Imagine that you have crossed two types of peonies, one with purple flowers and long stems, and the other with white flowers and short stems. When you cross these flowers, you get the following numbers of progeny: 83 with purple flowers and short stems; 29 with purple flowers and long stems; 26 with white flowers and short stems; and 9 with white flowers and long stems. Based on these data, what can you say about genes that define flower color and stem length?

A dominant allele can be described as the one which masks the effect of a recessive allele. A recessive allele can be described as the allele which gets masked by the dominant one. If alleles for a gene are heterozygous then most likely the effects or traits of the dominant allele will be seen in the phenotype of the organism.

As we can see in the question, the number of purple flowers heavily outnumbered the white flowers, hence we can say that the purple colour is dominant over the yellow colour.

As we see that the number of short stems were more than the number of long stems, hence short stems were the dominant character.

We can also predict from this experiment that alleles assort independently during gamete formation.