Biology Quiz

Which of the following is closest to the frequency of the MC1RD��1�� allele in the Tule Mountain population?

0.03

In addition to the ABO blood groups, humans have an MN blood type system in which the � and � alleles are codominant to one another. A group of scientists found that in one population the frequency of the � allele was 0.82, and the frequency of the � allele was 0.18. Assuming that the population is in Hardy‑Weinberg equilibrium, which of the following is the expected frequency of individuals with the genotype ��?

0.295

Researchers have undertaken a long-term study of populations of rock pocket mice, Chaetodipus intermedius, in Arizona and New Mexico. Rock pocket mouse fur is either dark or light in color. Most of the populations studied live in areas with light-colored granite rocks; however, some areas are dominated by dark-colored rocks from ancient lava flows. Researchers collected mice from six sites in Arizona and recorded their coat colors. Figure 1 shows the study sites, the rock colors, and the distribution of coat colors. In the Arizona populations, the melanocortin-1 receptor (MC1R)(MC1R) gene is responsible for coat color phenotype (light or dark). The MC1RDMC1R⁢D allele, which results in a dark coat, is dominant to the d� allele. Researchers collected samples of mice from all six study sites and sequenced the MC1R��1� gene. They also collected mice with dark coats from a location in New Mexico, the Carrizozo lava flow, to determine if the MC1R��1�gene was also responsible for the dark coat colors observed in that population. The rock pocket mouse population in Carrizozo is isolated from the populations in Arizona. Table 1 presents the genotypic data from sampled mice from all seven locations. Owls (primary predators of rock pocket mice) are nocturnal visual predators that are able to distinguish effectively between dark and light colors in low-light conditions. Which of the following best explains the relationship between coat color and predation rate in the rock pocket mouse population on the lava flow rocks with respect to the different coat color phenotypes?

A dark coat color provides camouflage to mice on the lava flow rocks; therefore, mice with dark coats have a lower predation rate in that habitat.

One facet of the study of the origin of life focuses on the nature of the first genetic material. Figure 1 describes a possible scenario, known as the RNA World Hypothesis, that could have led to the evolution of our modern-day genetic material. This hypothesis states that the first genetic material was RNA, not DNA, and a transitional period led to the emergence of DNA as the storage molecule for genetic material. A scientist wishes to provide experimental evidence to support the model shown in Figure 1 by demonstrating the ability to synthesize an RNARNA molecule. Which of the following is an alternative hypothesis that can be tested to support the RNARNA World Hypothesis?

A mixture of ribonucleotides such as adenine and uracil will spontaneously form single-stranded chains of RNARNA.

Thoroughbred race horses are subject to intense artificial selection to produce faster-running horses. The results of breeding programs can be seen in the change in winning times of the Kentucky Derby from 1880 to the present, as shown in Figure 1. Figure 1. Best-fit curve for winning times in the Kentucky Derby since 1880 Which of the following best explains the trend shown in Figure 1?

By 1940, most genetic variation for speed had been lost from the gene pool.

Catalase is a protein enzyme that catalyzes the breakdown of hydrogen peroxide (H2O2)(H2O2) into water and oxygen gas in the cells of many living organisms. Students used an online database, which used the structure of catalase from different species, to generate the phylogenetic tree shown in Figure 1. Which of the following student claims is best supported by the data provided?

Cattle and sheep are separated by only one node, and they are separated from the other organisms by more than one node.

Figure 1 shows some major structural changes between a typical prokaryotic cell, the first eukaryotic common ancestor, and the last eukaryotic common ancestor. Based on the information provided in the figure, which of the following best describes how membrane-bound organelles provided unique evolutionary advantages to the last eukaryotic common ancestor?

Cells with mitochondria were able to utilize metabolic energy more efficiently.

Of the following, which is the best next step for the researchers to best determine the long-term effectiveness of these insecticides with regards to the development of resistance?

Continue treating the three insect populations with the same insecticides and determine whether their efficiencies decline significantly after several generations.

Which of the following represents an alternate hypothesis tested by this experiment with regard to the population sizes of Henslow's sparrows?

Controlled fires in counties 4 and 5 will lead to an increase in the sparrow population.

Whales, bony fishes, and cartilaginous fishes all have similar adaptations that enable them to live in the ocean. Figure 1 shows the phylogenetic relationships of selected vertebrates. Based on the phylogenetic relationships shown in Figure 1, which of the following best explains the similarities exhibited by whales, bony fishes, and cartilaginous fishes?

Convergent evolution, because these organisms do not share a recent common ancestor.

Researchers have undertaken a long-term study of populations of rock pocket mice, Chaetodipus intermedius, in Arizona and New Mexico. Rock pocket mouse fur is either dark or light in color. Most of the populations studied live in areas with light-colored granite rocks; however, some areas are dominated by dark-colored rocks from ancient lava flows. Researchers collected mice from six sites in Arizona and recorded their coat colors. Figure 1 shows the study sites, the rock colors, and the distribution of coat colors. Figure 1. Rock color and coat color at three sites on a lava flow (West, Mid, and East), and three nearby sites: O'Neill Hills (O'Neill), the Tule Mountains (Tule), and Christmas Pass (Xmas) In the Arizona populations, the melanocortin-1 receptor (MC1R)(MC1R) gene is responsible for coat color phenotype (light or dark). The MC1RDMC1R⁢D allele, which results in a dark coat, is dominant to the d� allele. Researchers collected samples of mice from all six study sites and sequenced the MC1R��1� gene. They also collected mice with dark coats from a location in New Mexico, the Carrizozo lava flow, to determine if the MC1R��1�gene was also responsible for the dark coat colors observed in that population. The rock pocket mouse population in Carrizozo is isolated from the populations in Arizona. Table 1 presents the genotypic data from sampled mice from all seven locations. Which of the following best describes the processes occurring between the mouse populations and their environments?

Dark color is selected for in mice from the West, Mid, and East populations.

A 100 acre woodlot was observed for the last forty years. Five plant species (1 through 5) were surveyed, with the results shown in Table 1. Some researchers claim that the decrease in plant species richness of this woodlot is unrelated to human activities over the last forty years. Which of the following would be an appropriate alternative hypothesis?

During the last few decades, tall buildings have been built around the woodlot, and species 3, 4, and 5 are shade‑intolerant plants

Geologic events such as mountain building can directly affect biodiversity. The Sino‑Himalayan fern, Lepisorus clathratus is widely distributed on the Qinghai‑Tibetan plateau. If geologic events lead to a series of new mountain ranges that divide the plateau into several discrete valleys, which of the following best describes how the L. clathratus population would be affected?

Geographic isolation will create separate gene pools, leading to speciation over time

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

Humans and mice share a recent common ancestor that had the 5′-TTAGGG-3′5′-TTAGGG-3′ repeat sequence in its telomeres.

The peppered moth, Biston betularia was generally white in color with black speckles. Over time a more solid black moth became the more common variety. Which of the following best explains the relationship between wing pigmentation and the coloration of a moth's surroundings?

If the surroundings of the peppered moth became darker, those backgrounds conferred a selective advantage to a black variety, as described by natural selection.

In addition to the ABOABO blood groups, humans have an MNMN blood type system in which the M� and N� alleles are codominant to one another. These alleles code for glycoproteins that act as antigens on the red blood cells. Scientists determined the frequencies of the M� and N� alleles in three localized and stable human populations in the Philippines. In Isabela, M and N alleles had a frequency of .8 and .21, respectively. Butuan had M and N allele frequencies of .82 and .18, respectively. Metro Manila had M and N allele frequencies of .55 and .51, respectively. Which of the following would most affect the allelic frequencies of the populations on Isabela and Butuan?

Immigration of individuals from Metro Manila into the two populations

The heterotroph hypothesis of the origin of life states that basic organic building blocks formed from inorganic molecules under the primitive conditions present early in Earth's development. These building blocks combined to form polymers, such as crude proteins. Dr. Sidney Fox wished to add to the heterotroph hypothesis of the origin of life by synthesizing simple proteins from a mixture of amino acids. Which statement below best states an alternative hypothesis Fox could have used to frame his research?

In the presence of available energy and the absence of a significant quantity of atmospheric O2O2 simple proteins will form spontaneously from a mixture of amino acids.

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?

Increasing the number of trials and the number of mice in each treatment group

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

Introns must be removed from eukaryotic DNADNA before the gene is inserted into the plasmid.

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?

Large population size

Mollusk fossils were excavated and collected from a coastal cliff. Scientists studying the fossils observed patterns of changing shell shape in the mollusks. The scientists identified a period of stability or stasis, followed by rapid change, and then stasis again with regard to shell shape. Which of the following statements best predicts the result of a comparison between the fossils found before and after the period of rapid change?

Most of the species found in the first static period will be absent in the second static period

Students created a model showing one possible mechanism for speciation in which a geographic barrier separated one large population into two smaller populations, A and B. Over time, populations A and B developed into two distinct species. The model is shown in Figure 1. Which of the following best describes what occurred during the periods indicated by the arrows?

Natural selection acted on variation that was present in both populations A and B, and the lack of gene flow eventually led to the formation of two new species.

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.

Observed modern extinction rates will resemble the rates found early in previous extinctions.

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

Organisms in Bacteria, Archaea, and Eukarya each have adenine, thymine, guanine, and cytosine bases forming their DNADNA.

Because cheetahs, Acinonyx jubatus, experienced a bottleneck event about ten thousand years ago, living cheetahs exhibit very little genetic variation compared to other living species of large cats. Which of the following principles best justifies a claim that cheetahs, compared to other large cats, have a relatively low resilience to environmental perturbations?

Populations with little genetic diversity are less likely to contain individuals that can withstand different selective pressures.

In a particular region, a species of lizard lives in the lowlands. Even though there are numerous mountains in the region, the climate on the mountains is too cold for the lizards to survive. Scientists are concerned that the lowlands will become much warmer by the end of the twenty-first century and will become unsuitable for this lowland lizard species. Which of the following best predicts the impact on the lizard species if there is a gradual increase in the average temperatures found in both the lowlands and mountains in this region?

Some lizards will migrate to new habitats in the mountains and become isolated, leading to allopatric speciation.

Scientists want to determine the age of four fossil specimens. They have analyzed the fossils and gathered the data shown in Table 1. Which of the specimens indicated in the table is the oldest?

Specimen 4

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?

Start each population with genetically identical bacterial cells from a single culture to make sure that the initial genetic variation in all of the populations was exactly the same.

The degrees of relatedness in several native populations of prairie chickens in Marion and Jasper Counties in Illinois were determined. The degree of relatedness is inversely proportional to genetic diversity; that is, populations with a high degree of relatedness have less genetic diversity. Table 1 shows the collected data. Populations J1 through J5 are located in Jasper County. Populations M1 through M5 are located in Marion County. Numbers above 0.125 indicate a high degree of relatedness. Scientists claim that some of the populations in Marion County are at an increased risk of decline or extinction. Based on the data in table 1, which of the following best provides evidence to support this claim?

The M4M4 and M5M5 populations have the lowest genetic diversity of all populations.

Based on the data in Table 1, which of the following best describes the relationship between the MC1R��1� gene and coat color in the Carrizozo, New Mexico, rock pocket mouse population?

The MC1RD��1�� allele is not responsible for dark coat color in the Carrizozo population, so the dark coat color is likely a result of convergent evolution.

The distribution of four populations of giant kangaroo rats, Dipodomys ingens, living on the same island when it was first surveyed in 1789 are shown in Figure 1. In 1852, there was a large earthquake which altered the island's geography, as shown in Figure 2. The island was surveyed again in 2015, and scientists determined that the giant kangaroo rats originally in population A are now to be considered as a new species. Which of the following best explains the mechanism that caused this speciation event in the giant kangaroo rats of population A?

The animals in population A were reproductively isolated from those in populations B, C, and D

In a certain small mammal, fur color is controlled by a pair of alleles, with � being dominant over �. The genotypes �� and �� result in dark-colored fur, the genotype bb results in light-colored fur. A population of the species has the following allele frequencies: �=0.85 and �=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?

The frequency of the B� allele will increase because light-colored individuals will be more visible to predators.

The researchers built an enclosure to prevent migration into and out of the O'Neill rock pocket mouse population for a period of two years. Which of the following best predicts the effect of the enclosure on the O'Neill population?

The frequency of the MC1RD��1�� allele will decline due to natural selection.

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?

The group of mice fed the mutagen will show a greater ability to digest the food, because the higher genetic variation within the group makes it more likely that some individuals will have a combination of genes better adapted to the new food.

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

The original habitat had many available unoccupied ecological niches that were colonized by populations of the original species.

Some plant species flower in response to increasing daily temperatures in the spring. Many of these species rely on pollinators that migrate based on changes in day length and the position of the Sun. The current global warming trend is placing new selective pressures on the species involved in these relationships. Which of the following best explains the impact of these new selective pressures on the organisms involved?

The plant species will flower earlier in the spring in response to rising temperatures before the arrival of the pollinators, so seeds will not be produced.

The researchers determined that the East lava flow population is not in Hardy-Weinberg equilibrium. Which of the following best explains why the population is not in Hardy-Weinberg equilibrium?

The presence of MC1Rd��1�� alleles in the East lava flow population is an indication of gene flow from mice populations living on light granite rocks.

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?

The two populations will show significant genetic differences because the founder effect will result in significant losses in diversity in the smaller population

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?

There is no difference in iridium levels in sediments that were deposited on Earth 3.6 billion years old, compared to recent sediments.