9700 AS & A Level Biology: past papers

Root hair cell structures, and the symplast and apoplast pathways for water crossing the root.

Controlling HIV transmission, magnification, and evidence that the opportunistic pathogen Pneumocystis is a eukaryote (cell wall, organelles).

Organelles of alveolar macrophages, and controlling tuberculosis with BCG vaccination programmes.

Liver blood supply, hepatocyte organelles, Kupffer cells removing old red cells, and peroxisomes vs mitochondria.

Controlling HIV transmission, magnification, and evidence that the opportunistic pathogen Pneumocystis is a eukaryote (cell wall, organelles).

Smooth muscle in airways and the gut wall, cell size and magnification, and what a gene mutation is.

Galactose compared with α-glucose, and analysing sugar content data for carrot varieties.

Fatty acids in olive oil: saturated and unsaturated chains, and the structure and variety of triglycerides.

Haemoglobin as a globular protein, and the substances involved in carrying oxygen and carbon dioxide in blood.

Using photosynthesis products, nitrate uptake by roots, and loading amino acids and sucrose into phloem.

Keratin structure with disulfide bonds, and comparing keratinase enzymes for temperature and pH range.

Non-competitive inhibition and Km for horseradish peroxidase, and start and stop codons in a synthetic gene.

Lysozyme and the induced-fit model, and comparing lysozyme with penicillin as antibacterial agents.

Keratin structure with disulfide bonds, and comparing keratinase enzymes for temperature and pH range.

The apoplast pathway and the Casparian strip, and active transport vs facilitated diffusion of potassium ions into root cells.

Using photosynthesis products, nitrate uptake by roots, and loading amino acids and sucrose into phloem.

Maintaining diffusion gradients in alveoli, ventilation, surfactant, and transcription and translation of a transporter gene.

Using antibodies on magnetic beads to collect stem cells, and making artificial red blood cells.

Adult stem cells, tissue repair by mitosis, tumour formation, telomeres, and blood cells formed from bone marrow stem cells.

Chromatin condensing into chromosomes during mitosis.

Chromatin and histones, chromosome structure at metaphase, and changes to chromosomes from S phase through mitosis.

Complementary base pairing between DNA and RNA nucleotides during transcription.

Non-competitive inhibition and Km for horseradish peroxidase, and start and stop codons in a synthetic gene.

Complementary base pairing between DNA and RNA nucleotides during transcription.

Smooth muscle in airways and the gut wall, cell size and magnification, and what a gene mutation is.

Maintaining diffusion gradients in alveoli, ventilation, surfactant, and transcription and translation of a transporter gene.

Root hair cell structures, and the symplast and apoplast pathways for water crossing the root.

The apoplast pathway and the Casparian strip, and active transport vs facilitated diffusion of potassium ions into root cells.

Using photosynthesis products, nitrate uptake by roots, and loading amino acids and sucrose into phloem.

Xylem vessel elements, cohesion-tension, and how xylem structure reduces resistance to flow.

Haemoglobin as a globular protein, and the substances involved in carrying oxygen and carbon dioxide in blood.

Malaria and the oxygen dissociation curve: standardising an experiment and the effect of a right shift on loading and unloading.

Liver blood supply, hepatocyte organelles, Kupffer cells removing old red cells, and peroxisomes vs mitochondria.

Tuberculosis species and transmission between people and animals, and spread to arteries.

HIV/AIDS and antiretroviral therapy, and a coronary artery bypass graft.

Tuberculosis: the pathogen, transmission, antibiotic treatment, and identifying airways and blood vessels in lung tissue.

Smooth muscle in airways and the gut wall, cell size and magnification, and what a gene mutation is.

Maintaining diffusion gradients in alveoli, ventilation, surfactant, and transcription and translation of a transporter gene.

Tuberculosis: the pathogen, transmission, antibiotic treatment, and identifying airways and blood vessels in lung tissue.

Controlling HIV transmission, magnification, and evidence that the opportunistic pathogen Pneumocystis is a eukaryote (cell wall, organelles).

Malaria and the oxygen dissociation curve: standardising an experiment and the effect of a right shift on loading and unloading.

Organelles of alveolar macrophages, and controlling tuberculosis with BCG vaccination programmes.

Lysozyme and the induced-fit model, and comparing lysozyme with penicillin as antibacterial agents.

HIV/AIDS and antiretroviral therapy, and a coronary artery bypass graft.

Tuberculosis species and transmission between people and animals, and spread to arteries.

Using antibodies on magnetic beads to collect stem cells, and making artificial red blood cells.

Adult stem cells, tissue repair by mitosis, tumour formation, telomeres, and blood cells formed from bone marrow stem cells.

Organelles of alveolar macrophages, and controlling tuberculosis with BCG vaccination programmes.

Blood lactate in a diving grey seal and anaerobic respiration.

Ethanol and lactate fermentation, why they regenerate NAD, and adaptations of rice to flooded fields.

The electron transport chain in the inner mitochondrial membrane, chemiosmosis and ATP synthesis.

Using DCPIP as a redox indicator to measure the effect of temperature on yeast respiration.

Oxygen entering the mitochondrion, the electron transport chain and ATP synthase, and mitochondrial DNA.

Chromatography of chloroplast pigments, the role of accessory pigments, and the light-independent stage.

Temperature and light intensity as limiting factors, and photolysis in non-cyclic photophosphorylation.

Non-cyclic photophosphorylation, uses of Calvin cycle intermediates, and temperature as a limiting factor.

Chromatography of chloroplast pigments, the role of accessory pigments, and the light-independent stage.

Temperature and light intensity as limiting factors, and photolysis in non-cyclic photophosphorylation.

Non-cyclic photophosphorylation, uses of Calvin cycle intermediates, and temperature as a limiting factor.

Ultrafiltration in the glomerulus and selective reabsorption in the proximal convoluted tubule.

Principles of homeostasis for blood glucose, and how a glycogen phosphorylase mutation affects glucagon signalling.

Osmoregulation: osmoreceptors, ADH and its effect on urine production.

ADH concentration after drinking water, and how the kidney responds.

Obtaining human genes for recombinant proteins, and producing insulin to treat diabetes.

Principles of homeostasis for blood glucose, and how a glycogen phosphorylase mutation affects glucagon signalling.

Negative feedback in blood glucose control, glucagon action, and urine test strips for glucose.

Glucagon and the enzyme cascade in liver cells, and testing glucose with urine strips and biosensors.

Maintaining a resting potential, and how low blood potassium changes an action potential.

Structure of a motor neurone, the neuromuscular junction and the order of events in muscle contraction.

Neurones and myelin, impulse transmission, and how morphine acts at a cholinergic synapse.

Mitochondria at neuromuscular junctions and in muscle, excitatory and inhibitory synapses, and multiple sclerosis.

Guard cell structure, daily rhythms of stomatal opening, and how stomata open and close.

Structure of a motor neurone, the neuromuscular junction and the order of events in muscle contraction.

Mitochondria at neuromuscular junctions and in muscle, excitatory and inhibitory synapses, and multiple sclerosis.

Meiosis, fertilisation and why a zygote is diploid with homologous chromosomes.

Continuous and discontinuous variation, causes of variation, and natural selection.

Causes of phenotypic variation and how variation allows evolution.

The yeast life cycle: budding by mitosis, meiosis and spores, and why diploid cells hide harmful recessive alleles.

Awns on rice grains: a dihybrid cross with epistasis and a chi-squared test.

A monohybrid genetic diagram for tomato fruit colour and the ratios from a dihybrid cross.

Colour patterns in tortoise beetles: genetic diagrams, codominance and a chi-squared test.

Gene, protein and phenotype in haemophilia, and gibberellin and stem height in peas.

A dihybrid cross in fruit flies with linked genes and a chi-squared test.

How genetic drift and the founder effect change allele frequencies.

Processes that change allele frequencies, and selective breeding of maize for vigour and uniform height.

Continuous and discontinuous variation, causes of variation, and natural selection.

Causes of phenotypic variation and how variation allows evolution.

Selective breeding of wheat for disease resistance.

Features of the kingdom Fungi, and how the partners in a lichen benefit each other.

Sampling plants with a frame quadrat, and testing for a correlation between plant height and altitude.

The yeast life cycle: budding by mitosis, meiosis and spores, and why diploid cells hide harmful recessive alleles.

Mark-release-recapture to estimate population size, and Himalayan balsam as an invasive species.

Why the red ruffed lemur is critically endangered, and captive breeding programmes in zoos.

An invasive toad in Madagascar, and IVF in conserving the eastern black rhino.

Mark-release-recapture to estimate population size, and Himalayan balsam as an invasive species.

Obtaining human genes for recombinant proteins, and producing insulin to treat diabetes.

Genetic engineering and gene therapy for an inherited eye disease, and why the eye suits gene therapy.

Fluorescent marker genes in genetic engineering, and DNA microarrays for gene expression.

Obtaining human genes for recombinant proteins, and producing insulin to treat diabetes.

Genetic engineering and gene therapy for an inherited eye disease, and why the eye suits gene therapy.

BRCA1 mutations, genetic screening and cancer risk, and survival data after drug treatment.

Fluorescent marker genes in genetic engineering, and DNA microarrays for gene expression.