3 Patterns of inheritance

We can trace the inheritance of characters in animals and plants by following the phenotype from generation to generation, in breeding experiments. We will describe work with maize (Zea mays), alternatively called corn (sweetcorn, or corn on the cob), which occurs throughout the world as an extremely important commercial crop plant, and which is used extensively in genetic research. We can also study the inheritance of characters at the level of the genotype. In this section we will jump between these two levels, and in so doing we shall be jumping from the fundamental work of 19th century biologists, who could only trace phenotypes, to that of present-day geneticists, who work at the level of the gene.