WJEC GCSE Biology: Cells, genetics and evolution (Unit 2) overview

This module covers how living things are classified, how cells divide, how characteristics are inherited, and how species change over time. It draws together the first four sections of WJEC Biology Unit 2: 2.1 Classification and biodiversity, 2.2 Cell division and stem cells, 2.3 DNA and inheritance and 2.4 Variation and evolution. This page maps the module and links to a focused answer page for each topic.

The cells, genetics and evolution content

Classification and biodiversity

The kingdoms and the taxonomic hierarchy, the binomial system, species, keys, and measuring biodiversity. See Classification and biodiversity.

Cell division and stem cells

Mitosis and meiosis, haploid and diploid, stem cells and their uses, and cancer. See Cell division and stem cells.

DNA and inheritance

DNA structure, genes, chromosomes and alleles, genotype and phenotype, Punnett squares and sex determination. See DNA and inheritance.

Genetic engineering and profiling

The transfer of genes, restriction enzymes and vectors, examples, and genetic profiling. See Genetic engineering and profiling.

Variation and evolution

Variation, mutation, natural selection and evolution, fossils, selective breeding, and antibiotic resistance. See Variation and evolution.

How this module is examined

This content is assessed on Unit 2, a written paper of 1 hour 45 minutes, worth 80 marks and 45% of the qualification, tiered at Foundation and Higher. Expect short answer, structured, data response and extended writing questions, including genetic crosses and natural selection explanations.

How to study this module

This module rewards confident genetics and clear sequences.

1. Master Punnett squares. The 3:1 and 1:1 ratios should be automatic.
2. Separate mitosis and meiosis. Numbers, identical or different, and their purposes.
3. Sequence the processes. Genetic engineering and natural selection both need ordered steps.
4. Learn the classification rules. Kingdoms, the hierarchy, and the binomial naming convention.
5. Use the resistance example. Antibiotic resistance is the classic natural selection question.

For the official specification

WJEC publishes the full specification, past papers and mark schemes at wjec.co.uk. Always revise from the current specification and WJEC's own past papers.