Explore structured biology courses, solved problems, simulations and Python activities.
How does one cell become two? A cell grows, copies its DNA and then divides. You meet the phases of the cell cycle and count the DNA and the chromosomes at each stage. Then you follow mitosis and cytokinesis in animal and plant cells and see what mitosis does for a body. It serves the Indian syllabus (NCERT, NEET) and the matching topic of A-Level, IB and AP.
How does a cell halve its chromosome number and make four different cells? You meet the five stages of prophase I, synapsis and crossing over, and the two divisions of meiosis. Then you compare meiosis with mitosis and see why it keeps the chromosome number steady and makes variation. It serves the Indian syllabus (NCERT, NEET) and the matching topic of A-Level, IB and AP.
What keeps the cell cycle in order, and what happens when it fails? You meet the checkpoints, the cyclins and the kinases they switch on, and the changes that lead to cancer. Then you do the sums of the topic: chromosomes, chromatids and DNA at every stage, DNA graphs, the mitotic index and the number of cells after many divisions. It serves the Indian syllabus (NCERT, NEET) and the matching topic of A-Level, IB and AP.
What blood is made of and what each kind of cell does. Why the blood group matters in a transfusion, and what the Rh factor means for a baby. How a clot forms, and how the lymph returns tissue fluid to the blood.
How animals move their blood: open and closed circulation, and the hearts of fish, frogs and mammals. The chambers, valves and nodal tissue of the human heart, and the two loops of the double circulation.
What the heart does in one beat, and how much blood it pumps in a minute. How the electrical signal of the heart is drawn as an ECG, how nerves and hormones change the heart rate, and what goes wrong in high blood pressure and heart disease.
How do a sponge, an earthworm, a fish and a human breathe? Here you learn the parts of the human respiratory system, the movements of the chest that pull air in and push it out, and the volumes of air that a spirometer measures.
Why does oxygen move into the blood and carbon dioxide move out? You learn about partial pressure, the thin membrane of the alveolus, the part that haemoglobin plays in carrying oxygen, and how to read the oxygen dissociation curve.
How does carbon dioxide travel back from the tissues? You follow the bicarbonate pathway and the chloride shift. You find the centres in the brain that set the rhythm of breathing. You also learn what goes wrong in asthma, emphysema and the dust diseases of workers.
How a plant grows and how fast. The three phases of growth, arithmetic and geometric growth, absolute and relative growth rate, and the conditions growth needs. Then differentiation, dedifferentiation, redifferentiation, development and plasticity.
The five chemical messengers of a plant: auxins, gibberellins, cytokinins, ethylene and abscisic acid. What each one does, the experiments that found them, and how they work together.
Why a seed can wait for years, how a plant knows the length of the night, and why some plants need a cold winter before they flower. With the classic experiments and how to read them.
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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.
Beyond the textbook: how proteins fold and why shape means function, and Michaelis-Menten kinetics with the Lineweaver-Burk plot. Then competitive and non-competitive inhibition by numbers, and how pathways are controlled by feedback, with a full timed paper.
The plant groups side by side, with their key examples, economic uses and the tricky points that exams test, worked step by step, and a full NEET-style mock exam.
Two kinds of bacteria can differ from each other as much as a bacterium differs from you. How do biologists know? In this course we read three ideas that the main chapter only touches: the three domains of life, how bacteria are stained, grown and counted in a laboratory, and how a virus takes over a cell. Then we solve harder problems at the level of NEET, AP Biology and A-Level Biology, and take a timed test.
A horse and a donkey can have a young one, the mule, and the mule cannot have young. So are the horse and the donkey one species or two? In this course we read three ideas that the main chapter only touches: what a species really is, the finer rules that give each species one name, and how a key and a DNA barcode find a name. Then we solve harder problems at the level of NEET, AP Biology and A-Level Biology, and take a timed test.