Mendel spent years crossing pure bred pea plants together to observe their phenotypes. One consistent pattern he observed is that every time a pure breed purple flower was crossed with a pure breed white flower, all offspring were purple. What does this tell you about the purple color flower in pea plants?

The purple colour of the flower is homozygous and dominant to white flowers in pea plant.

Explanation:

In Mendelian Genetics the dominant allele is always expressed masking the recessive allele in between dominant and recessive alleles.

It is present when two copies of the dominant gene are present.

Suppose a purple flower plant is crossed by white flower.

Purple flower PP  and white flower is pp

  P    P

p Pp  Pp

p Pp  Pp

all the flowers formed are heterozygous and exhibit purple colour flower.

Thus we can see the purple colour is dominant  and heterozygous.