What type of cross produces a 1 1 1 1 phenotypic ratio?

What type of cross produces a 1 1 1 1 phenotypic ratio?

dihybrid cross
In the monohybrid cross, a testcross of a heterozygous individual resulted in a 1:1 ratio. With the dihybrid cross, you should expect a 1:1:1:1 ratio!

What type of cross did Morgan perform here?

Female Gametes Moreover, all of the white-eyed F2 offspring were male. Next, as previously discussed, Morgan conducted a third cross to determine whether white eyes were lethal in female flies. Here, he bred red-eyed females (X +X w) with white-eyed males (X wY), as summarized in Table 5.

What proportion would have wild-type wings?

For example, the expected proportions of flies with wild-type and ebony body colours in a monohybrid cross are 3/4 and 1/4, respectively. Likewise, in a monohybrid cross involving vestigial wings, the proportions are 3/4 wild-type and 1/4 vestigial-winged.

What does a 1 1 ratio mean in genetics?

A 1:1 ratio among progeny suggest one gene is involved in the phenotype which would involve a cross between a heterozygote X homozygote parent. 5. A 2:1 ratio among the progeny suggest one gene is involved where the presence of both recessive alleles results in death (ex: Aa x Aa) 6.

Can female flies have white eyes?

All of the females and all of the males will have red eyes. All of the females will have white eyes; half of the males will have red eyes, and half of the males will have white eyes.

What was the most likely conclusion of Morgan’s research?

What was the most likely conclusion of Morgan’s research? The pigment in butterfly wings absorbs light from the environment. The phenotypic expression of wing shape depends on color pigmentation in butterflies. The genes regulating wing color in butterflies are influenced by environmental factors.

Are sepia eyes dominant or recessive?

Sepia eyes (se, 3; 26.0) are an autosomal recessive trait on Chromosome 3 that produces a dark brown eye color.

Is wild type always dominant?

Gain-of-function alleles are almost always dominant to the wild type allele. Hypermorph alleles produce more of the same, active product.