Unit 7 Progress Check: MCQ Part B

Which of the following sets of data provides evidence that best supports common ancestry for organisms in all three domains?

Which statement below best states an alternative hypothesis Fox could have used to frame his research?

Iridium is an element that is rare on Earth but commonly found in meteorites. A scientist believes that the first organic molecules may have come to Earth on meteorites 3.6 billion years ago. Which of these would be an appropriate null hypothesis to test related to whether meteorites hit the Earth 3.6 billion years ago?

Based on the data in Figure 1, which of the following would most affect the allelic frequencies of the populations on Isabela and Butuan?

Which of the following best explains the trend shown in Figure 1? (Kentucky Derby)

There are two species of elephant seals: northern elephant seals, Mirounga angustirostris, found off the western coast of North America from Baja California to the Gulf of Alaska, and southern elephant seals, M. leonina, found in the southern oceans. Hunting in the nineteenth century has been blamed for a drastic reduction in the northern elephant seal population. Even though the population has rebounded following restrictions on seal hunting, genetic variation is greatly reduced in the northern species compared to that in the southern species. Which of the following conditions of Hardy-Weinberg equilibrium was most likely not met in the northern elephant seal population following overhunting?

In a certain small mammal, fur color is controlled by a pair of alleles, with B being dominant over b. The genotypes BB and Bb result in dark-colored fur, the genotype bb results in light-colored fur. A population of the species has the following allele frequencies: B=0.85 and b=0.15. If a fire caused the surface of the ground in the habitat of the species to become darker in color, which of the following claims about the impact on the allele frequencies in this population is most reasonable?

A group of researchers noticed that using a particular drug to treat cancer in mice would reduce the size of the tumor, but some of the tumor cells appeared to be resistant to the drug since some of these cells would increase in number over time. The researchers wish to increase the reliability of their experimental observations before investigating new claims that chemotherapy-resistant tumors are an example of continuing evolution. Of the following, which is the best next step the researchers might take to increase the reliability of their evidence?

A population geneticist is conducting an investigation on a population of mice. The geneticist determines the genotypes for a particular trait of all of the mice in the population during generation 1 and then removes all of the mice with the genotype aa. The remaining members of the population are allowed to randomly mate with one another to produce generation 2 and future generations. A model of the investigation is shown in Figure 1. Each of the fifteen genotypes shown in generation 1 and generation 2 represents 100 mice. Figure 1. Model of effect of selective mouse removal on a population Which of the following best illustrates the change in the frequencies of the A and a alleles from generation 1 to generation 2 and to future generations, assuming Hardy-Weinberg equilibrium is present after generation 1 ?

A scientist is studying the impact of mutagens on genetic variation in mice. In an experiment, the scientist creates two groups of twenty highly inbred mice. Because the mice are highly inbred, they are essentially identical to one another. One group is given food with an added substance that is known to be a mutagen. The second group is fed the same food without the mutagen. After several generations, both groups of mice are given a new type of food that is harder to digest than the previous food. After rearing five additional generations of the mice on this new food, the two groups are assessed for how efficiently this new food is digested. Which of the following is the most reasonable prediction about the results of the experiment?

Which of the following best explains the divergence in morphology in the birds?

A group of researchers claim that chance events play an important role in the evolution of populations. To test their claim, they monitored 12 populations of E. coli for 10,000 generations under the same environmental conditions. They found that although all 12 populations were exposed to the same environmental pressures, each population had differentiated from one another genetically after 10,000 generations. Which of the following statements includes a reasonable refinement that researchers could use in repeating the experiment?

Some scientists propose that due to human activity and climate change, a sixth mass extinction has already begun. Select the best alternate hypothesis to support this claim.

A scientist maintains a large population of the fruit fly Drosophila affinis in the laboratory. After 20 generations of allowing this population of about 1000 flies to mate randomly, 10 females and 10 males were isolated from the rest of the population. Both the larger population and the isolated population were maintained under identical conditions and allowed to mate randomly for another 20 generations. After the 20 generations, DNA sequencing was used to determine the genetic composition of each population. Which of the following predicts the expected outcome of the experiment?

Human activities can drive changes in ecosystems that affect the risk of extinction. An experiment is designed to help prevent the further decline and extinction of the Henslow's sparrow in which controlled burns will be set in the each of the ten Midwest counties in order to prevent the regrowth of the forest. Which of the following represents an alternate hypothesis tested by this experiment with regard to the population sizes of Henslow's sparrows?

Which of the following best predicts why the recombinant bacteria will fail to produce the eukaryotic protein?

Which of the following best predicts why humans and mice have identical telomeric repeat sequences?

Which of the following would most likely represent the types of individuals found in one of the species resulting from shape becoming a prezygotic isolating mechanism in the initial population represented in Figure 1 ?