A PLACE TO GROW YOUR KNOWLEDGE

Biology,
made clear.

Understand living systems, one clear concept at a time. Explore biology and botany notes, practise with explained questions, and build your laboratory skills.

From the whole organism to the living cell.
Compound optical microscope with objective lenses, a specimen stage and focus controlsA CLOSER LOOK AT LIFE
Small details. Big discoveries.Microscope photograph · Aliva Sahoo · CC BY-SA 4.0 · displayed cropped
PUT YOUR KNOWLEDGE TO WORK

Biology paper generators

Create biology practice papers by class and chapter. Check each generated question against your prescribed textbook before using it for revision or teaching.

Matric Biology Paper Generator

Create Class 9 and 10 chapter tests with MCQs, short and long questions, adjustable marks and Word/PDF export.

Open Class 9 & 10 generator →

FSc Biology Paper Generator

Build editable Class 11 and 12 practice papers. Review the generated questions, marking guidance and curriculum coverage before use.

Open Class 11 & 12 generator →
CHAPTER-WISE BIOLOGY NOTES

Choose your chapter

Click a chapter name to reveal its published topics here, then choose a topic to read. New notes are added as each chapter grows.

Class 11 Biology

  • 1. Biodiversity and Classification
  • 2. Bacteria and Viruses

    Open this chapter to see available topics.

  • 3. Cells and Subcellular Organelles

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  • 4. Molecular Biology

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  • 5. Enzymes

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  • 6. Bioenergetics

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  • 7. Structural and Computational Biology

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  • 8. Plant Physiology

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  • 9. Human Digestive System

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  • 10. Human Respiratory System

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  • 11. Human Circulatory System
  • 12. Human Skeletal and Muscular System

    Open this chapter to see available topics.

Class 12 Biology

  • 13. Thermoregulation and Osmoregulation
  • 14. Human Urinary System

    Open this chapter to see available topics.

  • 15. Human Nervous System

    Open this chapter to see available topics.

  • 16. Human Endocrine System

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  • 17. Human Reproductive System

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  • 18. Inheritance

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  • 19. Chromosome and DNA
  • 20. Biotechnology

    Open this chapter to see available topics.

  • 21. Immunity

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  • 22. Biostatistics

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  • 23. Pharmacology

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  • 24. Evolution

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  • 25. Ecology

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MDCAT Biology

  • 1. Acellular Life

    Open this chapter to see available topics.

  • 2. Bioenergetics

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  • 3. Biological Molecules

    Open this chapter to see available topics.

  • 4. Cell Structure and Function

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  • 5. Coordination and Control - Nervous and Chemical Coordination

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  • 6. Enzymes

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  • 7. Evolution

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  • 8. Reproduction

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  • 9. Support and Movement

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  • 10. Inheritance

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  • 11. Circulation
  • 12. Immunity

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  • 13. Respiration

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  • 14. Digestion

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  • 15. Homeostasis
  • 16. Biotechnology

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Official textbooks and MDCAT syllabus

PECTAA textbook directory · PMDC MDCAT curriculum · UHS notices

Use the textbook edition prescribed by your college. MDCAT units follow their own curriculum and numbering.

ABOUT THESE RESOURCES

How to study with PreachBio

Choose a class or MDCAT chapter above to see its published lessons. Read the explanation, work through the examples, then test yourself with the questions. Notes are study aids; use your current textbook and official syllabus for exam requirements.

PreachBio is an independent biology and botany resource. Some material was drafted or structured with AI assistance, and older pages are under ongoing review. If you spot an error or broken link, send the page URL and a correction so it can be checked.

BUILD YOUR UNDERSTANDING

Explore biology concepts

Start with a worked lesson, then check your understanding with explained questions and a separate practice quiz.

What are you curious about?

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YOUR NEXT DISCOVERY

Explore by topic

Choose a subject. Start with the concepts.
Keep building from there.

EXPLORE THE COLLECTIONS

All biology and botany courses

Browse our course and practice collections, including subjects with a small number of lessons. These are growing collections; coverage varies by subject.

School-board collections and university courses have different levels. Use the study-level guides above to choose a starting point.
PUT KNOWLEDGE INTO PRACTICE

A good place to start

KEEP EXPLORING

Latest study notes

More explanations, revision topics and practical resources.

Population Interactions in Plant Ecology: 7 Types, Examples & Quiz
Ginkgo biloba Reproduction: Pollen, Ovules & Motile Sperm | BOT-509
Viruses: Structure & Classification | MDCAT Acellular Life 1.1, NEET & MCAT