Inheritance

Inheritance is the process by which genetic information is passed from parents to offspring. This topic covers the structure and function of DNA, genes, and chromosomes, and explains how traits are inherited through generations. You will learn about key concepts such as alleles, dominant and recessive traits, and how genetic diagrams (Punnett squares) can predict the probability of certain characteristics appearing in offspring. Understanding inheritance is crucial for explaining genetic variation, evolution, and the basis of many inherited disorders.

In WJEC GCSE Biology, inheritance is a core topic that links to cell division (mitosis and meiosis), variation, and natural selection. You will explore the work of Gregor Mendel, the father of genetics, and apply his principles to solve problems involving monohybrid crosses. The topic also introduces the role of DNA in coding for proteins, and how mutations can lead to changes in traits. Mastering inheritance helps you understand real-world applications like genetic engineering, selective breeding, and genetic screening for diseases.

This topic is not just about memorising definitions; it requires you to interpret and construct genetic diagrams, analyse pedigree charts, and explain patterns of inheritance. You will need to use correct terminology (e.g., homozygous, heterozygous, genotype, phenotype) and apply mathematical ratios to predict outcomes. A solid grasp of inheritance is essential for higher-level study in biology and for understanding contemporary issues such as gene therapy and the ethics of genetic modification.