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 results that have been produced from the improved agricultural practices are the following: increased biodiversity, increased productivity, and increased profits. Improved agricultural practices aim to produce food for consumers that are safe and wholesome. If these agricultural practices are improved and applied, there will be an increase in biodiversity as well as increased in productivity. If there is an increase in production, there is an increase in profits.
Answer:
4. A
4.(part 2) B
6. C
7. A
8. C
9. A
10. B
11. C
12. D
13. C
14. D
15. C
16. C
17. A
18. C
19. B
20. G
I Really hope this was helpful to you i tried my best to answer all the questions
Explanation:
The step that is part in the
formation of the batholiths is a single pluton enlarges into a huge mass by melting
the rock around it. A single pluton does not enlarge into a huge mass, instead,
it will melt due to the buoyant magma that surrounds it.
Birds, just like humans, have a four-chambered heart.