The role of genes in controlling inherited characteristics is described. The terms dominant and recessive are defined. Eye colour is used as an example and the combination of two recessive genes is used to explain how people can have blue eyes.

First broadcast:
21 November 2008

Ask student to bring in family photos and discuss in class the inherited features that can be seen. Students should attempt to explain inheritance in terms of genetic information. The idea of dominant and recessive genes can be discussed in relation to features that can be seen to skip generations, or which are inherited by some children but not others.