Unit AS 1
Molecules and Cells
- BIOLOGICAL MOLECULES
- ENZYMES
- VIRUSES AND CELL STRUCTURE
- CELL PHYSIOLOGY AND TRANSPORT
- CONTINUITY OF CELLS
- TISSUES AND ORGANS
1 hour 30 minutesstructured questions and an essay15% of the A level
CCEA AS Biology, memorised in year one.
Everything the AS examines and nothing from the second year. Drill the 11 topics you are actually sitting in Northern Ireland this summer.
- AS of 1010
- 11 topics
- 100 subtopics
CCEA AS-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
What CCEA AS Biology covers, and what it leaves out
CCEA AS Biology is the first year of the 1010 course and a qualification in its own right, examined in 2 units, Unit AS 1 and Unit AS 2. This page holds only what the AS examines: 11 topics across 100 subtopics, 1,424 active recall questions, starting with Biological Molecules, Enzymes and Viruses and Cell Structure. The 13 topics kept back for the second year are not shown, so nothing here is content you have not been taught yet.
Starting the second year? The full CCEA A-Level Biology page adds the A2 topics on top of everything here.
CCEA GCE Biology, subject code 1010, qualification number 601/8487/5 at A level and 601/8486/3 at AS, first teaching September 2016. Read the CCEA specification ↗
How it is assessed
Unit AS 2
Organisms and Biodiversity
- EXCHANGE SURFACES AND GAS EXCHANGE
- TRANSPORT IN PLANTS
- THE CIRCULATORY SYSTEM IN MAMMALS
- ADAPTATION AND BIODIVERSITY
- HUMAN IMPACT ON BIODIVERSITY
1 hour 30 minutesstructured questions and an essay15% of the A level
Unit AS 3
Practical Skills in AS Biology
- BIOLOGICAL MOLECULES
- ENZYMES
- VIRUSES AND CELL STRUCTURE
- CELL PHYSIOLOGY AND TRANSPORT
- CONTINUITY OF CELLS
- TISSUES AND ORGANS
- EXCHANGE SURFACES AND GAS EXCHANGE
- TRANSPORT IN PLANTS
- THE CIRCULATORY SYSTEM IN MAMMALS
- ADAPTATION AND BIODIVERSITY
- HUMAN IMPACT ON BIODIVERSITY
1 hour, plus internally assessed practical workpractical skills10% of the A level
The full specification
11 topics, 100 subtopics. Open any topic to see what is inside it.
01Biological Molecules10 subtopicsOpen topic
- Water as a solvent
- Inorganic ions and their roles
- Monosaccharides and the glycosidic bond
- Disaccharides and polysaccharides
- Lipids, triglycerides and phospholipids
- Amino acids and protein structure
- Protein shape, conjugated proteins and prions
- Nucleic acids: nucleotides, DNA and RNA
- DNA replication and the Meselson–Stahl experiment
- Biochemical tests and paper chromatography
02Enzymes8 subtopicsOpen topic
- Enzymes as globular proteins and the active site
- Specificity, cofactors and coenzymes
- Activation energy and models of enzyme action
- The effect of temperature and pH
- The effect of substrate and enzyme concentration
- Competitive and non-competitive inhibition
- Enzymes as biomarkers of disease and inhibitors as drugs
- Immobilised enzymes and biosensors
03Viruses and Cell Structure10 subtopicsOpen topic
- Bacteriophage and HIV structure
- Viral replication in host cells
- Prokaryotic and eukaryotic cells compared
- Membrane structure: the fluid mosaic model
- Functions of membrane components
- Mitochondria and chloroplasts
- Ribosomes, endoplasmic reticulum, Golgi apparatus and lysosomes
- The nucleus, the cytoskeleton and plasmodesmata
- Plant, fungal and animal cells
- Microscopy, cell measurement and cell fractionation
04Cell Physiology and Transport7 subtopicsOpen topic
05Continuity of Cells9 subtopicsOpen topic
- The cell cycle: interphase and the gap phases
- Control points in the cell cycle and cancer
- Chromosome structure, haploidy and diploidy
- Mitosis: the events of the four stages
- Cytokinesis and the significance of mitosis
- Anticancer drugs and the cell cycle
- Meiosis I and the first division
- Meiosis II and the significance of meiosis
- Preparing and examining slides of cell division
06Tissues and Organs7 subtopicsOpen topic
07Exchange Surfaces and Gas Exchange9 subtopicsOpen topic
- Surface area, volume and the surface area to volume ratio
- Features of efficient exchange surfaces
- The need for mass transport systems
- Fick's law and the rate of gas exchange
- Gas exchange in plants and the compensation point
- Gas exchange at the alveolus
- The respiratory tree and the mechanism of ventilation
- The effects of smoking on the breathing system
- Using a respirometer to measure gas exchange
08Transport in Plants9 subtopicsOpen topic
- Epidermis, endodermis and the tissues of the root
- Xylem vessels and their lignification patterns
- Phloem: sieve-tube elements and companion cells
- Water and mineral ion uptake by root hairs
- The apoplast and symplast pathways
- Transpiration and the factors affecting its rate
- Cohesion-tension theory and the transpiration stream
- Translocation of organic solutes in the phloem
- Xerophytes and hydrophytes
09The Circulatory System in Mammals10 subtopicsOpen topic
- Double circulation and the major blood vessels
- The structure and function of arteries, veins and capillaries
- Atherosclerosis, atheroma and the investigation of blood vessels
- The structure of the mammalian heart
- The cardiac cycle and the operation of the valves
- Myogenic stimulation and the electrocardiogram
- Blood cells and the stained blood film
- Plasma, tissue fluid and blood clotting
- Haemoglobin and the oxygen dissociation curve
- The Bohr effect, myoglobin and altitude
10Adaptation and Biodiversity13 subtopicsOpen topic
- Adaptation and the ways organisms meet environmental challenges
- Ecological factors and the ecological niche
- Sampling procedures and sampling devices
- Estimating abundance, density, frequency and percentage cover
- The biochemical basis of life and the levels of biodiversity
- Measuring species diversity with Simpson's index
- Handling data: averages, spread and the t-test
- Taxonomy, nomenclature and the binomial system
- The concept of a species
- The taxonomic hierarchy from genus to kingdom
- Phylogenetic taxonomy and molecular evidence
- The five kingdom system: prokaryotae, protoctista and fungi
- Plantae, animalia and alternative classification systems
11Human Impact on Biodiversity8 subtopicsOpen topic
- 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
- Global warming, climate change and biodiversity
How you work through it
Pick the mode that fits the time you have.
Try three questions
No account needed. Answer from memory first.
Your recallNot started
Key term
How was the DNA separated in the Meselson and Stahl experiment, and what did each generation's result rule out?
Key term
How does a fibrous protein differ from a globular one, and what does each kind do?
Key term
Why is a water molecule described as polar?
Spaced Repetition Schedule
How reviews are timed
Levo will automatically distribute all of your progress into a spaced repetition calendar. Once you’ve answered, it’s scheduled for you on the next day in the spaced repetition schedule. Over time, the gaps between your recall get bigger, from a day to three years, reinforcing memorisation over a long period of time.
Interval sequence
- 1 day
- 3 days
- 7 days
- 14 days
- 30 days
- 60 days
- 4 months
- 8 months
- 1 year
- 2 years
- 3 years
What is inside Levo
Six ways to work the same material
Biology revision questions
Common questions about revising CCEA AS-Level Biology. Tap any to open it.
What is on CCEA AS Biology?
11 topics across 100 subtopics, examined in Unit AS 1 and Unit AS 2. They are all listed on this page, and each one opens to the subtopics inside it. The full topic list is Biological Molecules, Enzymes, Viruses and Cell Structure, Cell Physiology and Transport, Continuity of Cells, Tissues and Organs and more.
Does AS Biology count towards the full A level?
Yes. In Northern Ireland the AS units are marked as a standalone AS qualification and also carry forward into the full CCEA A level, which is why the first year matters more here than it does in England. Check the current weighting on the 1010 specification, as it is set by the board rather than by us.
What is the difference between AS and A level Biology?
AS is the first-year units only. The A level adds 13 further topics, among them Homeostasis and Excretion, Immunity, Co-Ordination and Control, and expects you to connect them back to the AS material. Work the AS content here, then move up to the full A level page when you start the second year.
When do you sit CCEA AS Biology?
Normally at the end of Year 12, in the summer series. That gives you one year to memorise 1,424 questions' worth of material, which is roughly 7 questions a day across an academic year if you start in September.
How should you revise for AS Biology?
By retrieval, not rereading. Cover the answer, pull it from memory, then check. Levo runs that loop across all 11 AS topics and brings each question back on a spaced schedule, so what you learn in September is still there in June.
Is it worth revising AS content again for the A level?
Yes, and it is the mistake most students make. The second-year papers assume the first year, and in Northern Ireland the AS marks usually count towards the final grade as well. Keeping the AS material on a spaced schedule through Year 13 costs far less time than relearning it.
How many questions are there for CCEA AS Biology?
1,424, written from the 1010 subject content and grouped into 100 subtopics so you can work one small area at a time rather than a whole topic at once.
Can you use Levo for just the AS year?
Yes. Pick your subject, choose the AS topics on the topic screen, and every mode — the 3-step method, Cram, Blank Blitz, Build It and Test It — works only that material. Add the second-year topics when you get to them.
Every question in Biology, 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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