Explore structured biology courses, solved problems, simulations and Python activities.
What biodiversity is and how it is counted. The three levels, the number of species on the Earth, the rise of diversity towards the tropics, and the species-area line, which Python fits to a table of model data.
How fast species are disappearing, and why. The mass extinctions, the four causes that ecologists call the evil quartet, and the reasons that biodiversity is worth keeping, from medicines to the right of every species to live.
How we protect what is left. Hotspots, sacred groves, national parks, sanctuaries and biosphere reserves, zoos, seed banks and cryopreservation, the Red Data Book and its categories, and the international agreements.
What a pond, a forest and a field have in common. You meet the living and the non-living parts of an ecosystem and the layers of a forest. Then you follow the grazing and the detritus food chains, join them into a food web, and find the trophic level of each organism.
How much living matter does a hectare of grass make in a year, and what becomes of it when it dies? Gross and net primary productivity, secondary productivity, what limits them, and the five steps by which dead matter is broken down into humus and minerals. Python follows the numbers.
The Sun gives a field a great deal of energy, and the hawk at the end of the chain gets very little of it. You follow the energy from sunlight to the top consumer, use the ten per cent idea, and draw the pyramids of number, biomass and energy. Then you put the whole chapter together in one energy budget.
Why farmers and scientists turn to genetically modified crops, and what they have gained. How the toxin of a soil bacterium protects cotton from its bollworms, and how a plant can silence the genes of a root worm with RNA interference. It covers the unit of the Indian syllabus (NCERT, NEET) and the matching topic of A-Level, IB and AP.
How bacteria were taught to make human insulin, how a faulty gene can be repaired in a patient, and how a tiny amount of a germ can be found early. Then the animals that carry a foreign gene, and what they are used for. It covers the unit of the Indian syllabus (NCERT, NEET) and the matching topic of A-Level, IB and AP.
Who decides whether a genetically modified organism may be released, and what happens when a company patents something that farmers have used for centuries. The lessons end with a revision of the whole chapter, with the pairs of organism, product and use that are mixed up most often. It covers the unit of the Indian syllabus (NCERT, NEET) and the matching topic of A-Level, IB and AP.
Two enzymes and one small circle of DNA are enough to move a gene from one organism to another. You learn what biotechnology is and what its two core techniques do. Then you meet the restriction enzymes that cut DNA at a palindrome, the ligases that join it again, and the vectors and hosts that carry and copy it. It serves the Indian syllabus (NCERT, NEET) and the matching topic of A-Level, IB and AP.
A gene is a few thousand letters inside a genome of millions. How do you find it, copy it and put it into a cell? You follow the steps in order. You isolate the DNA, cut it and read the pattern on a gel. You copy one gene a billion times by PCR. Then you join the gene to a vector, put it into a host and pick out the cells that took it. It serves the Indian syllabus (NCERT, NEET) and the matching topic of A-Level, IB and AP.
A recombinant cell on a plate is only the beginning. To sell a medicine, you need litres and litres of it. You see how the foreign gene is expressed and how a culture grows, how a bioreactor keeps thousands of litres of cells alive, and how the product is separated, purified and tested. Then you put the whole chapter in order and learn its usual traps. It serves the Indian syllabus (NCERT, NEET) and the matching topic of A-Level, IB and AP.
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A bare rock becomes a forest, a carbon atom goes round the world and comes back, and a phosphorus atom takes millions of years to do the same. You follow ecological succession stage by stage. You build box models of the carbon and phosphorus cycles in Python and count the services that ecosystems give us. Then you work out full energy budgets with the efficiencies that A-Level and IB use. It goes beyond the textbook, to the level of A-Level Biology, IB Higher Level and the Olympiad. Twelve harder problems and a full timed mock exam.
Before a student cuts any DNA, a plan is made on paper. You choose the enzymes from a restriction map, so that the gene goes into the vector in the right direction. You read gels and colony plates, with the controls that tell you whether to trust them. You design primers, and you learn what an expression vector must hold. It goes beyond the textbook, to the level of A-Level Biology, IB Higher Level and the Olympiad.
Beyond the textbook: how a labelled-nitrogen experiment is designed and what each model of replication predicts. How to reason about every mutant of the lac operon, how a change of one base changes a codon, and how to read a gel and count copies in PCR. Twelve harder problems and a full timed paper, at the level of A-Level Biology, IB Higher Level and the Olympiad.
Some crosses give ratios that Mendel's two laws do not predict at first sight, and some data need a test before you trust a ratio. You work out gene interaction, such as epistasis and complementary genes, by listing every cross in Python. You test ratios with chi-square, use the Hardy-Weinberg tool to find carriers, and build gene maps from three-point crosses. It goes beyond the textbook, to the level of A-Level Biology, IB Higher Level and the Olympiad.
Beyond the textbook: reading spirometer graphs of healthy and diseased lungs, working out ventilation and dead space, calculating partial pressures and the oxygen carried by blood, and reasoning about every shift of the dissociation curve. Twelve harder problems and a full timed mock exam.
Beyond the textbook: a full account of the ATP, NADPH, carbon and photons that photosynthesis spends, a point-by-point comparison of the C3 and C4 pathways, and the reading of limiting-factor graphs and classic experiments. Twelve harder problems and a full timed mock exam.