Specification points
Edexcel A-level Biology B 9BI0
302 points in 10 topics, with Edexcel's codes and titles.
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Codes and titles are read by a script from Edexcel's published specification and have not been checked by a person. What each point covers is in the specification itself: Edexcel’s specification.
1 Biological Molecules
- 1.1 Carbohydrates
- 1.1(i) Mono-, di- and polysaccharides
- 1.1(ii) Structure of glucose and ribose
- 1.1(iii) Formation of disaccharides and polysaccharides
- 1.1(iv) Carbohydrate structure and function
- 1.2 Lipids
- 1.2(i) Synthesis of triglycerides
- 1.2(ii) Saturated and unsaturated lipids
- 1.2(iii) Lipid structure and roles
- 1.2(iv) Phospholipids in cell membranes
- 1.3 Proteins
- 1.3(i) Structure of an amino acid
- 1.3(ii) Formation of polypeptides and proteins
- 1.3(iii) Bonds in protein structure
- 1.3(iv) Levels of protein structure
- 1.3(v) Structure and function of collagen and haemoglobin
- 1.4 DNA and protein synthesis
- 1.4(i) Structure of DNA
- 1.4(ii) Semi-conservative DNA replication
- 1.4(iii) Genes as base sequences
- 1.4(iv) Structure of mRNA
- 1.4(v) Structure of tRNA
- 1.4(vi) Transcription and translation
- 1.4(vii) Nature of the genetic code
- 1.4(viii) Gene mutations: deletions, insertions and substitutions
- 1.4(ix) Point mutations and sickle cell anaemia
- 1.5 Enzymes
- 1.5(i) Enzymes as globular proteins
- 1.5(ii) Enzyme specificity and induced fit
- 1.5(iii) Enzymes lowering activation energy
- 1.5(iv) Factors affecting enzyme activity
- CP1 Investigate a factor affecting the initial rate of an enzyme–controlled reaction
- 1.5(v) Measuring initial rate of enzyme activity
- 1.5(vi) Enzyme inhibition
- 1.5(vii) Intracellular and extracellular enzyme reactions
- 1.6 Inorganic ions
- 1.6(i) Roles of inorganic ions in plants
- 1.7 Water
- 1.7(i) Properties of water and their significance
2 Cells, Viruses and Reproduction of Living Things
- 2.1 Eukaryotic and prokaryotic cell structure and function
- 2.1(i) Cell theory
- 2.1(ii) Cells, tissues, organs and organ systems
- 2.1(iii) Ultrastructure of prokaryotic cells
- 2.1(iv) Gram positive and Gram negative bacteria
- 2.1(v) Ultrastructure of eukaryotic cells
- 2.1(vi) Light and electron microscopy
- 2.1(vii) Staining specimens in microscopy
- CP2 Core practical: light microscope and eyepiece micrometers
- 2.2 Viruses
- 2.2(i) Classification of viruses
- 2.2(ii) The lytic cycle and latency
- 2.2(iii) Viruses and antiviral drugs
- 2.2(iv) Controlling the spread of viral disease
- 2.2(v) Ethics of untested drugs in epidemics
- 2.3 Eukaryotic cell cycle and division
- 2.3(i) The cell cycle
- 2.3(ii) Genetic material in the cell cycle and mitosis
- 2.3(iii) Roles of mitosis
- CP3 Core practical: root tip squash and stages of mitosis
- 2.3(iv) Meiosis and haploid gametes
- 2.3(v) Meiosis and genetic variation
- 2.3(vi) Chromosome mutations
- 2.3(vii) Non-disjunction: polysomy and monosomy
- 2.4 Sexual reproduction in mammals
- 2.4(i) Oogenesis and spermatogenesis
- 2.4(ii) Events of fertilisation
- 2.4(iii) Early embryo development
- 2.5 Sexual reproduction in plants
- 2.5(i) Formation of pollen grains and the embryo sac
- 2.5(ii) Pollen tube growth and male nuclei reaching the embryo sac
- CP4 Investigate the effect of sucrose concentrations on pollen tube growth or germination
- 2.5(iii) Double fertilisation in flowering plants
3 Classification and Biodiversity
- 3.1 Classification
- 3.1(i) The classification hierarchy
- 3.1(ii) Limitations of the species definition
- 3.1(iii) Difficulties in assigning and identifying species
- 3.1(iv) Gel electrophoresis in classification
- 3.1(v) DNA sequencing and bioinformatics in classification
- 3.1(vi) Scientific community validating evidence for evolution
- 3.1(vii) Three-domain versus five-kingdom classification
- 3.2 Natural selection
- 3.2(i) Evolution by natural selection
- 3.2(ii) Niches and adaptations
- 3.2(iii) Allopatric and sympatric speciation
- 3.2(iv) Evolutionary race between pathogens and medicines
- 3.3 Biodiversity
- 3.3(i) Measuring biodiversity at different scales
- 3.3(ii) Ethical and economic reasons to maintain biodiversity
- 3.3(iii) In-situ and ex-situ conservation
4 Exchange and Transport
- 4.1 Surface area to volume ratio
- 4.1(i) Surface area to volume ratio and transport
- 4.1(ii) Need for mass transport and gas exchange surfaces
- 4.2 Cell transport mechanisms
- 4.2(i) Cell membrane and the fluid mosaic model
- 4.2(ii) Passive transport: diffusion, facilitated diffusion, osmosis
- 4.2(iii) Molecular properties affecting transport
- 4.2(iv) Endocytosis and exocytosis
- CP5 Investigate the effect of temperature on beetroot membrane permeability
- CP6 Determine the water potential of plant cells
- 4.2(v) Active transport and ATP
- 4.2(vi) ATP as an energy supply
- 4.3 Gas exchange
- 4.3(i) Gas exchange in insects, fish and mammals
- CP7 Core practical: dissecting an insect's gas exchange system
- 4.3(ii) Gas exchange in flowering plants
- 4.4 Circulation
- 4.4(i) Structure of the heart and blood vessels
- 4.4(ii) Double versus single circulatory systems
- 4.4(iii) The cardiac cycle
- 4.4(iv) Myogenic stimulation of the heart
- 4.4(v) Interpreting ECG traces and cardiac pressure changes
- 4.4(vi) Structure of blood
- 4.4(vii) Functions of blood
- 4.4(viii) Platelets, plasma proteins and blood clotting
- 4.4(ix) Atherosclerosis: stages, effects and risk factors
- 4.5 Transport of gases in the blood
- 4.5(i) Haemoglobin and the Bohr effect
- 4.5(ii) Oxygen dissociation curve of haemoglobin
- 4.5(iii) Haemoglobin and myoglobin compared
- 4.5(iv) Fetal and adult haemoglobin
- 4.6 Transfer of materials between the circulatory system and cells
- 4.6(i) Formation and reabsorption of tissue fluid
- 4.6(ii) Tissue fluid returned via the lymph
- 4.7 Transport in plants
- 4.7(i) Structure of xylem and phloem
- 4.7(ii) Apoplastic and symplastic pathways
- 4.7(iii) Cohesion-tension model of water transport
- 4.7(iv) Factors affecting transpiration rate
- 4.7(v) Mass-flow hypothesis for phloem transport
- CP8 Investigate factors affecting water uptake by plant shoots using a potometer
5 Energy for Biological Processes
- 5.1 Aerobic respiration
- 5.1(i) Cellular respiration yielding ATP and heat
- 5.1(ii) Stages of aerobic respiration
- 5.2 Glycolysis
- 5.2(i) Conversion of monosaccharides to pyruvate
- 5.3 Link reaction and Krebs cycle
- 5.3(i) Site of the link reaction and Krebs cycle
- 5.3(ii) Link reaction and Krebs cycle products
- 5.4 Oxidative phosphorylation
- 5.4(i) Site of the electron transport chain
- 5.4(ii) Electron transport chain and oxidative phosphorylation
- 5.4(iii) Oxygen as the terminal electron acceptor
- 5.4(iv) ATP synthesis by chemiosmosis
- 5.4(v) Importance of mitochondrial membranes
- 5.5 Anaerobic respiration
- 5.5(i) Partial breakdown of hexoses without oxygen
- 5.5(ii) ATP yields of aerobic and anaerobic respiration
- 5.5(iii) Lactate and muscle contraction
- 5.5(iv) Ethanol formation in plants
- CP9 Core practical: rate of respiration using a respirometer
- 5.6 Photosynthetic pigments
- 5.6(i) Absorption and action spectra
- CP10 Core practical: wavelength of light and photosynthesis
- 5.6(ii) Variety of photosynthetic pigments
- CP11 Investigate the presence of different chloroplast pigments using chromatography
- 5.7 Photosynthesis
- 5.7(i) Structure of chloroplasts
- 5.7(ii) Thylakoid membranes in the light-dependent stage
- 5.7(iii) Cyclic and non-cyclic photophosphorylation
- 5.7(iv) Stroma in the light-independent stage
- 5.7(v) Carbon fixation by RUBISCO
- 5.7(vi) Use of ATP and reduced NADP in the Calvin cycle
- 5.7(vii) GALP as a raw material
- 5.7(viii) Limiting factors of photosynthesis
6 Microbiology and Pathogens
- 6.1 Microbial techniques
- 6.1(i) Aseptic techniques
- 6.1(ii) Culturing microorganisms
- 6.1(iii) Culture media
- 6.1(iv) Measuring bacterial growth
- 6.1(v) Bacterial growth curves and growth rate constants
- CP12 Core practical: growth of bacteria in liquid culture
- CP13 Core practical: isolating bacteria by streak plating
- 6.2 Bacteria as pathogens
- 6.2(i) Bacteria as agents of infection
- 6.2(ii) Exotoxins, endotoxins and tissue invasion
- 6.3 Action of antibiotics
- 6.3(i) Bactericidal and bacteriostatic antibiotics
- 6.4 Antibiotic resistance
- 6.4(i) Development and spread of antibiotic resistance
- 6.4(ii) Controlling antibiotic resistance
- 6.5 Other pathogenic agents
- 6.5(i) Transmission and effects of named pathogens
- 6.6 Problems of controlling endemic diseases
- 6.6(i) Implications of malaria control methods
- 6.7 Response to infection
- 6.7(i) Macrophages, neutrophils and lymphocytes
- 6.7(ii) The humoral immune response
- 6.7(iii) The cell-mediated immune response
- 6.7(iv) Memory cells and the secondary immune response
- 6.7(v) Natural, artificial, active and passive immunity
- 6.7(vi) Vaccination and herd immunity
- 6.7(vii) Issues when people choose not to vaccinate
7 Modern Genetics
- 7.1 Using gene sequencing
- 7.1(i) The genome
- 7.1(ii) PCR and uses of amplified DNA
- 7.2 Factors affecting gene expression
- 7.2(i) Transcription factors binding to DNA
- 7.2(ii) Transcription factors regulating gene expression
- 7.2(iii) RNA splicing
- 7.2(iv) Epigenetic modification of gene expression
- 7.2(v) Epigenetics and cell differentiation
- 7.3 Stem cells
- 7.3(i) Totipotent, pluripotent and multipotent stem cells
- 7.3(ii) Embryonic stem cells: medical uses and ethics
- 7.3(iii) Epigenetics in embryonic cell differentiation
- 7.3(iv) Induced pluripotent stem cells
- 7.3(v) iPS cells compared with embryonic stem cells
- 7.4 Gene technology
- 7.4(i) Producing recombinant DNA
- 7.4(ii) Vectors for inserting recombinant DNA
- 7.4(iii) Marker genes and replica plating
- 7.4(iv) Knockout mice as animal models
- 7.4(v) Genetic modification of soya beans
- 7.4(vi) Public debate on genetically modified crops
8 Origins of Genetic Variation
- 8.1 Origins of genetic variation
- 8.1(i) Mutation and meiosis as sources of variation
- 8.1(ii) Random fertilisation and genetic variation
- 8.2 Transfer of genetic information
- 8.2(i) Terms used in inheritance
- 8.2(ii) Genetic crosses and pedigree diagrams
- 8.2(iii) Inheritance of two unlinked genes
- 8.2(iv) Autosomal linkage
- 8.2(v) Sex linkage and haemophilia
- 8.2(vi) Chi squared test
- 8.3 Gene pools
- 8.3(i) Types of selection and allele frequencies
- 8.3(ii) Genetic drift
- 8.3(iii) Population bottlenecks and the founder effect
- 8.3(iv) Hardy–Weinberg equation
9 Control Systems
- 9.1 Homeostasis
- 9.1(i) Homeostasis as dynamic equilibrium
- 9.1(ii) Maintaining pH, temperature and water potential
- 9.1(iii) Negative and positive feedback
- 9.2 Chemical control in mammals
- 9.2(i) Hormone production and action on target cells
- 9.2(ii) Two modes of hormone action
- 9.3 Chemical control in plants
- 9.3(i) Plant growth substances
- CP14 Core practical: gibberellin and amylase production
- 9.3(ii) Effects of auxin
- 9.3(iii) Interaction of plant growth substances
- 9.3(iv) Phytochrome, flowering and photomorphogenesis
- 9.4 Structure and function of the mammalian nervous system
- 9.4(i) Central and peripheral nervous systems
- 9.4(ii) Structure of the spinal cord
- 9.4(iii) Brain regions and their functions
- 9.4(iv) Autonomic and voluntary nervous systems
- 9.4(v) Sympathetic and parasympathetic systems
- 9.5 Nervous transmission
- 9.5(i) The resting potential
- 9.5(ii) Formation and propagation of action potentials
- 9.5(iii) Myelination and saltatory conduction
- 9.5(iv) Structure and function of synapses
- 9.5(v) Excitatory and inhibitory postsynaptic potentials
- 9.6 Effects of drugs on the nervous system
- 9.6(i) Drugs affecting synaptic transmission
- 9.7 Detection of light by mammals
- 9.7(i) Structure of the human retina
- 9.7(ii) Rhodopsin and action potentials
- 9.7(iii) Rods and cones in different light intensities
- 9.8 Control of heart rate in mammals
- 9.8(i) Autonomic control of heart rate
- 9.8(ii) Adrenaline and heart rate
- 9.9 Osmoregulation and temperature regulation
- 9.9(i) Structure of the mammalian kidney
- 9.9(ii) Urea production and ultrafiltration
- 9.9(iii) Selective reabsorption and the loop of Henle
- 9.9(iv) ADH and control of plasma concentration
- 9.9(v) Kidney adaptations of the kangaroo rat
- 9.9(vi) Endotherms and ectotherms
- 9.9(vii) Temperature regulation in endotherms
10 Ecosystems
- 10.1 The nature of ecosystems
- 10.1(i) Ecosystems and their sizes
- 10.1(ii) Trophic levels
- 10.1(iii) Ecological pyramids and transfers between trophic levels
- 10.1(iv) Techniques for assessing abundance and distribution
- 10.1(v) Choosing ecological techniques
- CP15 Core practical: sampling methods and population estimates
- 10.1(vi) Statistical tests: t-test and Spearman's rank
- 10.2 Energy transfer through ecosystems
- 10.2(i) Gross and net primary productivity
- 10.2(ii) Efficiency of energy transfer between trophic levels
- 10.2(iii) Microorganisms in nutrient recycling
- 10.3 Changes in ecosystems
- 10.3(i) Colonisation, succession and climax communities
- 10.3(ii) Biotic and abiotic factors affecting population size
- CP16 Core practical: an abiotic factor and species distribution
- 10.4 Human effects on ecosystems
- 10.4(i) Human influences on ecosystems
- 10.4(ii) CITES and global biodiversity
- 10.4(iii) Sustainability: human needs versus conservation
- 10.4(iv) Scientific community validating climate change evidence