Unit Overview
Biodiversity, Classification, Conservation and Genetic Technology
CIE A-Level BiologyΒ· 5 min read π n/a
1. Unit at a Glance
This unit follows a logical arc from measuring the variety of life on Earth, to how we organize and name that diversity, to how we protect threatened species and ecosystems, and finally to how modern genetic technology lets us manipulate DNA for a wide range of human benefits.
Each sub-topic builds on the previous one: understanding biodiversity sets the context for why classification matters, why conservation is a critical global priority, and how genetic technology can advance both conservation goals and biotechnological progress.
This unit is split into 7 core sub-topics:
Biodiversity and measurement
Introduces levels of biodiversity and methods to calculate species richness and diversity.
β β β± 10 min
Classification
Covers traditional and modern classification systems, including the three-domain model.
β β β± 8 min
Conservation of endangered species
Explores threats to biodiversity and compares in-situ and ex-situ conservation strategies.
β β β β± 12 min
Principles of gene technology
Outlines core techniques including PCR, gel electrophoresis, restriction enzymes and gene cloning.
β β β β β± 15 min
Genetic modification
Explains the process of creating genetically modified organisms and common examples.
β β β β± 10 min
Gene editing
Introduces modern targeted gene editing techniques including CRISPR-Cas9.
β β β β β± 10 min
Biotechnology applications
Covers real-world uses of genetic technology in medicine, agriculture and conservation.
β β β β± 12 min
2. Common Pitfalls
Wrong move:
Confusing species richness with species evenness when describing biodiversity
Why:
Richness only counts the number of different species, while evenness accounts for relative population abundance
Correct move:
Always clarify which measure of biodiversity you are referring to in exam responses
Wrong move:
Mixing up in-situ and ex-situ conservation strategies
Why:
The prefixes indicate where conservation takes place, not the type of species being protected
Correct move:
Remember: in-situ = in the natural habitat, ex-situ = outside the natural habitat
Wrong move:
Confusing genetic modification with gene editing
Why:
The two processes have different end results and methods
Correct move:
GM inserts foreign DNA from another species, while gene editing modifies the organism's existing DNA
3. Quick Reference Cheatsheet
Concept | Key Summary |
|---|---|
Simpson's Index of Diversity () | , higher = more diverse ecosystem |
Binomial Nomenclature | Two-name naming system: Genus species (Genus capitalized, italicized) |
In-situ Conservation | Conservation of species in their natural habitat (e.g. national parks) |
Ex-situ Conservation | Conservation of species outside natural habitat (e.g. seed banks, zoos) |
Polymerase Chain Reaction (PCR) | In vitro technique to amplify (make many copies of) a target DNA sequence |
Genetically Modified Organism (GMO) | Organism whose genome contains one or more foreign genes from another species |
CRISPR-Cas9 | Targeted gene editing system that cuts and modifies DNA at specific pre-selected sequences |
What's Next
Begin your study of this unit with the first sub-topic on biodiversity measurement, which lays the foundation for all subsequent topics on classification, conservation, and genetic technology. After completing all sub-topics in this unit, you will move on to the next unit of the CIE A-Level 9700 syllabus covering selection and evolution.