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Chapter-by-chapter notes written straight from the curriculum. Read free, then practise the same chapter with an AI-generated quiz.
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Learn the key terms of genetics, understand Mendel's laws of dominance, segregation and independent assortment, and work out monohybrid and dihybrid crosses step by step with Punnett squares and ratios.
Read articleLearn what fertilisation, implantation, gestation and parturition mean, how the placenta forms and supplies the embryo, what hormones it makes, why amniotic fluid matters, and how identical and fraternal twins arise.
Read articleFollow the menstrual cycle phase by phase and find when ovulation happens, learn what oestrogen and progesterone do in the cycle and in pregnancy, see the roles of testosterone and prolactin, and understand menarche and menopause.
Read articleLearn the organs and accessory glands of the male reproductive system, the organs of the female reproductive system, how the structure of a sperm and an ovum suits each one's job, and the changes that appear in boys and girls at puberty.
Read articleLearn the hormones of the adrenal cortex, why adrenaline is called the emergency hormone, what growth hormone, tropic hormones, ADH and oxytocin do, and how too little or too much of them upsets the body, plus the feedback loop that controls TSH.
Read articleTell endocrine glands from exocrine glands and learn what a hormone is, locate the pancreas, thyroid, adrenal and pituitary glands, and see what insulin, glucagon and thyroxine do and what happens when there is too little or too much.
Read articleLearn the parts of the external, middle and inner ear, follow a sound from the pinna to the auditory nerve, and see how the semicircular canals and vestibule keep your body balanced.
Read articleLearn the parts of the human eye and what each does, how the eye focuses near and far and adjusts to light, why two eyes judge depth, and what causes and corrects myopia, hypermetropia, presbyopia, astigmatism and cataract.
Read articleLearn what each major part of the brain does, how the spinal cord is built and why its grey matter lies inside, follow a reflex arc from receptor to effector, and tell voluntary, involuntary and reflex actions apart.
Read articleLearn the parts of a neuron and its three types, what nerves and synapses are and how an impulse crosses the gap, how the nervous system is organised, and how the sympathetic and parasympathetic systems pull the body in opposite directions.
Read articleFollow blood through ultrafiltration, selective reabsorption and tubular secretion, learn what normal urine contains and what abnormal substances signal, see why urine changes with the seasons and in cholera, and understand gout, kidney stones and dialysis.
Read articleFind out which organs remove which wastes, how the urinary system is arranged, what a kidney looks like inside, how blood flows through it, and how each part of a nephron does its own job.
Read articleCompare arteries, veins and capillaries and see how each wall suits its job, name the blood vessels that enter and leave the liver, kidneys and lungs, follow plasma as it leaks out to form tissue fluid and drains away as lymph, and learn what the spleen and tonsils do.
Read articleLearn the outside and inside of the human heart and the vessels that enter and leave it, follow systole and diastole through one heartbeat and the SA node that starts it, trace blood through the pulmonary and systemic circuits, and understand pulse, blood pressure and the hepatic portal system.
Read articleLearn what blood is made of and how red cells, white cells and platelets differ, see why losing a nucleus makes red blood cells better oxygen carriers, name the disorders of too few or too many blood cells, and understand clotting, ABO blood groups and the Rh factor.
Read articleFollow oxygen and carbon dioxide as blood carries them between the lungs and the tissues, separate breathing from tissue respiration and see where body heat comes from, compare anaerobic respiration in yeast and in human muscles, and understand breathlessness at high altitude, hypoxia and asphyxiation.
Read articleFollow air from the nostrils to the alveoli, see how the diaphragm and intercostal muscles change the size of the chest to draw air in and push it out, understand why alveoli are so good at gas exchange, and work out tidal volume, vital capacity and residual volume.
Read articleLearn what plant growth regulators are and what auxins, gibberellins, cytokinins, abscisic acid and ethylene each do, understand phototropism, geotropism, hydrotropism, thigmotropism and chemotropism with everyday examples, and see how a clinostat proves that gravity steers roots and shoots.
Read articleWork through the experiments that prove light, carbon dioxide and chlorophyll are needed for photosynthesis, learn why leaves are destarched and how the starch test works, collect oxygen from Hydrilla, see how leaves are built for photosynthesis, and follow carbon around the living world.
Read articleWrite the balanced equation for photosynthesis and see why all life depends on it, learn the structure of a chloroplast and where each stage happens, follow the light reaction from chlorophyll to oxygen, ATP and NADPH, and see how the dark reaction builds glucose from carbon dioxide.
Read articleSee how light, temperature, humidity and wind speed up or slow down transpiration, learn how Ganong's potometer measures water uptake and where it falls short, work through the weight-loss and cobalt chloride experiments, and tell transpiration apart from guttation and bleeding.
Read articleLearn what transpiration is and how stomatal, cuticular and lenticular transpiration differ, why losing water actually helps a plant, how potassium ions make guard cells open and close the stomata, and how desert and dry-region plants cut their water loss.
Read articleSee how a single root hair is built to absorb water, why roots take in water passively but minerals largely by active transport, how root pressure, cohesion, adhesion and transpiration pull lift sap up the xylem, and which simple experiments prove that roots absorb water and xylem conducts it.
Read articleTell diffusion, osmosis and imbibition apart, understand semi-permeable and selectively permeable membranes, predict what hypotonic, hypertonic and isotonic solutions do to a plant cell, and explain turgidity, plasmolysis and deplasmolysis with the thistle funnel and potato osmoscope experiments.
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