(C) it's genes and it's environment.
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:
Option a, survive in extreme environments
Explanation:
Both Thermus and Deinococcus belong to the group of bacteria that are collectively termed as Deinococcus–Thermus group.
Deinococcus are radiation-resistant vegetative cell as they are able to resist ionising radiation. Also some species of Deinococcus are thermophile.
Thermus are thermophilic bacteria that are able to live in extreme temperature condition and thus are able to tolerate high temperature.
Hence, option A is correct.
Answer:
Explanation:
1)Pfr/Pr
2) Pr
3)far-red
Explanation:
The leaves at the top of a tree’s canopy are exposed to direct sunlight during the day, and their phytochromes will occur in a high *Pfr/Pr* ratio. Meanwhile, the leaves of the same tree at the bottom of the canopy are highly shaded during the day and will likely have a higher proportion of the * ( PHYTOCHROME )Pr *;form of phytochrome present due to exposure to a higher proportion of *FAR RED * light.
Plants make use of the phytochrome system to it's adjust growth based on the seasons. Through phytochrome plants is able to respond to the timing and duration of dark and light periods. At dawn, all the phytochrome molecules present in the leaved are converted to the active Pfr form until sunset this is because the sun is unfiltered, and unfiltered sunlight has high percentage of red light, but lower far-red light, with the help of phytochrome system , the plants is able to compare the length of dark periods over several days.
