In pea plants, purple flower color (P) is a dominant allele, while white flower color (p) is recessive allele. If a pea plant has the genotype Pp, what is it's phenotype? Explain your answer.

phenotype will be purple colour

when we say that a trait is dominant it means that it require only one allele to be expressed where as when we say that a trait is recessive it means it will only be expressed with both of the alleles...now since white colour is recessive, it needs 2 alleles to be expressed and in the aforementioned case, it will not be expressed because it have only one allele...where as purple colour, being dominant will be expressed even with single allele...