IB Biology Sub-topic A3.1 Definitions

This page contains our IB Biology definitions for sub-topic A3.1. By learning each one of these definitions, you will fully cover the content for IB Biology 'Further diversity'.
HL
artificial classification

Classification of species on the basis of visual observation

HL
cladistics

The study of classifying clades

HL
Dichotomous Key

A tool used for identifying organisms based on a series of choices that lead to the correct name of the given item

HL
DNA Barcodes

Short sequences of conserved DNA that are specific and unique to each species, used for species identification

gene

A heritable factor that consists of a length of DNA and influences a characteristic

HL
Invasive Species

Non-native species that spread widely in a new habitat, often causing harm to the environment, economy, or human health

HL
natural classification

Classification of species on the basis of genetic similarity

species

A group of organisms that can potentially interbreed

Great Work!

You have now covered all of our topic 3 definitions for IB biology.
Now that you have completed these IB biology topic 3 definitions, dive into our topic 3 videos for the IB biology course.
IB biology topic 3 videos

Explored IB Biology?

Get stuck into one of our other subjects!
Join 85,000 students, across 130+ countries, in 500+ IB schools. That's half of the IB science graduates worldwide.
Start a 7d free trial