Answer:
A punnet square is a diagram which illustrates the results of a cross. The results from a cross between two homozygous dominant (PP) parents can be illustrated as follows:
P P
P PP PP
P PP PP
A dominant trait can be described as the one which suppresses the effect of a recessive trait.
The outcomes of this cross show that all of the offsprings produced will be homozygous dominant having purple colour.