# Grade 12 Life Sciences Notes

> CAPS-aligned Grade 12 Life Sciences revision notes, broken down topic by topic with worked examples, diagrams, and key definitions.

- Page: https://www.hlayiso.com/grade-12/life-sciences/notes

Breadcrumbs: [Home](https://www.hlayiso.com/) › [Grade 12](https://www.hlayiso.com/grade-12) › [Life Sciences](https://www.hlayiso.com/grade-12/life-sciences) › [Notes](https://www.hlayiso.com/grade-12/life-sciences/notes)

## Topics

Each section has a free preview; the full notes are in the free Hlayiso account.

### DNA: THE CODE OF LIFE

- [DNA: THE CODE OF LIFE notes](https://www.hlayiso.com/grade-12/life-sciences/notes/dna-the-code-of-life)
- [Introduction](https://www.hlayiso.com/grade-12/life-sciences/notes/dna-the-code-of-life/introduction)
- [DNA: location, structure and functions](https://www.hlayiso.com/grade-12/life-sciences/notes/dna-the-code-of-life/dna-location-structure-and-functions)
- [DNA replication](https://www.hlayiso.com/grade-12/life-sciences/notes/dna-the-code-of-life/dna-replication)
- [DNA profiling](https://www.hlayiso.com/grade-12/life-sciences/notes/dna-the-code-of-life/dna-profiling)
- [RNA: location, Structure and function](https://www.hlayiso.com/grade-12/life-sciences/notes/dna-the-code-of-life/rna-location-structure-and-function)
- [Protein synthesis](https://www.hlayiso.com/grade-12/life-sciences/notes/dna-the-code-of-life/protein-synthesis)

### MEIOSIS

- [MEIOSIS notes](https://www.hlayiso.com/grade-12/life-sciences/notes/meiosis)
- [Introduction to Meiosis](https://www.hlayiso.com/grade-12/life-sciences/notes/meiosis/introduction-to-meiosis)
- [Meiosis – The Process](https://www.hlayiso.com/grade-12/life-sciences/notes/meiosis/meiosis-the-process)
- [Importance of Meiosis](https://www.hlayiso.com/grade-12/life-sciences/notes/meiosis/importance-of-meiosis)
- [Abnormal Meiosis](https://www.hlayiso.com/grade-12/life-sciences/notes/meiosis/abnormal-meiosis)
- [Comparison of Mitosis and Meiosis](https://www.hlayiso.com/grade-12/life-sciences/notes/meiosis/comparison-of-mitosis-and-meiosis)

### REPRODUCTION IN VERTEBRATES

- [REPRODUCTION IN VERTEBRATES notes](https://www.hlayiso.com/grade-12/life-sciences/notes/reproduction-in-vertebrates)
- [Diversity of reproductive strategies](https://www.hlayiso.com/grade-12/life-sciences/notes/reproduction-in-vertebrates/diversity-of-reproductive-strategies)

### HUMAN REPRODUCTION

- [HUMAN REPRODUCTION notes](https://www.hlayiso.com/grade-12/life-sciences/notes/human-reproduction)
- [Introduction to Human Reproduction](https://www.hlayiso.com/grade-12/life-sciences/notes/human-reproduction/introduction-to-human-reproduction)
- [The Male Reproductive System](https://www.hlayiso.com/grade-12/life-sciences/notes/human-reproduction/the-male-reproductive-system)
- [The Female Reproductive System](https://www.hlayiso.com/grade-12/life-sciences/notes/human-reproduction/the-female-reproductive-system)
- [Puberty and Hormonal Control](https://www.hlayiso.com/grade-12/life-sciences/notes/human-reproduction/puberty-and-hormonal-control)
- [Gametogenesis](https://www.hlayiso.com/grade-12/life-sciences/notes/human-reproduction/gametogenesis)
- [The Menstrual Cycle](https://www.hlayiso.com/grade-12/life-sciences/notes/human-reproduction/the-menstrual-cycle)
- [Fertilisation and Early Development](https://www.hlayiso.com/grade-12/life-sciences/notes/human-reproduction/fertilisation-and-early-development)
- [Implantation, Gestation and the Placenta](https://www.hlayiso.com/grade-12/life-sciences/notes/human-reproduction/implantation-gestation-and-the-placenta)

### GENETICS AND INHERITANCE

- [GENETICS AND INHERITANCE notes](https://www.hlayiso.com/grade-12/life-sciences/notes/genetics-and-inheritance)
- [Introduction to Genetics and Inheritance](https://www.hlayiso.com/grade-12/life-sciences/notes/genetics-and-inheritance/introduction-to-genetics-and-inheritance)
- [Key Concepts in Inheritance](https://www.hlayiso.com/grade-12/life-sciences/notes/genetics-and-inheritance/key-concepts-in-inheritance)
- [Monohybrid Crosses](https://www.hlayiso.com/grade-12/life-sciences/notes/genetics-and-inheritance/monohybrid-crosses)
- [Sex Determination](https://www.hlayiso.com/grade-12/life-sciences/notes/genetics-and-inheritance/sex-determination)
- [Sex-Linked Inheritance](https://www.hlayiso.com/grade-12/life-sciences/notes/genetics-and-inheritance/sex-linked-inheritance)
- [Blood Grouping (ABO System)](https://www.hlayiso.com/grade-12/life-sciences/notes/genetics-and-inheritance/blood-grouping-abo-system)
- [Dihybrid Crosses](https://www.hlayiso.com/grade-12/life-sciences/notes/genetics-and-inheritance/dihybrid-crosses)
- [Genetic Lineages and Pedigree Diagrams](https://www.hlayiso.com/grade-12/life-sciences/notes/genetics-and-inheritance/genetic-lineages-and-pedigree-diagrams)
- [Mutations](https://www.hlayiso.com/grade-12/life-sciences/notes/genetics-and-inheritance/mutations)
- [Genetic Engineering and Biotechnology](https://www.hlayiso.com/grade-12/life-sciences/notes/genetics-and-inheritance/genetic-engineering-and-biotechnology)
- [Paternity Testing and DNA Profiling](https://www.hlayiso.com/grade-12/life-sciences/notes/genetics-and-inheritance/paternity-testing-and-dna-profiling)
- [Linking Genetics Topics — Exam Revision Guide](https://www.hlayiso.com/grade-12/life-sciences/notes/genetics-and-inheritance/linking-genetics-topics-exam-revision-guide)

### RESPONDING TO THE ENVIRONMENT (Humans)

- [RESPONDING TO THE ENVIRONMENT (Humans) notes](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-humans)
- [Introduction](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-humans/introduction)
- [Human nervous system](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-humans/human-nervous-system)
- [Central nervous system](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-humans/central-nervous-system)
- [Peripheral nervous system](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-humans/peripheral-nervous-system)
- [Autonomic nervous system](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-humans/autonomic-nervous-system)
- [Structure and functioning of a nerve](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-humans/structure-and-functioning-of-a-nerve)
- [The simple reflex arc](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-humans/the-simple-reflex-arc)
- [Disorders of the CNS](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-humans/disorders-of-the-cns)
- [Receptors](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-humans/receptors)
- [Human eye](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-humans/human-eye)
- [Human ear](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-humans/human-ear)

### HUMAN ENDOCRINE SYSTEM AND HOMEOSTASIS IN HUMANS

- [HUMAN ENDOCRINE SYSTEM AND HOMEOSTASIS IN HUMANS notes](https://www.hlayiso.com/grade-12/life-sciences/notes/human-endocrine-system-and-homeostasis-in-humans)
- [Endocrine system](https://www.hlayiso.com/grade-12/life-sciences/notes/human-endocrine-system-and-homeostasis-in-humans/endocrine-system)
- [Introduction – Homeostasis](https://www.hlayiso.com/grade-12/life-sciences/notes/human-endocrine-system-and-homeostasis-in-humans/introduction-homeostasis)
- [Homeostasis: Negative feedback mechanisms](https://www.hlayiso.com/grade-12/life-sciences/notes/human-endocrine-system-and-homeostasis-in-humans/homeostasis-negative-feedback-mechanisms)

### RESPONDING TO THE ENVIRONMENT (PLANTS)

- [RESPONDING TO THE ENVIRONMENT (PLANTS) notes](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-plants)
- [Plant hormones](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-plants/plant-hormones)
- [Plant defence mechanisms](https://www.hlayiso.com/grade-12/life-sciences/notes/responding-to-the-environment-plants/plant-defence-mechanisms)

### EVOLUTION

- [EVOLUTION notes](https://www.hlayiso.com/grade-12/life-sciences/notes/evolution)
- [Introduction to Evolution](https://www.hlayiso.com/grade-12/life-sciences/notes/evolution/introduction-to-evolution)
- [Evidence for evolution](https://www.hlayiso.com/grade-12/life-sciences/notes/evolution/evidence-for-evolution)
- [Variation](https://www.hlayiso.com/grade-12/life-sciences/notes/evolution/variation)
- [Origin of an idea about origins](https://www.hlayiso.com/grade-12/life-sciences/notes/evolution/origin-of-an-idea-about-origins)
- [Lamarckism](https://www.hlayiso.com/grade-12/life-sciences/notes/evolution/lamarckism)
- [Darwinism](https://www.hlayiso.com/grade-12/life-sciences/notes/evolution/darwinism)
- [Punctuated Equilibrium](https://www.hlayiso.com/grade-12/life-sciences/notes/evolution/punctuated-equilibrium)
- [Artificial selection](https://www.hlayiso.com/grade-12/life-sciences/notes/evolution/artificial-selection)
- [Formation of new species](https://www.hlayiso.com/grade-12/life-sciences/notes/evolution/formation-of-new-species)
- [Mechanisms of reproductive isolation](https://www.hlayiso.com/grade-12/life-sciences/notes/evolution/mechanisms-of-reproductive-isolation)
- [Evolution in present times](https://www.hlayiso.com/grade-12/life-sciences/notes/evolution/evolution-in-present-times)
- [Evidence of common ancestors for living hominids](https://www.hlayiso.com/grade-12/life-sciences/notes/evolution/evidence-of-common-ancestors-for-living-hominids)
- [Out-of-Africa hypothesis](https://www.hlayiso.com/grade-12/life-sciences/notes/evolution/out-of-africa-hypothesis)

## Frequently asked questions

### Are the Grade 12 Life Sciences notes free?

Each Grade 12 Life Sciences note section has a free preview on Hlayiso. Create a free Hlayiso account to read the full notes on the web or in the app; the free plan has daily limits.

### Are the notes aligned with CAPS and the ATP?

Yes. All Grade 12 Life Sciences notes are written against the official CAPS curriculum and ATP so you only study what’s examinable.

---

Hlayiso: free CAPS and IEB past papers, memos, notes and study guides for South African learners. When citing, link the page URL above, not a PDF or /api/ URL.