The Story of an Hour Theme of Freedom and Confinement. At first, freedom seems like a terrible thing to Mrs. Mallard, who's restricted in lots of ways: through her marriage, by her bad heart, and even inside her home, which she doesn't leave during "The Story of an Hour."
MRNA, is used to transcript DNA codes from DNA molecules and then later exits the nucleus via nuclear pore, then moves to the ribosome. Then, tRNA is activated to bring specific amino acid to the ribosome for translation. Ribosome, which is the site of synthesis of proteins, is composed of rRNA and ribosomal proteins.
A codon is a three-base sequence (three nitrogen bases in a row) on mRNA. An anticodon is a three-base sequence on tRNA. It matches the codon.
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.
