Answer:
More than one gene is controlling the loss train of that eye. Thus, the Cross among the scarlet and grey species, F1 crossover has fractional eyes. Despite the fact that both sort of cavern fishes are visually impaired, yet cross between them has brought about offspring with fractional eyes. This shows multi-gene legacy for eye misfortune attribute. Blending of two genotypes has brought about incomplete characteristic in the descendants.
The woolly mammoth was an animal used to artic, or colder conditions. When the Ice Age ended, the woolly mammoth couldn't handle the warmer temperatures. It also was being hunted for food. People could have hunted it out of extinction.
I hope this helped you!
Brainliest answer would be appreciated!
Explanation:
The problem says that the hairless phenotype never breeds true. That means that it's not the result of a homozygous genotype (H₁H₁ or H₂H₂), so it is caused by the heterozygous genotype (H₁H₂).
The <u>expected </u>offspring from the cross between two Mexican hairless would be:
<h3>P
H₁H₂ x
H₁H₂</h3><h3>F1 1/4
H₁H₁, 2/4
H₁H₂ and 1/4
H₂H₂.</h3>
And the <u>expected</u> phenotypic ratio 3:1. However, the observed offspring shows a 2:1 ratio. What's happening?
If the observed phenotypic ratio in the offspring of a monohybrid cross (a single gene with two alleles) is 2:1, we can suspect that one of the genotypes is lethal in homozygosis and therefore does not appear in the progeny (the puppies are born dead).
If we proposed that the H₂ allele is lethal in homozygosis, then:
- The H₁H₁ genotype would cause normal puppies --> 1
- The H₁H₂ genotype would cause hairless puppies --> 2
- The H₂H₂ is lethal and causes the death of puppies --> 0
The phenotypic ratios change to 2:1, as observed in the experiment.
The answer would be B. chromosome 21
