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Explain and predict periodic trends in atomic and ionic radii, ionisation enthalpy, electron gain enthalpy and electronegativity, and relate each trend to electronic configuration, shielding and effective nuclear charge.
Read articleFollow how periodic classification developed from triads and octaves through Mendeleev's periodic law to the modern periodic law, see how Moseley's relation links X-rays to atomic number, and learn the periods, groups and blocks of the modern periodic table.
Read articleAssign the four quantum numbers to an electron, understand the shapes and nodes of s, p and d orbitals, and apply the Aufbau principle, Pauli's exclusion principle and Hund's rule to write electronic configurations of atoms and ions.
Read articleUnderstand Bohr's model of the hydrogen atom with calculations of orbit energies and radii, the dual nature of matter and radiation through de Broglie's equation, and Heisenberg's uncertainty principle and why it replaces orbits with orbitals.
Read articleLearn the experimental evidence for electrons, protons and neutrons, Thomson's and Rutherford's atomic models with the alpha-particle scattering experiment, and the meaning of atomic number, mass number, isotopes and isobars.
Read articleSolve limiting reagent and percentage yield problems, calculate and interconvert molarity, molality, normality and mole fraction, and carry out dilution and titration calculations.
Read articleMaster the mole concept and Avogadro's number to convert between mass, moles and particles, calculate percentage composition from a formula, and work out empirical and molecular formulas from composition data.
Read articleLearn the laws of chemical combination — conservation of mass, definite proportions, multiple proportions, gaseous volumes and Avogadro's law — the postulates of Dalton's atomic theory, and the difference between atomic, molecular and formula mass.
Read articleUnderstand what biodiversity is and how it is distributed, why species are being lost with examples of recent extinctions, how in-situ and ex-situ conservation work, and why hotspots, the Red Data Book, Ramsar sites and international conventions matter.
Read articleUnderstand the structure and function of a pond ecosystem, gross and net primary productivity, decomposition and its controlling factors, energy flow through food chains, food webs and trophic levels, and pyramids of number, biomass and energy.
Read articleLearn population attributes such as birth rate, death rate, sex ratio and age pyramids, how population density is measured, the exponential and logistic growth models with their equations and graphs, and interactions such as mutualism, competition, predation, parasitism, commensalism and amensalism.
Read articleExplore how biotechnology produces Bt crops, pest-resistant plants through RNA interference and vitamin-rich golden rice, human insulin, gene therapy and molecular diagnosis, and transgenic animals, along with biosafety, biopiracy and biopatents.
Read articleLearn what biotechnology is and how DNA and a gene of interest are isolated, how recombinant DNA is made with restriction enzymes and ligase, how cloning vectors and gene transfer work, and how recombinants are selected, amplified by PCR and produced in bioreactors.
Read articleDiscover how microbes make curd, bread, cheese, beverages, antibiotics, organic acids and enzymes, how they treat sewage and produce biogas, and how they act as biocontrol agents and biofertilisers in integrated pest management.
Read articleUnderstand innate and acquired immunity with humoral and cell-mediated responses, the structure and classes of antibodies, the cause, spread, diagnosis and prevention of AIDS, and the effects of alcohol, smoking and drugs of abuse with ways to prevent misuse.
Read articleLearn the causes, spread, symptoms and prevention of common viral, bacterial and protozoal diseases, the life cycle of Plasmodium, ascariasis and filariasis, and the types, features, diagnosis and treatment of cancer.
Read articleLearn the main ideas of Darwinism with examples of natural selection, Neo-Darwinism and the Hardy-Weinberg principle with simple calculations, and the stages of human evolution from Dryopithecus to modern humans.
Read articleUnderstand the Oparin-Haldane theory of the origin of life and the Miller-Urey experiment, the morphological, embryological, fossil and molecular evidence for evolution, homologous and analogous organs, and adaptive radiation in Darwin's finches.
Read articleFollow transcription and RNA processing in eukaryotes, the features of the genetic code and translation in bacteria, gene regulation through the lac operon, and the goals of the Human Genome Project and DNA fingerprinting.
Read articleLearn the properties a genetic material must have and the experiments showing DNA is the genetic material, the double-helix structure of DNA and how it is packed into eukaryotic chromosomes, and how semi-conservative replication works with DNA polymerase and ligase.
Read articleClassify mutations as spontaneous or induced and understand point mutations, then study Mendelian disorders such as haemophilia, sickle-cell anaemia, phenylketonuria and thalassaemia, and chromosomal disorders such as Down, Klinefelter and Turner syndromes.
Read articleExplore incomplete dominance, co-dominance and multiple alleles, polygenic inheritance, pleiotropy and pedigree charts, the chromosomal theory and sex determination in humans, birds, honeybees and grasshoppers, and sex-linked inheritance, linkage and crossing over.
Read articleLearn Mendel's laws of dominance, segregation and independent assortment and why the pea experiments worked, solve monohybrid and dihybrid crosses with Punnett squares, tell a back cross from a test cross, and master the basic terms of genetics.
Read articleUnderstand why reproductive health matters and the national programmes that promote it, how methods of contraception work, what medical termination of pregnancy, amniocentesis and assisted reproductive technologies are, and how sexually transmitted diseases can be prevented.
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