Evaluation
CCEA A-Level Biology 1010
Biological Molecules
Topic overviewWater as a solventInorganic ions and their rolesMonosaccharides and the glycosidic bondDisaccharides and polysaccharidesLipids, triglycerides and phospholipidsAmino acids and protein structureProtein shape, conjugated proteins and prionsNucleic acids: nucleotides, DNA and RNADNA replication and the Meselson–Stahl experimentBiochemical tests and paper chromatography
Enzymes
Topic overviewEnzymes as globular proteins and the active siteSpecificity, cofactors and coenzymesActivation energy and models of enzyme actionThe effect of temperature and pHThe effect of substrate and enzyme concentrationCompetitive and non-competitive inhibitionEnzymes as biomarkers of disease and inhibitors as drugsImmobilised enzymes and biosensors
Viruses and Cell Structure
Topic overviewBacteriophage and HIV structureViral replication in host cellsProkaryotic and eukaryotic cells comparedMembrane structure: the fluid mosaic modelFunctions of membrane componentsMitochondria and chloroplastsRibosomes, endoplasmic reticulum, Golgi apparatus and lysosomesThe nucleus, the cytoskeleton and plasmodesmataPlant, fungal and animal cellsMicroscopy, cell measurement and cell fractionation
Cell Physiology and Transport
Continuity of Cells
Topic overviewThe cell cycle: interphase and the gap phasesControl points in the cell cycle and cancerChromosome structure, haploidy and diploidyMitosis: the events of the four stagesCytokinesis and the significance of mitosisAnticancer drugs and the cell cycleMeiosis I and the first divisionMeiosis II and the significance of meiosisPreparing and examining slides of cell division
Tissues and Organs
Exchange Surfaces and Gas Exchange
Topic overviewSurface area, volume and the surface area to volume ratioFeatures of efficient exchange surfacesThe need for mass transport systemsFick's law and the rate of gas exchangeGas exchange in plants and the compensation pointGas exchange at the alveolusThe respiratory tree and the mechanism of ventilationThe effects of smoking on the breathing systemUsing a respirometer to measure gas exchange
Transport in Plants
Topic overviewEpidermis, endodermis and the tissues of the rootXylem vessels and their lignification patternsPhloem: sieve-tube elements and companion cellsWater and mineral ion uptake by root hairsThe apoplast and symplast pathwaysTranspiration and the factors affecting its rateCohesion-tension theory and the transpiration streamTranslocation of organic solutes in the phloemXerophytes and hydrophytes
The Circulatory System in Mammals
Topic overviewDouble circulation and the major blood vesselsThe structure and function of arteries, veins and capillariesAtherosclerosis, atheroma and the investigation of blood vesselsThe structure of the mammalian heartThe cardiac cycle and the operation of the valvesMyogenic stimulation and the electrocardiogramBlood cells and the stained blood filmPlasma, tissue fluid and blood clottingHaemoglobin and the oxygen dissociation curveThe Bohr effect, myoglobin and altitude
Adaptation and Biodiversity
Topic overviewAdaptation and the ways organisms meet environmental challengesEcological factors and the ecological nicheSampling procedures and sampling devicesEstimating abundance, density, frequency and percentage coverThe biochemical basis of life and the levels of biodiversityMeasuring species diversity with Simpson's indexHandling data: averages, spread and the t-testTaxonomy, nomenclature and the binomial systemThe concept of a speciesThe taxonomic hierarchy from genus to kingdomPhylogenetic taxonomy and molecular evidenceThe five kingdom system: prokaryotae, protoctista and fungiPlantae, animalia and alternative classification systems
Human Impact on Biodiversity
Topic overviewMonoculture, polyculture and intensive agricultureCrop rotation and hedgerow conservationPredator strips, pesticides and integrated pest managementOrganic pollution of waterways by slurry and silage effluentEutrophication and fertiliser run-offBiological oxygen demand and reducing aquatic pollutionConservation initiatives and habitat protectionGlobal warming, climate change and biodiversity
Homeostasis and Excretion
Topic overviewPrinciples of homeostasis and negative feedbackExcretion, osmoregulation and nitrogenous wasteGross structure of the kidney and the urinary systemStructure of the nephron and its blood supplyEpithelia of the nephron and their adaptationsThe glomerular filterUltrafiltration and the forces that drive itSelective reabsorption in the proximal convoluted tubuleThe loop of Henlé and the medullary salt gradientADH, osmoreceptors and the control of water balance
Immunity
Topic overviewNatural barriers to infectionAntigens, antibodies and the antigen–antibody reactionAntibody-mediated immunity and B-lymphocytesCell-mediated immunity and T-lymphocytesActive immunity, passive immunity and vaccinationTransplant rejection and immunosuppressionBlood group polymorphism and the rhesus factorTransfusion compatibility and its consequencesAntibiotic resistance and the search for new antimicrobialsELISA and the detection of disease biomarkers
Co-Ordination and Control
Topic overviewPhytochromes and the control of floweringPlant growth substances and stem elongationThe structure of a neuroneResting potential, threshold and the action potentialImpulse propagation and the speed of conductionSynapse structure and chemical transmissionExcitatory and inhibitory post-synaptic potentialsGross structure of the eye and accommodationThe retina, rods and conesSkeletal muscle and the sliding filament theory
Populations and Communities
Topic overviewPopulation growth curves, carrying capacity and environmental resistancer-selected and K-selected speciesInteractions between populationsBiological control of pest speciesPopulation dynamics and changes in population sizeEstimating population size in the field and the laboratoryCommunities and ecosystemsSuccession and climax communities
Ecological Energetics and Nutrient Cycling
Topic overviewFood chains, food webs and detritus food chainsTrophic levels, gross and net primary productionEcological pyramids and their usefulnessEnergy transfer efficiency between trophic levelsWhy energy is lost at each trophic levelImplications for agriculture and intensive farmingThe carbon cycleThe nitrogen cycle and the role of bacteria
Respiration
Topic overviewATP and the ATP/ADP cycleGlycolysisThe mitochondrion and the sites of aerobic respirationThe link reaction and the Krebs cycleThe electron transport chain and oxidative phosphorylationATP yield from one molecule of glucoseAnaerobic respiration in animals, plants and fungiAerobic and anaerobic respiration compared, and oxygen debtRespiratory quotient and measuring respiration
Photosynthesis
Topic overviewChloroplast structure and the sites of photosynthesisPhotosynthetic pigments and paper chromatographyAbsorption spectra and action spectraPhotosystems, photoactivation and the Z-schemePhotolysis of water, reduced NADP and redox indicatorsCarbon dioxide fixation and rubiscoReduction of glycerate phosphate and regeneration of ribulose bisphosphateLimiting factors, the compensation point and measuring photosynthesis
DNA as the Genetic Code
Topic overviewGenes and the nature of the genetic codeExons, introns and RNA splicingComparing DNA and RNATranscription and RNA polymeraseTransfer RNA, ribosomes and the sites of translationTranslation and polypeptide synthesisOne gene, one polypeptide and the control of the phenotypeEpigenetics, methylation and histone modification
Gene Technology
Topic overviewThe polymerase chain reactionDNA probes and genetic markersMicroarrays, pharmacogenetics and personalised medicineGenetic fingerprinting and gel electrophoresisThe stages of gene transferGenetically modified microorganismsTransgenic animals and plantsGene therapyGenome sequencing and the Human Genome ProjectGene inactivation and knockout organismsSocial, ethical and ecological issues of gene technology
Genes and Patterns of Inheritance
Topic overviewGenotype, phenotype and the environmentChromosomes, genes and allelesMonohybrid inheritance and Mendel's first lawCodominance, multiple alleles and lethal allelesTest crossesDihybrid inheritance and Mendel's second lawAutosomes, sex chromosomes and sex determinationGene interaction and epistasisPolygenic inheritance and continuous variationThe chi-squared test
Population Genetics and Evolution
Evolutionary Trends in Plants
Human Impact on Biodiversity
- 8 subtopics
- 24 things to know
- Unit AS 2
What Human Impact on Biodiversity covers
Human Impact on Biodiversity is examined in Unit AS 2, Organisms and Biodiversity, and drawn on again in Unit AS 3, the practical skills examination. It covers monoculture, polyculture and intensive agriculture, crop rotation and hedgerow conservation, predator strips, pesticides and integrated pest management, organic pollution of waterways by slurry and silage effluent, eutrophication and fertiliser run-off, biological oxygen demand and reducing aquatic pollution, conservation initiatives and habitat protection and global warming, climate change and biodiversity.
Where it is assessed
Unit AS 2
Organisms and Biodiversity, and again in Unit AS 3, Practical Skills in AS Biology.
Check the CCEA specification ↗The 8 subtopics
Each one has its own page.
- Monoculture, polyculture and intensive agricultureWhy monoculture reduces the biodiversity of farmland, why a pest can spread rapidly through a monoculture and intensive agriculture.Open →
- Crop rotation and hedgerow conservationCrop rotation, how rotating crops of different rooting depth benefits the soil and hedgerow as a habitat.Open →
- Predator strips, pesticides and integrated pest managementPredator strip at a field margin, how an uncultivated strip beside a watercourse protects that watercourse and why a broad-spectrum pesticide reduces biodiversity.Open →
- Organic pollution of waterways by slurry and silage effluentSilage effluent, how organic pollution reaches a waterway from a farm and two invertebrates that indicate clean, well-oxygenated water.Open →
- Eutrophication and fertiliser run-offHow nitrate applied to a field reaches a nearby river, algal bloom and why leaving soil bare over winter increases nutrient loss.Open →
- Biological oxygen demand and reducing aquatic pollutionBiological oxygen demand, why the sample must be incubated in complete darkness and why the sample bottle must be filled completely and sealed.Open →
- Conservation initiatives and habitat protectionArea of Special Scientific Interest, special Area of Conservation and biodiversity Action Plan.Open →
- Global warming, climate change and biodiversityGlobal warming, climate change and local extinction.Open →
What you need to know
Answer each one before you reveal it.
Your recallNot started
Key term
Explain why the effects of climate change on biodiversity are difficult to predict.
Key term
What is crop rotation?
Key term
What is a predator strip at a field margin?
Key term
What is slurry?
Key term
Define eutrophication.
Key term
Describe how the biological oxygen demand of a water sample is measured.
Key term
What protection does designation as an Area of Special Scientific Interest give a site?
Key term
What is monoculture?
Key term
How does including a legume in a rotation improve soil fertility?
Key term
Give one benefit of a field margin strip other than pest control.
Key term
What is silage effluent?
Key term
Which two mineral ions from fertilisers are chiefly responsible for eutrophication?
Key term
Explain why a sample for measuring biological oxygen demand must be incubated in complete darkness
Key term
Explain the value of protected sites forming a network rather than standing alone.
Key term
What is meant by global warming?
Key term
What is polyculture?
Key term
Explain how rotating crops of different rooting depth benefits the soil.
Key term
Explain how an uncultivated strip beside a watercourse protects that watercourse.
Key term
Describe what happens to the numbers of bacteria in a river receiving slurry.
Key term
Explain how nitrate applied to a field reaches a nearby river.
Key term
Explain why the bottle for a biological oxygen demand sample must be filled completely and sealed
Key term
Why are Biodiversity Action Plans drawn up for individual district council areas?
Key term
What is meant by climate change?
Take Human Impact on Biodiversity further
The same content, four other ways.
Questions from this topic
Each one with the model answer underneath.
- 1
What is monoculture?
Model answer
Monoculture is the growing of a single crop species over a large area of land, often in the same fields year after year.
- 2
What is polyculture?
Model answer
Polyculture is the growing of several different crop species together or within the same area of land.
- 3
Give two economic advantages of monoculture to a farmer.
Model answer
One crop allows the whole farm to be worked with a single set of specialised machinery, and the large uniform harvest is easier and cheaper to sell.
- 4
Explain why monoculture reduces the biodiversity of farmland.
Model answer
A single crop species offers only one kind of habitat and one kind of food, so only the few species able to use that crop can survive there.
- 5
Explain why a pest can spread rapidly through a monoculture.
Model answer
Every plant in the field is the same species, so a pest that can attack one plant can attack them all and its food supply is unbroken across the whole area.
- 6
Explain how polyculture makes it harder for a pest to build up large numbers.
Model answer
The plants a pest can feed on are scattered among other species, so the pest must travel further between them and its population grows more slowly.
What is inside Levo
Six ways to work the same material.
Human Impact on Biodiversity revision questions
- What does Human Impact on Biodiversity cover in CCEA A-Level Biology?
- 8 subtopics: monoculture, polyculture and intensive agriculture, crop rotation and hedgerow conservation, predator strips, pesticides and integrated pest management, organic pollution of waterways by slurry and silage effluent, eutrophication and fertiliser run-off, biological oxygen demand and reducing aquatic pollution, conservation initiatives and habitat protection and global warming, climate change and biodiversity. Each one has its own page with questions and model answers.
- How is Human Impact on Biodiversity organised?
- By the CCEA 1010 specification, subtopic by subtopic, so it matches the order you are taught it in.
Every question in Human Impact on Biodiversity, 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.
Or £46 a year, about £3.83 a month. Cancel anytime.