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:
Explanation:
The functional unit of the kidney responsible for excretion is the nephron . ... capillaries; Arcuate vein; Arcuate artery; Afferent arteriole; Juxtaglomerular apparatus ... If urine contains albumin or blood cells , it indicates that the glomeruli have been damaged. Binding to plasma proteins will influence urinary excretion .
Top-down effects imply control through predation, including fishery, while
bottom-up effects imply control through food abundance, often thought to be driven by climate or nutrient load.
<h3>What is Top down regulation ?</h3>
The top-down effect refers to a higher trophic level influences the community structure of a lower trophic level through predation.
<h3>What is Bottom up regulation ?</h3>
The bottom-up effect means that a lower trophic level in the biological network affects the community structure of higher trophic levels by means of resource restriction
Learn more about Top down and bottom up regulation here:
brainly.com/question/18996262
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They all go through a rotation in which one needs another
Becausebof he law of conservation of evergy. Evergy can not be created of eliminated, therefore it has to be transfered in this case the energy is transfered from one organism to the otherand this process continues at an endless cycle
