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WalesCombined Science

Unit 4 Biology 2: Cells, genetics and evolution

4 dot points across 4 inquiry questions. Click any dot point for a focused answer with worked past exam questions where available.

How do cells divide by mitosis and meiosis, and what are stem cells used for?

Cell division by mitosis and meiosis, the differences between them, and stem cells and their uses.
A focused answer to the WJEC GCSE Science Double Award Unit 4 topic on cell division, covering mitosis and meiosis and the differences between them, and stem cells and their uses in growth, repair and medicine.
9 min answer →

How are living things classified, and why does biodiversity matter?

The classification of living things into groups, the use of keys to identify organisms, and the importance of biodiversity.
A focused answer to the WJEC GCSE Science Double Award Unit 4 topic on classification, covering how living things are classified into groups, using keys to identify organisms, and why biodiversity is important and how it is protected.
9 min answer →

What is DNA, and how are characteristics inherited through dominant and recessive alleles?

DNA, genes and chromosomes, dominant and recessive alleles, and using genetic diagrams to predict the inheritance of a characteristic.
A focused answer to the WJEC GCSE Science Double Award Unit 4 topic on inheritance, covering DNA, genes and chromosomes, dominant and recessive alleles, genotype and phenotype, and using a genetic (Punnett) diagram to predict inheritance.
10 min answer →

What causes variation, and how does natural selection lead to evolution?

Genetic and environmental variation, the theory of evolution by natural selection, and the evidence for evolution.
A focused answer to the WJEC GCSE Science Double Award Unit 4 topic on variation and evolution, covering genetic and environmental variation, evolution by natural selection, and the evidence for evolution including fossils and antibiotic resistance.
9 min answer →