Given that green pea pods are dominant over yellow pods , cross two heterozygous green plants

When Two heterozygous plants with Green Pod are crossed

The phenotype ratio of Green pod: yellow pod Plant = 3:1

The Genotype ratio is 2:1:1

Explanation:

Observe the Punnett's Square in the attachment:

Heterozygous individual has two different alleles of the same gene one of which is diominant and the other is recessive.When Heterozygous Individual's cell undergoes meiosis the two alleles segregate and each gamete recieves either of the alleles.When two heterozygous plants are crossed there are chances that Gametes with  dominant alleles fuse producing a homozygous dominant (YY), a gamete with dominant allele fuses with a gamete having recessive allele producing a Heterozygous (Yy) individual showing dominant trait or a gamete with recessive allele fuses to produce a homozygous recessive (yy).

From a high concentration to a low concentration.