Deoxyribonucleic acid is a chemical that carries genetic information, and it is the molecule of inheritance.

the sequence of DNA that codes for a particular protein

diagrams that show the evolutionary relationships between organisms

Classification and reclassification: genetic evidence

Combined science

Classifying organisms as eukaryotic or prokaryotic

Electron microscopy, and the size and scale of cells: including standard form

Classification into kingdoms and domains: sub-cellular evidence

Pupils learned that random genetic mutation is a source of heritable variation, and that evolution occurs through the natural selection of genetic variants linked to advantageous phenotypes.

This unit explores the impact of biology developments on classification systems, highlighting how electron microscopy enhances understanding of sub-cellular structures. It covers eukaryotic and prokaryotic cells, quantitative skills, unit conversions, and the evolution of scientific methods.

Classification in modern biology

The model shown in the diagram is an evolutionary ...

According to this evolutionary tree, which two organisms are most closely related?

Which branching point, P, Q, R or S, shows the most recent common ancestor of species A, B, and C?

Which species is most closely related to species G?

How many differences are there between the gene sequence of species G and that of species J?

Which evolutionary tree shows the relationship between the species shown in the table?

Which classification group would contain the most organisms? 

extremophiles that live in extreme environments

Match the names of the three domains to the organisms that are classified into them. 

What is the primary characteristic that distinguishes eukaryotic cells from prokaryotic cells?

introduction of the binomial naming system

What major advancement did Carl Woese contribute to the field of classification?

What are the three domains proposed by Carl Woese in his classification system?

based on genetic similarity and differences

based on their observable and measurable characteristics

How did Linnaeus classify organisms in his classification system?

Starter Quiz

Which classification group would contain the most organisms?