Two genes in chromosome 7 of corn are identified by the recessive alleles g (for glossy leaves) and r (for branching of ears). When a plant heterozygous for each of these alleles was crossed to a double recessive plant, the progeny consisted of the following genotypes, with the numbers of each indicated Gr/gr 80 GR/gr 8 Gr/gr 10 gR/gr 77 What is the genotype of the double heterozygous parent?