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: c) Some organisms rely on energy captured from inorganic compounds to drive basic biological processes.
Explanation:
Deep-sea hydrothermal vents are hot spots of geothermal water. The organisms living in deep-sea vents cannot obtain energy from sunlight. They are dependent on chemosynthesis, which involves the utilization of inorganic substances to produce organic substances, which allows their survival and act as a source of energy. In the given situation, bacteria present on the surface of mussels are capable of chemosynthesis also the mussels are dependent upon inorganic hydrogen in seawater. Thus chemosynthesis supports the survival of organisms living in the deep sea vents.
Skin, Hair, nails, and glands.
The integumentary system has the components of the
Epidermis, The epidermis is the most superficial layer of the skin that covers almost the entire body surface.
Hair.
Nails.
and the Sudoriferous Glands, Sebaceous Glands, and Ceruminous Glands.