How do dominant and recessive alleles help determine your phenotypic expressions?
Phenotype are the traits an organism expresses. Dominant alleles only need one copy of that allele to be expressed. Therefore, if T represents the allele in pea plants for tall which is dominant, and t represents the allele for short height which is recessive, a pea plant with TT or Tt will both have a tall phenotype. A recessive allele when paired with a dominant allele, remains hidden. To express a recessive trait, an organism must have two recessive alleles. If a pea plant has a genotype-- tt, then this pea plant would have a short phenotype.