Question: In Drosophila melanogaster, eyeless (ey) is a recessive trait in which the eyes are tiny or absen…

In Drosophila melanogaster, eyeless (ey) is a
recessive trait in which the eyes are tiny or absent. The
ey locus is found on chromosome 4. Monosomy and trisomy
for this very small chromosome are compatible with survival and
fertility. A trisomic wild-type male with the genotype
ey⁺ ey⁺ ey is crossed to an
ey⁺ ey female. Assuming random segregation of
chromosomes into gametes, determine the chromosome constitution and
phenotypic ratios in the offspring.