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.
Answer:
8-b!!!!!!!!!!!¡!!!!!!!!!!!!!
765 areas in the united states
Answer:
Sinh vật nhân sơ chỉ có một RNA Polymerase, trong khi sinh vật nhân chuẩn có ba (RNA Polymerase I, phiên mã rRNA; II, phiên mã mRNA; và III, phiên mã tRNA).
A. The following statements are hypotheses:
1. Glucose may cause an increase in bacterial growth.
2. Increased glucose may lead to capsule formation in bacteria.
B. The following statements are observations:
1. The bacterial colony grown without glucose do not have capsules around their cells.
2. Bacteria growth in the glucose environment increase rapidly and then stopped after sometime.