Process
Edexcel A-Level Biology A 9BN0
Lifestyle, Health and Risk
Topic overviewWater and the carbohydratesCondensation, hydrolysis and glycosidic bondsLipids, food tests and unitsThe cardiac cycle and the structure of the heartArteries, veins and capillariesCore practical: caffeine and the heart rate of DaphniaThe blood clotting cascadeThrombus, embolus and their consequencesAtherosclerosis and the risk factors for CVDTreatments for CVD, and cholesterol transportBMI, waist-to-hip ratio and energy balanceCore practical 2: the vitamin C content of food and drinkCorrelation, causation and the design of health studiesRisk perception, and handling quantitative data
Genes and Health
Topic overviewGas exchange surfaces and Fick's LawThe fluid mosaic model of the cell membraneOsmosis, diffusion and active transportSurface area and volume calculationsThe structure of DNA and RNATranscriptionTranslation and the genetic codeAmino acids and the levels of protein structureGlobular and fibrous proteins: haemoglobin and collagenAlternative splicing and tissue-specific proteinsEnzyme specificity, the active site and activation energyRates of reaction, Vmax and Core Practical 4Semi-conservative replication and Meselson-StahlTypes of mutation and the CFTR geneAlleles, genotype and monohybrid inheritancePedigree diagrams and the inheritance of cystic fibrosisThe effects of cystic fibrosis, and the chi-squared testPrenatal genetic testing: PGD, amniocentesis and CVSThe ethics of genetic screening
Voice of the Genome
Topic overviewProkaryotic cellsEukaryotic organelles and their functionsIdentifying organelles in an electron micrographProtein secretion, and levels of organisationMicroscopy: the graticule, magnification and standard formThe cell cycle and the stages of mitosisCore practical: the root tip squashMeiosis, linkage and sex linkageThe structure of sperm and egg cellsFertilisation: the acrosome and cortical reactionsTotipotency, pluripotency and sources of stem cellsThe ethics and risks of stem cell therapyDifferential gene expression and specialisationThe lac operonEpigenetics: DNA methylation and histone modificationPolygenic inheritance, continuous variation and statistics
Biodiversity and Natural Resources
Topic overviewBiodiversity, species richness and the index of diversityNiches and the three kinds of adaptationNatural selection and evolutionThe Hardy-Weinberg equation and its assumptionsReproductive isolation and speciationClassificationThe plant cell wall, chloroplast and amyloplastThe vacuole, plasmodesmata, pits and middle lamellaPlant cells in the electron microscopeStarch and celluloseLignin, xylem vessels and sclerenchyma fibresIdentifying plant tissues under the microscopeThe structure of xylem, phloem and sclerenchymaWater and the mineral nutrition of plantsCore practical: investigating mineral deficiencyCore practical: the tensile strength of plant fibresDrug development from Withering to modern trialsGrowing bacteria and aseptic techniqueCore practical: the antimicrobial properties of plantsSustainability and Conservation
On the Wild Side
Topic overviewPhotosynthesis: the light-dependent reactionsPhotosynthesis: the Calvin cycleChloroplast structure and the products of photosynthesisProductivity: GPP, NPP and energy transferCore practicals on temperature and growthTemperature, enzymes and Q10Sampling: quadrats and transectsSuccessionBiotic and abiotic factors, niches and competitionEcosystem terms, evolution, speciation and validating evidenceEvidence for climate changeClimate models and their limitationsCorrelation, causation and scientific objectivityThe effects of climate change on organismsHuman activities that raise greenhouse gas levelsThe greenhouse effectEvolution and natural selectionSpeciationHow new scientific evidence is validatedThe carbon cycleReforestation, biofuels and sustainability
Immunity, Infection and Forensics
Topic overviewDecomposition, succession and forensic entomologyBody cooling and rigor mortisDNA profiling and the polymerase chain reactionGel electrophoresisThe structure of bacteria and virusesDecomposition, and how pathogens enter the bodyThe body's barriers, and modelling bacterial growthTuberculosis and HIVThe non-specific immune responseAntigens, antibodies and B cellsT cells and cell-mediated immunityActive and passive immunity, natural and artificialThe evolutionary race and pathogen evasionAntibiotics and testing their effectivenessHospital acquired infections and their control
Run for Your Life
Topic overviewMuscles and MovementThe myofibril and the sarcomereThe sliding filament theory, calcium and ATPSlow-twitch and fast-twitch muscle fibresGlycolysis and the link reactionThe Krebs cycle, oxidative phosphorylation and oxygen debtThe conduction system: SAN, AVN and Purkyne fibresThe sequence of cardiac excitationThe electrocardiogram, cardiac output and stroke volumeThe cardiovascular and ventilation control centresSpirometry and ventilation during exerciseHomeostasis, feedback and gene control by hormonesThermoregulation and the hypothalamusThe effects of too much and too little exerciseMedical technology and performance-enhancing substances
Grey Matter
Topic overviewThe structure of neurones and myelinationThe action potential and saltatory conductionThe structure of a synapse and calcium entryNeurotransmitter release and acetylcholineRod cells and the detection of lightEffectors, the neuromuscular junction and the pupil reflexPhytochrome and the response to lightIAA, phototropism and gravitropismNervous against hormonal coordinationThe regions of the brain and their functionsBrain imaging: MRI, fMRI, PET and CTCritical periods and the Hubel and Wiesel experimentsNature, nurture, habituation and research ethicsDopamine, serotonin and their imbalanceL-Dopa and MDMAGenome sequencing, personalised medicine and its ethicsGenetically modified organisms: benefits and risks
Lifestyle, Health and Risk
- 14 subtopics
- 42 things to know
- Papers 1, 2 and 3
What Lifestyle, Health and Risk covers
Covers the biological molecules the body is built from and the circulatory system that carries them: the cardiac cycle, blood vessels and clotting, how atherosclerosis develops, and how risk factors for cardiovascular disease are identified and treated.
Where it is assessed
Papers 1, 2 and 3
Core content, examined on every paper.
Check the Pearson Edexcel specification ↗The 14 subtopics
Each one has its own page.
- Water and the carbohydratesRecall questions on why water is a polar solvent, and on monosaccharides, disaccharides and the polysaccharides used for storage.Open →
- Condensation, hydrolysis and glycosidic bondsRecall questions on how monosaccharides join, the glycosidic bond, and how condensation and hydrolysis reverse one another.Open →
- Lipids, food tests and unitsRecall questions on triglycerides and ester bonds, saturated against unsaturated fatty acids, the food tests and their colour changes, and unit conversion.Open →
- The cardiac cycle and the structure of the heartRecall questions on why large organisms need mass transport, the three stages of the cardiac cycle, and the chambers, valves and vessels of the heart.Open →
- Arteries, veins and capillariesRecall questions on the wall structure and lumen of each vessel type, and on how each is suited to the pressure it carries.Open →
- Core practical: caffeine and the heart rate of DaphniaRecall questions on preparing Daphnia, the variables in the investigation, and the ethical considerations of using invertebrates.Open →
- The blood clotting cascadeRecall questions on thromboplastin, prothrombin, thrombin, fibrinogen and fibrin, and the order in which they act.Open →
- Thrombus, embolus and their consequencesRecall questions on why clots form inappropriately, and on what happens when a thrombus or embolus blocks an artery.Open →
- Atherosclerosis and the risk factors for CVDRecall questions on endothelial damage and plaque formation, and on genetics, diet, age, sex, blood pressure, smoking and inactivity as risk factors.Open →
- Treatments for CVD, and cholesterol transportRecall questions on antihypertensives, statins, anticoagulants and platelet inhibitors and their risks, and on the roles of HDL and LDL.Open →
- BMI, waist-to-hip ratio and energy balanceRecall questions on calculating BMI and waist-to-hip ratio, how exercise, stopping smoking and diet cut heart disease risk, energy balance, investigating vitamin C with DCPIP, basal metabolic rate, and calculating energy budgets and the fat gained from a surplus.Open →
- Core practical 2: the vitamin C content of food and drinkHow to find the vitamin C content of fruit juice by titrating it against DCPIP, which loses its blue colour as vitamin C reduces it: the calibration curve from known concentrations, the variables to control, and the sources of error in judging the end point.Open →
- Correlation, causation and the design of health studiesRecall questions on using illness and death figures to identify risk, correlation against causation, confounding variables and conflicting evidence, sample selection and size, validity and reliability, accuracy and precision, random and systematic error, and percentage error.Open →
- Risk perception, and handling quantitative dataRecall questions on why perceived risk differs from actual risk, measurement and instrumentation, serial dilutions and significant figures, choosing and reading graphs, estimating answers to check calculations, and the mathematical symbols and significance levels used in biology.Open →
What you need to know
Answer each one before you reveal it.
Your recallNot started
Process
What are the steps of the blood clotting cascade?
Numbers
State the formula for calculating body mass index (BMI) and define each term.
Key term
Define the term monosaccharide.
Key term
Define polysaccharide.
Key term
Define condensation reaction.
Key term
Define hydrolysis reaction.
Key term
What colour change indicates a positive result when testing for reducing sugars using Benedict's reagent?
Process
What is cardiac diastole?
Process
How does the lumen of a vein compare to its wall thickness?
Process
Why is it important that blood clots when a blood vessel is damaged?
Evaluation
Explain the mechanism by which statins reduce blood LDL cholesterol levels.
Evaluation
Describe the role of high-density lipoproteins (HDLs) in cholesterol transport.
Process
What happens when energy intake exceeds energy expenditure?
Evaluation
Define correlation in the context of health studies.
Evaluation
Why does sample selection affect the validity of health risk studies?
Process
Name six quantitative measurements that can be recorded using appropriate apparatus in practical work.
Key term
Why can calculated results only be reported to a limited number of significant figures?
Key term
State the glycerol component required to form a triglyceride.
Key term
How does the lumen of an artery compare to its wall thickness, and why is this significant?
Key term
How are Daphnia prepared for observation when investigating caffeine's effect on heart rate?
Key term
What is the independent variable when investigating caffeine's effect on Daphnia heart rate?
Key term
Why is fibrinogen described as a soluble protein while fibrin is insoluble?
Key term
What would happen to clot formation if a person lacked functional thrombin?
Process
What is the first stage in the development of atherosclerosis?
Key term
What happens at the site of endothelial damage following the initial dysfunction in atherosclerosis?
Key term
What is meant by describing water as a polar molecule?
Key term
What is a glycosidic bond?
Key term
State the fatty acid component required to form a triglyceride.
Key term
Why is diffusion alone insufficient to meet the needs of large organisms?
Key term
What is the function of elastic tissue in artery walls?
Key term
State four controlled variables in the Daphnia caffeine experiment.
Process
What initiates the blood clotting process?
Process
Explain why the clotting cascade involves multiple steps rather than a single reaction.
Key term
What three substances accumulate in the arterial wall to form an atheroma?
Key term
How do antihypertensives reduce CVD risk?
Numbers
Calculate the BMI when body mass = 61 kg, height = 2.01 m.
Key term
What is the principle behind using DCPIP to measure vitamin C?
Process
Why are repeats taken and anomalies discarded in the vitamin C practical?
Process
What safety precautions are needed in the vitamin C practical?
Key term
What does causation mean in health research?
Key term
How does people's perception of risk often compare to actual risk?
Take Lifestyle, Health and Risk further
The same content, four other ways.
Commonly confused
Pairs that lose marks when they are blurred together.
Correlation vs Causation
Correlation: association between two measured variables. Causation: one factor directly producing a change in another.
High-density lipoprotein vs Low-density lipoprotein
High-density lipoprotein: carrier transporting cholesterol towards the liver. Low-density lipoprotein: carrier transporting cholesterol from the liver to tissues.
Systole vs Diastole
Systole: phase when cardiac muscle contracts. Diastole: phase when cardiac muscle relaxes.
Questions from this topic
Each one with the model answer underneath.
- 1
What is meant by describing water as a polar molecule?
Model answer
Water has partial positive and partial negative charges on different parts of the molecule, giving it a dipole nature.
- 2
Why does water have a dipole nature?
Model answer
Oxygen is more electronegative than hydrogen, creating an uneven distribution of charge across the molecule.
- 3
How does the dipole nature of water enable it to act as an effective solvent for ionic substances?
Model answer
The partial charges on water molecules allow them to surround and separate charged particles, dissolving ionic and polar substances.
- 4
Name four substances dissolved in blood plasma that demonstrate water's role as a solvent in transport.
Model answer
Glucose, amino acids, ions and urea.
- 5
Define the term monosaccharide.
Model answer
A single sugar unit; the simplest form of carbohydrate.
- 6
What is a disaccharide?
Model answer
A carbohydrate formed from two monosaccharide units joined together.
What is inside Levo
Six ways to work the same material.
Lifestyle, Health and Risk revision questions
- What does Lifestyle, Health and Risk cover in Edexcel A-Level Biology A?
- 14 subtopics: water and the carbohydrates, condensation, hydrolysis and glycosidic bonds, lipids, food tests and units, the cardiac cycle and the structure of the heart, arteries, veins and capillaries, core practical: caffeine and the heart rate of daphnia, the blood clotting cascade, thrombus, embolus and their consequences, atherosclerosis and the risk factors for cvd, treatments for cvd, and cholesterol transport, bmi, waist-to-hip ratio and energy balance, core practical 2: the vitamin c content of food and drink, correlation, causation and the design of health studies and risk perception, and handling quantitative data. Each one has its own page with questions and model answers.
- How is Lifestyle, Health and Risk organised?
- By the Edexcel 9BN0 specification, subtopic by subtopic, so it matches the order you are taught it in.
Every question in Lifestyle, Health and Risk, on a schedule.
Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.
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