nerves and genetic technology. The report credits scripts that blended the information given with their own knowledge, chose precise terms and made each comparison clearly two-sided. Weaker scripts described data when asked to explain or deduce, made up their own abbreviations, leaned on vague words such as “amount”, wrote gene where they meant allele, carried prokaryote operon ideas over to eukaryotes, and reproduced remembered mark-scheme points that did not answer the question on the paper.

Where marks were lost:

• Papers 11 to 13: Km confused with Vmax; hydrogen bonds in proteins treated as strong; the template strand confused with the non-transcribed strand.
• Papers 21 and 22: splicing called a mutation; antibodies treated as memory; vaccines confused with vaccination programmes; abbreviations used before the full term.
• Paper 23: resolution confused with magnification; purines thought to have a single ring.
• Papers 41 to 43: a gene said to be “not coded” instead of giving a non-functional product; neurones rather than membranes said to depolarise; energy “produced”; epistasis missed; weak recall of the enzymes and promoters used in gene technology.
• Papers 31 to 35: in Paper 31, osmosis theory recited instead of explaining the candidate’s own results through water potential; in Paper 33, bar charts with touching bars; in Paper 32, serial dilution where proportional dilution was needed.
• Papers 51 to 53: “amount” and “average”; null hypotheses written as correlations; a control confused with standardised variables; the wrong critical value.

Grade thresholds – June 2024

Full A Level, all papers in this series

Option	Components	Max	A*	A	B	C	D	E
AX	11, 21, 31, 41, 51	260	207	186	165	143	122	101
AY	12, 22, 33, 42, 52	260	187	162	137	116	96	76
AZ	13, 23, 35, 43, 53	260	201	180	159	137	116	95
HX	11, 21, 32, 41, 51	260	208	187	166	144	122	101
HY	12, 22, 34, 42, 52	260	191	166	141	120	99	79

AS Level only

Option	Components	Max	a	b	c	d	e
S1	11, 21, 31	130	96	88	77	66	55
S2	11, 21, 32	130	97	89	77	66	55
S3	12, 22, 33	130	83	70	60	50	41
S4	12, 22, 34	130	87	74	64	54	44
S5	13, 23, 35	130	94	86	75	65	55

Not shown: 13 further route(s) in the official table (staged entries that carry AS marks from an earlier series, or other special routes). See the official document.

Official documents: past papers, mark schemes and examiner report

March 2024

This March series (Papers 12, 22, 33, 42 and 52) covered glycosidic bonds, triglycerides and reducing sugars, membranes and cell signalling, nucleic acids and replication, transport in plants and mammals, immunity and monoclonal antibodies, Hardy-Weinberg, respiration, photosynthesis, and nerve and muscle physiology. Stronger scripts followed the command word, explained instead of describing, compared one feature at a time and used the material supplied. Weaker ones described where an explanation was wanted, answered only half of a two-part command, chose an option for its familiar keywords without reading all of it, and in the practical papers slipped on units, precision, replicates and critical values.

Where marks were lost:

• Paper 12: rate read from a y-axis value instead of a tangent; monoclonal antibodies treated as cells that divide; sieve tubes thought to lack mitochondria.
• Paper 22: sodium ions said to be too big for the bilayer rather than repelled by its hydrophobic core; T written in an RNA sequence; dissociation curves shifted up or down; only half of “state and explain” answered.
• Paper 33: units written in the table body; times recorded beyond the nearest second; plan diagrams too small or showing cells.
• Paper 42: Hardy-Weinberg rounded too early or stopped at 2pq; the reabsorption process described when the question asked about cell adaptations; comparisons with no similarities.
• Paper 52: chi-squared worked with expected ratios instead of expected numbers; the wrong critical value; Rf measured to the top of a spot, not its centre.

Grade thresholds – March 2024

Full A Level, all papers in this series

Option	Components	Max	A*	A	B	C	D	E
AY	12, 22, 33, 42, 52	260	196	175	154	131	109	87

AS Level only

Option	Components	Max	a	b	c	d	e
S3	12, 22, 33	130	90	80	68	56	45

Not shown: 7 further route(s) in the official table (staged entries that carry AS marks from an earlier series, or other special routes). See the official document.

Official documents: past papers, mark schemes and examiner report

November 2023

AS questions leaned on electron micrographs, protein and polysaccharide structure, Km and Vmax, RNA processing, membrane transport, plant transport, haemoglobin and infectious disease. Paper 4 tested chloroplasts, fermentation, Hardy-Weinberg and dihybrid crosses, meiosis, genetic technology, synapses and muscle, ADH and speciation. Candidates who did well carried their syllabus knowledge into unfamiliar settings and used the data given. Weaker scripts offered memorised general answers, missed details in the stem, and blurred pairs of terms such as cohesion and adhesion, guard cell and stoma, and thylakoid membrane and lumen.

Where marks were lost:

• Papers 11 to 13: mitosis confused with the whole cell cycle; injected antibodies called active immunity; SEM images taken for TEM; prokaryotes credited with mitosis.
• Papers 22 and 23: chromosome, chromatid and chromatin interchanged; mitochondria said to make energy; carboxyhaemoglobin for carbaminohaemoglobin; vaccines said to contain antibodies.
• Papers 41 and 43: q not square-rooted and pq used for 2pq in Hardy-Weinberg; an independent-assortment ratio read as linkage; thylakoid membrane and lumen merged.
• Paper 42: selective breeding mistaken for genetic engineering; cDNA confused with single-stranded DNA; ADH said to be made rather than secreted.
• Papers 31, 33, 34, 35 and 36: poor y-axis scales in most papers; drawing lines unjoined or too thick.
• Papers 51 to 53: significance read from standard deviation bars; wrong degrees of freedom; a single mean for the whole investigation; a null hypothesis about difference where correlation was tested.

Grade thresholds – November 2023

Full A Level, all papers in this series

Option	Components	Max	A*	A	B	C	D	E
AX	11, 21, 31, 41, 51	260	197	175	153	131	109	88
AY	12, 22, 33, 42, 52	260	184	163	142	120	99	78
AZ	13, 23, 35, 43, 53	260	190	168	146	125	104	83
HY	12, 22, 34, 42, 52	260	186	164	142	120	99	78
HZ	13, 23, 36, 43, 53	260	190	168	146	124	102	81

AS Level only

Option	Components	Max	a	b	c	d	e
S1	11, 21, 31	130	90	79	69	59	49
S3	12, 22, 33	130	86	75	65	55	46
S4	12, 22, 34	130	87	75	65	55	46
S5	13, 23, 35	130	83	72	62	53	44
S6	13, 23, 36	130	83	72	62	52	42

Not shown: 16 further route(s) in the official table (staged entries that carry AS marks from an earlier series, or other special routes). See the official document.

Official documents: past papers, mark schemes and examiner report

June 2023

The papers drew on cells in micrographs, polysaccharides, membrane transport, DNA replication and mitosis, T- and B-lymphocyte responses, carbon dioxide transport, plant transport, respiration, meiosis, chi-squared and Hardy-Weinberg, gene control, gene technology, and kidney, nerve and muscle physiology. Strong candidates annotated the stem, used the stimulus material, planned extended answers in a logical order and made paired comparisons. Weaker scripts wrote unordered bullet lists, mixed up replication with transcription and chromatids with chromosomes, misspelled terms so that the meaning changed, and gave rehearsed answers that did not fit the context.

Where marks were lost:

• Papers 11 to 13: telomeres placed on circular DNA; cellulose thought branched or helical; uracil called a purine; nuclei placed in sieve tubes.
• Paper 21: glycosidic bonds not named and cellulose given 1,6 bonds; glucose said to be too large to cross rather than polar; T cells said to secrete antibodies.
• Papers 22 and 23: cardiac cycle control described when asked to explain; DNA polymerase given transcription roles; magnification out by ten after measuring in centimetres.
• Papers 41 to 43: the dominant phenotype frequency taken as p squared; lac operon parts confused, with the repressor placed on the promoter; ultrafiltration explained as diffusion; NAD and FAD called enzymes.
• Papers 31 to 35 and 51 to 53: rate curves described without enzyme-substrate complexes; non-linear scales; one overall mean instead of one per level; “average” for mean.

Grade thresholds – June 2023

Full A Level, all papers in this series

Option	Components	Max	A*	A	B	C	D	E
AX	11, 21, 31, 41, 51	260	208	183	158	135	113	91
AY	12, 22, 33, 42, 52	260	195	171	147	125	104	83
AZ	13, 23, 35, 43, 53	260	201	179	157	136	115	94
HX	11, 21, 32, 41, 51	260	209	184	159	137	115	93
HY	12, 22, 34, 42, 52	260	196	172	148	126	105	84

AS Level only

Option	Components	Max	a	b	c	d	e
S1	11, 21, 31	130	95	85	72	59	47
S2	11, 21, 32	130	96	86	73	61	49
S3	12, 22, 33	130	87	76	65	55	45
S4	12, 22, 34	130	88	77	66	56	46
S5	13, 23, 35	130	93	84	74	64	54

Not shown: 16 further route(s) in the official table (staged entries that carry AS marks from an earlier series, or other special routes). See the official document.

Official documents: past papers, mark schemes and examiner report

March 2023

Papers 12, 22, 33, 42 and 52 covered lipid and protein bonding, collagen, membrane transport, water and plant transport, mammalian transport and gas exchange, infectious disease and immunity, gene expression and mutation, osmoregulation, respiration, meiosis, gene technology and statistics. The report says well-prepared candidates handled unfamiliar contexts with confidence. The main dividing line was careful reading of introductory text, axis labels and the exact wording of each question. Weaker scripts misread a key word and answered a different question, drew a textbook diagram instead of what the image showed, confused antibody with antibiotic, and described data where an explanation was needed.

Where marks were lost:

• Paper 12: secondary structure credited with covalent bonds; graticule calibration not rescaled for a new objective lens; competitive and non-competitive inhibition confused at high substrate concentration.
• Paper 22: a textbook membrane model drawn instead of the micrograph; loss of a whole triplet called a frameshift; T kept in RNA; cohesion and adhesion swapped.
• Paper 33: no working shown on the graph for a value read off it; drawing lines that did not meet; actual-size answers without units.
• Paper 42: ADH secretion said to rise as blood water potential rises; chromosomes drawn with two chromatids after anaphase II; gene-expression microarrays described when genome analysis was asked.
• Paper 52: serial dilution where proportional dilution was needed; “average” for mean; a significant decrease claimed from a test that ignores direction.

Grade thresholds – March 2023

Full A Level, all papers in this series

Option	Components	Max	A*	A	B	C	D	E
AY	12, 22, 33, 42, 52	260	190	167	144	122	100	79

AS Level only

Option	Components	Max	a	b	c	d	e
S3	12, 22, 33	130	87	75	64	53	42

Not shown: 8 further route(s) in the official table (staged entries that carry AS marks from an earlier series, or other special routes). See the official document.

Official documents: past papers, mark schemes and examiner report

November 2022

AS questions leaned on cell ultrastructure, protein structure, enzymes, viruses, the cell cycle, mutation, circulation, gas exchange tissues, water and sucrose transport, and infectious disease with immunity. At A Level the papers tested chemiosmosis in mitochondria and chloroplasts, genetic engineering set against gene therapy and gene editing, speciation, artificial selection, gibberellin and gene control, sex linkage, the nephron and ADH, and nerve and muscle. Strong scripts applied familiar ideas to new settings with precise, correctly spelled terms. Weak scripts copied the stem back, described when asked to explain or conclude, and swapped paired terms or levels of structure.

Where marks were lost:

• Papers 11 to 13: prokaryotes given mitochondria or a nucleus; facilitated diffusion said to need ATP; the AV node confused with Purkyne tissue.
• Papers 21 and 22: passive immunity taken as active; a gene said to code for one amino acid; Km said to rise with a non-competitive inhibitor; the collagen molecule confused with the fibre.
• Paper 23: disulfide bonds included despite the stem; the peptide bond drawn wrongly; a percentage decrease without a minus sign.
• Papers 41 to 43: protons and electrons muddled; “inner membrane space”; ATPase for ATP synthase; the lactate pathway given for yeast; sex-linked crosses without a key.
• Papers 31, 33, 34, 35 and 36: non-standard scales, thick lines and extrapolation; explanations with no active sites.
• Papers 51 to 53: control variables mistaken for a control; a “no correlation” null hypothesis for chi-squared; non-overlapping error bars taken as proof of significance.

Grade thresholds – November 2022

Full A Level, all papers in this series

Option	Components	Max	A*	A	B	C	D	E
AX	11, 21, 31, 41, 51	260	182	163	144	123	103	83
AY	12, 22, 33, 42, 52	260	184	158	132	110	88	66
AZ	13, 23, 35, 43, 53	260	178	159	140	120	100	81
HY	12, 22, 34, 42, 52	260	183	157	131	108	86	64
HZ	13, 23, 36, 43, 53	260	176	157	138	118	98	79

AS Level only

Option	Components	Max	a	b	c	d	e
S1	11, 21, 31	130	86	77	66	55	45
S3	12, 22, 33	130	87	72	61	50	39
S4	12, 22, 34	130	86	71	59	48	37
S5	13, 23, 35	130	82	73	63	53	43
S6	13, 23, 36	130	80	71	61	51	41

Not shown: 17 further route(s) in the official table (staged entries that carry AS marks from an earlier series, or other special routes). See the official document.

Official documents: past papers, mark schemes and examiner report

June 2022

The series gave weight to membrane transport and cotransport, enzyme kinetics and inhibition, changes to RNA after transcription, airway histology, antibodies, respiration and photosynthesis (chemiosmosis and coenzymes in particular), speciation, and using gene technology to compare genomes. Scripts that used the stem and applied knowledge flexibly did well. Weaker scripts recycled memorised lists that did not fit the scenario, treated genetic drift as natural selection, called the primary transcript mRNA, said NAD carries protons and gave one-sided differences. The practical and planning papers rewarded accurate drawings, sensible scales, full hazard, risk and precaution statements, and careful statistical wording.

Where marks were lost:

• Papers 11 to 13: facilitated diffusion thought to need ATP; centrioles confused with centromeres; where cilia, cartilage and each epithelium occur in the airways.
• Papers 21 to 23: primary transcript called mRNA; introns and exons reversed; stem cells said to divide straight into specialised cells with no self-renewal; the antigen-binding site called an active site.
• Paper 41: chloroplast chemiosmosis said to make no ATP, with protons flowing the wrong way; drift equated with selection; microarrays proposed for comparing alleles.
• Papers 42 and 43: ultrafiltration described as diffusion; ligand-gated and voltage-gated channels mixed up; percentage change divided by the final value; the two types of photophosphorylation compared without pairing.
• Papers 31 to 35: joined bars and unsuitable scales; in Paper 32, initial and final readings added instead of subtracted.
• Papers 51 to 53: p < 0.05 explained as chance or certainty; null hypotheses of the wrong type; risk dismissed without naming hazard, risk and precaution.

Grade thresholds – June 2022

Full A Level, all papers in this series

Option	Components	Max	A*	A	B	C	D	E
AW	12, 22, 33, 41, 52	260	185	164	143	120	98	76
AX	11, 21, 31, 41, 51	260	202	180	158	133	109	85
AY	12, 22, 33, 42, 52	260	176	154	132	109	86	64
AZ	13, 23, 35, 43, 53	260	190	171	152	132	112	92
HW	12, 22, 34, 41, 52	260	187	166	145	122	99	77
HX	11, 21, 32, 41, 51	260	200	178	156	131	106	82
HY	12, 22, 34, 42, 52	260	178	156	134	111	88	65

AS Level only

Option	Components	Max	a	b	c	d	e
S1	11, 21, 31	130	94	82	69	56	44
S2	11, 21, 32	130	92	80	67	54	41
S3	12, 22, 33	130	78	67	56	45	35
S4	12, 22, 34	130	80	69	58	47	36
S5	13, 23, 35	130	93	82	70	59	48

Not shown: 23 further route(s) in the official table (staged entries that carry AS marks from an earlier series, or other special routes). See the official document.

Official documents: past papers, mark schemes and examiner report

March 2022

Papers 12, 22, 33, 42 and 52 drew on protein and nucleic acid structure, water potential, chromosome behaviour in the cell cycle, Km and affinity, cardiac conduction, nerve impulses, inheritance with chi-squared, oxidative phosphorylation, speciation, classification and ecological statistics. Stronger scripts explained instead of describing, read graphs precisely, weighed both sides, named the transport process and applied knowledge to new material. Weaker scripts restated the stem, argued from misread data, drifted into a neighbouring topic (synapses instead of axons, transcription instead of replication), and ignored plain instructions on label lines, significant figures and ticks or crosses.

Where marks were lost:

• Paper 12: peptide bonds said to hold quaternary structure; hydrolysis thought to release water; osmotic equilibrium read as water no longer moving; monoclonal antibodies credited to lymphocytes rather than cloned hybridomas.
• Paper 22: daughter chromosomes drawn with two chromatids at anaphase; Km misread, then a contradictory affinity conclusion; uracil placed in DNA; the chloride shift explained by pH rather than charge balance.
• Paper 33: the independent-variable heading missing from tables; axis labels without units; drawing lines that did not meet.
• Paper 42: ATP credited with depolarisation instead of the ion pumping that restores the resting potential; chi-squared outcome reversed; allopatric speciation assumed with no barrier.
• Paper 52: an experimental control confused with a control variable; Simpson’s index rounded early or not subtracted from one; error bars drawn at half size.

Grade thresholds – March 2022

AS Level only

Option	Components	Max	a	b	c	d	e
S3	12, 22, 33	–	80	69	57	46	35

Not shown: 1 further route(s) in the official table (staged entries that carry AS marks from an earlier series, or other special routes). See the official document.

Official documents: past papers, mark schemes and examiner report

November 2021

The AS papers leaned on cells, biological molecules, membrane transport, transport in plants and mammals, and infectious disease. At A Level the questions covered the nephron and ADH, the Calvin cycle and C4 plants, respiration, gibberellin and DELLA proteins, inheritance, speciation, biodiversity sampling and genetic technology. Strong scripts used exact vocabulary: water vapour, water potential gradients, charged ions, and haemoglobin rather than red blood cells. Weaker scripts swapped paired terms such as cohesion and adhesion, antibody and antibiotic, and immunity and resistance, explained when asked to describe or predict, and missed information in the stem.

Where marks were lost:

• Papers 11 to 13: Benedict’s taken to identify one named sugar; uracil called a purine; sieve tubes said to be lignified; carboxyhaemoglobin said to carry carbon dioxide.
• Paper 21: cholera spread described without faecal contamination; transpiration described as loss of water rather than water vapour; amylose and amylopectin muddled.
• Papers 22 and 23: carrier proteins limited to active transport; thymine written into RNA; a progress curve misread as a Vmax plot.
• Papers 41 to 43: reduced FAD placed in glycolysis; the sodium-potassium pump confused with voltage-gated channels; sex-linked crosses without X and Y; gibberellin said to destroy DELLA directly.
• Papers 31, 33, 34, 35 and 36: a missing step in a serial dilution; non-linear scales; drawing lines that did not join.
• Papers 51 to 53: null hypothesis about difference when correlation was tested; Spearman’s justified from a syllabus list instead of the data; a negative coefficient compared by its sign.

Grade thresholds – November 2021

Full A Level, all papers in this series

Option	Components	Max	A*	A	B	C	D	E
AX	11, 21, 31, 41, 51	260	190	168	146	126	106	86
AY	12, 22, 33, 42, 52	260	198	173	148	124	100	76
AZ	13, 23, 35, 43, 53	260	189	164	139	120	101	82
HY	12, 22, 34, 42, 52	260	195	170	145	121	97	74
HZ	13, 23, 36, 43, 53	260	188	164	140	121	102	83

AS Level only

Option	Components	Max	a	b	c	d	e
S1	11, 21, 31	–	84	73	62	51	41
S3	12, 22, 33	–	86	74	62	50	39
S4	12, 22, 34	–	83	71	59	48	37
S5	13, 23, 35	–	80	66	56	46	37
S6	13, 23, 36	–	80	67	57	47	38

Not shown: 16 further route(s) in the official table (staged entries that carry AS marks from an earlier series, or other special routes). See the official document.

Official documents: past papers, mark schemes and examiner report

June 2021

Questions centred on water potential, Km, Vmax and inhibition, protein structure and bonding, transport in plants and mammals, infectious disease and immunity, respiration and photosynthesis, genetics and selection, and gene technology. Strong scripts obeyed the command word, used water-potential language, quoted data with units, compared directly and applied principles to new contexts. Weak scripts described when asked to explain, treated curved data as a straight line, wrote “matching” for complementary, and mixed near-identical terms: centromere and centrosome, genes and alleles, HIV and HIV/AIDS. The practical and planning papers rewarded precise graphs, clear dilutions and plans, and real evaluation.

Where marks were lost:

• Papers 11 to 13: magnification out by a factor of 10 or 100; resolution confused with magnification; the same shape chosen instead of a complementary one.
• Paper 21: osmosis data treated as linear; tonicity or water concentration used instead of water potential; plateaus blamed on denaturation; the malaria pathogen called a virus or bacterium.
• Papers 22 and 23: telophase for anaphase; centrosome for centromere; lignin put in sieve tubes; transcription described when translation was asked.
• Papers 41 to 43: a limiting-factor graph described rather than explained; ATP synthase said to pump protons; glycogenolysis confused with gluconeogenesis; genetic drift not described as random.
• Papers 51 to 53: dilutions without volumes; Km marked on the y-axis; non-overlapping error bars treated as proof.

Grade thresholds – June 2021

Full A Level, all papers in this series

Option	Components	Max	A*	A	B	C	D	E
AX	11, 21, 31, 41, 51	260	190	168	146	122	99	76
AY	12, 22, 33, 42, 52	260	187	164	141	117	93	70
AZ	13, 23, 35, 43, 53	260	200	177	154	130	107	84
HX	11, 21, 32, 41, 51	260	191	169	147	123	99	76
HY	12, 22, 34, 42, 52	260	185	162	139	115	92	69

AS Level only

Option	Components	Max	a	b	c	d	e
S1	11, 21, 31	–	87	75	62	49	36
S2	11, 21, 32	–	88	76	62	49	36
S3	12, 22, 33	–	88	77	65	53	42
S4	12, 22, 34	–	86	75	63	52	41
S5	13, 23, 35	–	92	80	67	54	41

Not shown: 10 further route(s) in the official table (staged entries that carry AS marks from an earlier series, or other special routes). See the official document.

Official documents: past papers, mark schemes and examiner report

March 2021

Papers 12, 22, 33, 42 and 52 covered cell structure and electron micrographs, water potential, enzymes, the immune response and disease control, ecology and conservation, mitochondrial respiration, meiosis, and gene technology such as microarrays. Some candidates knew the content well and could apply it to new contexts. The difference came from obeying the command word, following instructions exactly, answering every part of a multi-part question, and using precise terms and formulae. Weaker scripts wrote “white blood cell” instead of a named type, confused similar terms and wrote about the wrong process. In Paper 52, sampling design and statistics were the main weaknesses.

Where marks were lost:

• Paper 12: micrometre conversion in actual-size calculations; forgetting that chloroplasts and mitochondria have 70S ribosomes and their own DNA; channel proteins thought fixed in the membrane; condensation thought to use water.
• Paper 22: a curve described when asked to explain; cytokines confused with cytokinesis; ticks and crosses left out of some boxes.
• Paper 33: poorly chosen graph scales; lines too thick; drawing lines that did not meet.
• Paper 42: crossing over given where independent assortment was needed; ATPase for ATP synthase; troponin and tropomyosin swapped; mRNA said to be converted into cDNA; the wrong calcium ion charge.
• Paper 52: throwing quadrats treated as random sampling; recounting one quadrat as replication; the critical value read against degrees of freedom instead of the number of pairs.

Grade thresholds – March 2021

Full A Level, all papers in this series

Option	Components	Max	A*	A	B	C	D	E
AY	12, 22, 33, 42, 52	260	201	179	157	135	113	91

AS Level only

Option	Components	Max	a	b	c	d	e
S3	12, 22, 33	–	87	76	65	55	45

Not shown: 4 further route(s) in the official table (staged entries that carry AS marks from an earlier series, or other special routes). See the official document.

Official documents: past papers, mark schemes and examiner report

How to use this page

1. Find your gaps first. Take the free A Level diagnostic or AS diagnostic (all our diagnostics are listed on the diagnostics page), and tick off topics on the 9700 Biology checklist.
2. Sit one paper under timed conditions. Download it from Cambridge’s past-papers page. Check the paper’s front cover so you know which syllabus version it was set on, and look up the exam dates on our exam calendar.
3. Mark it strictly. Use the official mark scheme and our command words guide to check that each answer did what the question asked.
4. Read the notes for that series. Compare your lost marks with the “Where marks were lost” list above and with the recurring errors in What examiners keep saying.
5. Fix the topic. Use the notes and guides on the 9700 Biology subject hub, then practise with the 9700 self-check question bank.
6. Re-test. Sit a paper from a different series a week later. Use each series’ thresholds to see roughly where your mark sits, and see our grade thresholds page for the June 2026 thresholds for our flagship syllabuses.
7. Get help if a topic will not stick. Book a free trial lesson with one of our Biology teachers.

About these notes

Our sources are Cambridge’s grade-threshold tables and Principal Examiner Reports for Teachers for 9700, for the twelve series from March 2021 to November 2024 listed above; the notes are written in our own words. Thresholds change every series and must never be used to predict future ones. If you spot an error, please report a correction.