Genetics is the field of biology devoted to understanding how characteristics are transmitted from parents to offspring. Genetics was founded with the work of Gregor Mendel In 1851, Mendel entered the University of Vienna to study science and math. He did a research on heredity, which is the transmission of characteristics from parents to offspring. He is remembered most from his experiences with garden peas.

Mendel observed seven characteristics of pea plants. A trait is a genetically determined variant of a characteristic. The pea characteristics he observed were, plant height, flower position along stem, pod color, pod appearance, seed texture, seed color, and flower color.

Mendel collected seeds from his plants and recorded each plant's traits and seeds. The following year he planted the seeds. He observed that both the purple and white flowers grew from seeds of the purple flowers. With height both the tall and short plants grew from seeds from the tall plants. He wanted to find out why that was happening.

Mendel was able to observe how traits were passed by controlling how pea plants were pollinated. Pollination is when pollen grains produced in anthers are transferred to the stigma.

Self pollination is when pollen is transferred from the anthers to the stigma of that flower or the same plant.

Cross-pollination occurs between flowers and two plants. By preventing self pollination and cross pollinating pea plants, Mendel selected parent plants that had specific traits and observed traits that appeared in the offspring.

Mendel initially studied each characteristic and its contrasting traits individually. He started my growing plants that were were true breeding each trait. True-breeding is a trait that always produces offspring with that trait when they self-pollinate.

Mendel produced true-breeding plants by self-pollinating the pea plants for several generations. He eventually obtained 14 true-breeding plant types, one for each of the 14 traits observed. Mendel called the true-breeding parents the P generation. The P generation is parental generation which is the first two individuals that mate in a genetic cross.

Mendel cross pollinated by transferring pollen from the anthers of one plant to the stigma of another plant. He dusted the pollen from a yellow podded plant onto the stigma of a green podded plant and allowed the seeds to develop. He called the offspring of the pea generation the first F-1 generation. F-1 generation is the first generation of offspring obtained from an experimental cross of two organisms. He then allowed the flowers from the F-1 generation to self pollinate and collected the seeds. When he did this he called it the F-2 generation. F-2 generation is the second generation of offspring.