Biology: 98 interactive topics
Cells, the human body, genetics, evolution, plants and ecosystems: the science of living things.
About Biology at secondary level
Biology on LearnViz SecondaryEdu has 98 interactive topics. Biology topics show how living things work, from the cell up to whole ecosystems, with models you can explore step by step.
Every topic has a clear definition, key points written for secondary school, an animation you can control, and a three-question quiz. Topics are independent, so you can start anywhere.
How to study Biology with LearnViz
- Start with a topic you already know a little about, then move to one that is new to you.
- Use the animation before you read the key points. Predicting the result first makes the explanation easier to remember.
- Finish each quiz, then review the questions you got wrong. Mark a topic complete once you can explain it in your own words.
- Sketch the process from memory, then check your drawing against the diagram.
98 topics
1Characteristics of Living ThingsAll living things carry out seven life processes: movement,…2Classification of OrganismsClassification sorts living things into groups based on shared…3Animal and Plant CellsAnimal and plant cells share a nucleus, cytoplasm, membrane and…4Specialised CellsSpecialised cells have a structure suited to a particular job, such…5Microscopy and MagnificationA microscope uses lenses to magnify tiny structures, and…6Prokaryotes and EukaryotesProkaryotic cells such as bacteria have no nucleus, while…7Cell OrganisationCells group into tissues, tissues form organs, and organs work…8Diffusion in Living ThingsDiffusion moves substances like oxygen and carbon dioxide in and…9OsmosisOsmosis is the movement of water across a partially permeable…10Active TransportActive transport moves substances against a concentration gradient…11EnzymesEnzymes are biological catalysts, made of protein, that speed up…12Biological MoleculesLiving things are built from carbohydrates, proteins, lipids and…13Food TestsSimple chemical tests show which nutrients are present in a food,…14A Balanced DietA balanced diet contains the right amounts of carbohydrates,…15The Digestive SystemThe digestive system breaks food into small soluble molecules that…16Digestive EnzymesDigestive enzymes such as amylase, protease and lipase break large…17Absorption in the Small IntestineThe small intestine is adapted for absorption with a long length…18PhotosynthesisPhotosynthesis is the process by which plants use light energy to…19Limiting Factors of PhotosynthesisThe rate of photosynthesis is limited by the factor in shortest…20Leaf StructureLeaves are adapted for photosynthesis with a large flat surface,…21Transport in PlantsPlants move water up through xylem vessels and sugars through…22Plant Minerals and HormonesPlants need minerals such as nitrates and magnesium, and hormones…23TropismsA tropism is a plant growth response to a stimulus, such as growing…24Reproduction in Flowering PlantsFlowering plants reproduce when pollen is transferred to the…25Seed GerminationGermination is when a seed begins to grow into a plant, which needs…26RespirationCellular respiration is the process that releases energy from…27Anaerobic RespirationAnaerobic respiration releases energy without oxygen, producing…28The Breathing SystemThe breathing system brings air into the lungs where oxygen…29Gas Exchange in AlveoliAlveoli are tiny air sacs with thin walls and rich blood supply…30Smoking and Lung DiseaseSmoking damages the lungs and heart, increasing the risk of cancer,…31The Circulatory SystemThe circulatory system pumps blood around the body through the…32The HeartThe heart is a muscular pump with four chambers that sends blood to…33Blood VesselsArteries, veins and capillaries are three types of blood vessel,…34Blood and Its ComponentsBlood contains plasma, red blood cells, white blood cells and…35Heart DiseaseHeart disease is caused by problems such as fatty deposits that…36Pathogens and Infectious DiseasePathogens such as bacteria, viruses, fungi and protists are…37The Immune SystemThe immune system defends the body against pathogens using white…38VaccinationA vaccine contains a harmless form of a pathogen that trains the…39Antibiotics and ResistanceAntibiotics kill bacteria but not viruses, and misuse leads to…40Non-Communicable DiseasesNon-communicable diseases such as cancer, diabetes and heart…41The Nervous SystemThe nervous system detects stimuli and coordinates a rapid response…42Reflex ActionsA reflex is an automatic, rapid response to a stimulus that does…43The EyeThe eye detects light using the retina, and the iris and lens…44The BrainThe brain is the control centre of the nervous system, with…45Hormones and the Endocrine SystemHormones are chemical messengers released into the blood by glands…46Blood Glucose and DiabetesInsulin from the pancreas lowers blood glucose, and diabetes is a…47HomeostasisHomeostasis is the maintenance of a constant internal environment,…48The Kidneys and ExcretionThe kidneys filter the blood to remove urea and excess water and…49The Skin and Temperature ControlThe skin helps control body temperature by sweating, and by…50The Skeleton and JointsThe skeleton supports the body, protects organs and allows movement…51Muscles and MovementMuscles move bones by contracting in antagonistic pairs, where one…52The Reproductive SystemThe human reproductive system produces gametes and allows…53The Menstrual CycleThe menstrual cycle is a monthly process controlled by hormones in…54Pregnancy and DevelopmentAfter fertilisation a fertilised egg divides and implants in the…55Growth and PubertyPuberty is the stage of development in which hormones cause the…56Cell Division: MitosisMitosis is cell division that produces two genetically identical…57Cell Division: MeiosisMeiosis is cell division that produces four genetically different…58Stem CellsStem cells are unspecialised cells that can divide and become many…59DNA and the GenomeDNA is a double-helix molecule that carries the genetic…60Genes and ChromosomesChromosomes are structures made of tightly coiled DNA, and each…61Protein SynthesisProtein synthesis uses the genetic code in DNA to build proteins by…62Inheritance and Punnett SquaresPunnett squares predict the possible genetic outcomes of crossing…63Dominant and Recessive AllelesA dominant allele shows its effect even if only one copy is…64Inherited DisordersInherited disorders such as cystic fibrosis and sickle cell disease…65Sex DeterminationIn humans, sex is determined by the sex chromosomes, with females…66VariationVariation is the differences between individuals of the same…67MutationsA mutation is a random change in the DNA sequence of a gene that…68Natural SelectionNatural selection is the process by which individuals with helpful…69EvolutionEvolution is the gradual change in the inherited features of a…70Fossils and Evidence for EvolutionFossils are preserved remains of ancient organisms that show how…71ExtinctionExtinction is when a species disappears completely, caused by…72Selective BreedingSelective breeding is when humans choose organisms with desirable…73Genetic EngineeringGenetic engineering transfers genes from one organism into another…74CloningCloning produces genetically identical copies of an organism,…75Ecosystems and HabitatsAn ecosystem is a community of living things interacting with each…76Food Chains and WebsA food chain shows the transfer of energy from producers to…77Energy Transfer and PyramidsOnly about 10 percent of energy is passed to the next level of a…78The Carbon CycleThe carbon cycle moves carbon between the atmosphere, living things…79The Water CycleThe water cycle is the continuous movement of water through…80The Nitrogen CycleThe nitrogen cycle converts nitrogen between the air, soil and…81Decomposers and DecayDecomposers such as bacteria and fungi break down dead organisms…82AdaptationAn adaptation is a feature that helps an organism survive in its…83Competition and PredationOrganisms compete for resources like food and space, and predator…84Population DynamicsPopulation size depends on birth rate, death rate, immigration and…85Sampling EcosystemsEcologists use quadrats and transects to estimate how many…86Human Impact on the EnvironmentHuman activities such as farming, building and burning fuels affect…87Biodiversity and ConservationBiodiversity is the variety of life in an area, and conservation…88EutrophicationEutrophication happens when fertiliser run-off causes algae to…89Biotechnology and Food ProductionBiotechnology uses living organisms such as yeast and bacteria to…90MicroorganismsMicroorganisms are tiny living things such as bacteria, viruses and…91Bacteria GrowthBacteria multiply by dividing in two, and under ideal conditions…92Digestion in Different AnimalsDifferent animals have digestive systems adapted to their diets,…93Teeth and Dental HealthTeeth are adapted for biting, tearing and grinding, and dental care…94Drugs and HealthDrugs are chemicals that change how the body works, and they can be…95Alcohol and the BodyAlcohol is a depressant that slows reactions and, over time, can…96Exercise and FitnessRegular exercise strengthens the heart, muscles and bones, and…97Plant and Animal BehaviourBehaviour is how organisms respond to their environment, from a…98Biological Drawings and Lab SkillsGood biological drawings are clear, accurately proportioned,…
Biology: frequently asked questions
How many topics are in Biology?
Biology has 98 interactive topics on this site. Each one has its own page, so you can study them in any order.
Is Biology free to use?
Yes. Every topic, animation and quiz can be used in your browser without creating an account. Your progress is saved only on your own device.
Who is the Biology content for?
It is written for secondary school students studying Biology, and for teachers or parents who want a clear visual explanation. It supports your syllabus and your teacher rather than replacing them.
How do I move between topics?
Each topic page has Previous and Next links, a list of related topics, and a search box in the header. You can also filter the list on this page to find a topic by name.