A pure breeding pea plant with the dominant phenotype of character A and recessive phenotype of character B was crossed with another pure breeding plant with the recessive phenotype of character A and dominant phenotype character B. Offspring of this cross was crossed with a homozygous recessive for both the characters A and B. The following results were obtained.
22 were phenotypically dominant of A and recessive of B
22 were phenotypically recessive for both A and B
22 were phenotypically recessive for A and dominant for B
22 were phenotypically dominant for both A and B
The results show that
(1) genes A and B are linked
(2) independent segregation of genes A and B
(3) Mendelian dihybrid inheritance
(4) polygenic inheritance.