The human heart
Follow blood through chambers, valves and the lungs.
Read lesson →BIOLOGY, CONNECTED.
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Cell Biology
Cells, membranes, organelles and cell division.
Explore topic ↗02Genetics
Inheritance, variation and interpreting genetic crosses.
Explore topic ↗03Human Biology
Circulation, homeostasis and the immune system.
Explore topic ↗04Plant Biology
Plant structures, transport, growth and reproduction.
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Populations, interactions and biodiversity.
Explore topic ↗06Biochemistry
Biomolecules, enzymes and metabolic pathways.
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Bacteria, viruses and microbial calculations.
Explore topic ↗08Evolution
Variation, selection and changes in populations.
Explore topic ↗09Molecular Biology
DNA, RNA, gene expression and repair.
Explore topic ↗Featured learning resources
Transcription & mRNA
Connect a DNA template to a processed RNA message.
Read lesson →Enzyme inhibition
Make sense of Km, Vmax and inhibition models.
Read lesson →Mitosis in practice
Calculate mitotic index from a root-tip sample.
Read lesson →Ecological interactions
Compare the ways organisms affect each other.
Read lesson →The pentose phosphate pathway
Follow the production of NADPH in plant cells.
Read lesson →How PreachBio helps you learn
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Learn
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Understand
Connect diagrams and worked examples.
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Try questions before reading answers.
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Master
Explain a process in a new context.
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MCQ practice
Use enzyme-inhibition questions to distinguish changes in Km from changes in Vmax.
Try this lesson →Topic quizzes
Revise the cell cycle and test your interpretation of a dividing-cell sample.
Try this lesson →Application questions
Explain a feedback response using receptors, a control centre and effectors.
Try this lesson →Data interpretation
Calculate and compare biodiversity with the assumptions made explicit.
Try this lesson →Flash review
Sketch DNA → RNA → protein, then explain what happens during transcription.
Try this lesson →Biology study tools
Formula guides and worked examples for your next practical or revision session.
Mitotic index
Count dividing cells and interpret a sample.
Open study resource →Chromatography
Calculate Rf and compare pigment separation.
Open study resource →Stomatal measurements
Distinguish density from stomatal index.
Open study resource →Advanced Botany Courses
Explore university-level resources in plant biochemistry, ecology, taxonomy, physiology and advanced botanical topics. Coverage varies by collection.
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Read the explanation, follow the evidence and test your reasoning. PreachBio is an independent biology and botany resource; some material was drafted or structured with AI assistance, and older pages are under ongoing review.
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