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:
Mutualistic means that both organisms benefit.
Explanation:
The acacia tree provides shelter and food to the ants, while the ants protect the tree from other animals.
The answer would be D. Huntington's disease presents symptoms in humans after many have already reproduced; therefore, they are unaware that they passed on Huntington's disease.
Hhv-5 infectious in pregnant women can be particular concern because this virus can be teratogenic.
<h3>
What is teratogenic?</h3>
- Teratology is the study of aberrant physiological development across the whole life cycle of all species, including plants.
- Dysmorphology is a branch of medical genetics that focuses on the classification of congenital deformities.
- Teratogens are substances that, when exposed to a pregnant woman, may result in physical or functional abnormalities in the human embryo or fetus.
- Such substances include, for example, alcohol and cocaine.
- A teratogen is an agent that increases a baby's risk of developing a birth defect or can actually cause one.
- They are items to which a mother might be exposed while expecting.
- Teratogens can result in neural tube abnormalities like spina bifida during this time.
- Throughout the entire pregnancy, certain organs are vulnerable to teratogens.
- The baby's brain and spinal cord are included in this.
- Alcohol can be harmful at any point during pregnancy since it has an adverse effect on the brain and spinal cord.
Learn more about teratogenic here:
brainly.com/question/14970129
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