"Disruptive selection" is the one mechanism among the choices given in the question that <span>brought this change in gene frequencies. The correct option among all the options that are given in the question is the fourth option or option "D". I hope that the answer has actually come to your help.</span>
The correct answer is; D
Homologous structures is the term used to describe physical similarities between related species that indicates a common ancestry.
Homologous structures are structures that have the same form or functions in different animals, indicating that the animals have evolved from a common ancestor. Homologous structures usually appear very similar in form but it may or may not have the same function in the different animals that are suggested to be related. The bones in the front limbs of many different mammals (such as humans, deer and bats) which are similar in their structure and arrangement are homologous structures.
Answer:
a.The phenotypic proportions obtained after having the genotypes are 50% marbled seeds, 25% spotted and dotted seeds since they are codominant, 25% spotted seeds.
b. Taking into account the F1 genotypes in the previous point, the expected phenotypes for the first crossing are 100% marbled seeds and for the second crossing 100% dotted seeds.
Explanation:
Let's suppose:
Marbled allele: M
Spotted allele: S
Dotted allele: D
Allele for Clear: C
a. Because both crosses were between homozygous parents, the entire F1 genotype is the same.
For the first crossing the descendants have the MS genotype, and for the second crossing the descendants have the DC genotype. It is enough to make a Punnett square to obtain the different combinations of genotypes between the crossing of MS and DC.
An error is that the scientist did not control their variables. They had one group of people playing the game at 6, and another group playing at 12. This means that other things might have affected the scores other than what was being tested, which was caffeine.