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After telophase I of meiosis, the chromosomal makeup of each daughter cell is…

Consider the following cross of two individuals: AaBB x Aabb, where the two genes assort independently. The expected genotypic ratios of this cross are given by:

Yellow birch (Betula cordifolia) and mountain birch (Betula alleghaniensis) have overlapping ranges. Pollen grains from one species are unable to germinate and make pollen tubes on female ovules of the other species. These two birch species are kept separate by _______.

Five male colonists and five female colonists (all unrelated to each other) settle on an isolated island. The colonists and their offspring randomly mate for generations. All ten of the original colonists were right-handed and three were heterozygous for the trait. The allele for right-handedness is dominant to the allele for left-handedness. a. If one assumes that Hardy-Weinberg equilibrium applies to the population of colonists, about how many people could be expected to be left-handed when the population reaches 10,000? Show how you set up your calculation. b. If four of the original colonists died accidentally before they produced offspring, the ratios of genotypes could be quite different in the subsequent generations. This would be an example of what process affecting the population’s frequency of alleles?

In a hypothetical situation, a certain species of flea feeds only on pronghorn antelopes. In the western United States, pronghorns and cattle often associate with one another in the same open rangeland. Some of these fleas develop a strong preference for cattle blood and mate only with other fleas that prefer cattle blood. The host mammal can be considered as the fleas’ habitat. If this situation persists, a new species can evolve. This would be an example of what?

List the five Hardy-Weinberg assumptions and give one sentence for each on how they could be violated.

Which mechanism would reverse speciation?

Dwarf Cavendish bananas are the most common banana on grocery shelves. They are triploid, meaning that they have three sets of chromosomes. Because of this, meiosis and creation of gametes is not possible, and cultivation depends on vegetative propagation through mitotic divisions. This information leads to which of the following conclusions?

Give two differences and two similarities between Meiosis II and Mitosis.

In an environment in which members of a population compete with each other for resources, a change occurs that selects against members that exhibit a particular dominant trait (the trait exhibits complete dominance). Which of the following graphs best depicts the trends in genotypic frequencies that would be expected to occur over time?