CThe dry mountain ranges of the western United States contain rocks dating back 440 to 510 million years, to the Ordovician period, and teeming with evidence of tropical marine life. This rock record provides clues about one of the most significant radiations (periods when existing life-forms gave rise to variations that would eventually evolve into entirely new species) in the history of marine invertebrates. During this radiation the number of marine biological families increased greatly, and these families included species that would dominate the marine ecosystems of the area for the next 215 million years. Although the radiation spanned tens of millions of years, major changes in many species occurred during a geologically short time span within the radiation and, furthermore, appear to have occurred worldwide, suggesting that external events were major factors in the radiation. And , in fact, there is evidence of major ecological and geological changes during this period: the sea level dropped drastically and mountain ranges were formed, in this instance, rather than leading to large-scale extinctions, these kinds of environmental changes may have resulted in an enriched pattern of habitats and nutrients, which in turn gave rise to the Ordovician radiation. However, the actual relationship between these environmental factors and the diversification of life forms is not yet fully understood.

The passage is primarily concerned with

The dry mountain ranges of the western United States contain rocks dating back 440 to 510 million years, to the Ordovician period, and teeming with evidence of tropical marine life. This rock record provides clues about one of the most significant radiations (periods when existing life-forms gave rise to variations that would eventually evolve into entirely new species) in the history of marine invertebrates. During this radiation the number of marine biological families increased greatly, and these families included species that would dominate the marine ecosystems of the area for the next 215 million years. Although the radiation spanned tens of millions of years, major changes in many species occurred during a geologically short time span within the radiation and, furthermore, appear to have occurred worldwide, suggesting that external events were major factors in the radiation. And , in fact, there is evidence of major ecological and geological changes during this period: the sea level dropped drastically and mountain ranges were formed, in this instance, rather than leading to large-scale extinctions, these kinds of environmental changes may have resulted in an enriched pattern of habitats and nutrients, which in turn gave rise to the Ordovician radiation. However, the actual relationship between these environmental factors and the diversification of life forms is not yet fully understood.

Which of the following can be inferred from the passage regarding the geologic changes that occurred during Ordovician period?

The dry mountain ranges of the western United States contain rocks dating back 440 to 510 million years, to the Ordovician period, and teeming with evidence of tropical marine life. This rock record provides clues about one of the most significant radiations (periods when existing life-forms gave rise to variations that would eventually evolve into entirely new species) in the history of marine invertebrates. During this radiation the number of marine biological families increased greatly, and these families included species that would dominate the marine ecosystems of the area for the next 215 million years. Although the radiation spanned tens of millions of years, major changes in many species occurred during a geologically short time span within the radiation and, furthermore, appear to have occurred worldwide, suggesting that external events were major factors in the radiation. And , in fact, there is evidence of major ecological and geological changes during this period: the sea level dropped drastically and mountain ranges were formed, in this instance, rather than leading to large-scale extinctions, these kinds of environmental changes may have resulted in an enriched pattern of habitats and nutrients, which in turn gave rise to the Ordovician radiation. However, the actual relationship between these environmental factors and the diversification of life forms is not yet fully understood.

Which of the following best describes the function of last sentence of the passage?

In 1994, a team of scientists led by David McKay began studying the meteorite ALH84001, which had been discovered in Antarctica in 1984. Two years later, the McKay team announced that ALH84001, which scientists generally agree originated on Mars, contained compelling evidence that life once existed on Mars. This evidence includes the discovery of organic molecules in ALH84001, the first ever found in Martian rock. Organic molecules—complex, carbon-based compounds— form the basis for terrestrial life. The organic molecules found in ALH84001 are poly cyclic aromatic hydrocarbons, or PAHs. When microbes die, their organic material often decays into PAHs.

Skepticism about the McKay team’s claim remains, however. For example, ALH84001 has been on Earth for 13,000 years, suggesting to some scientists that its PAHs might have resulted from terrestrial contamination. However, McKay’s team has demonstrated that the concentration of PAHs increases as one looks deeper into ALH84001, contrary to what one would expect from terrestrial contamination. The skeptics’ strongest argument, however, is that processes unrelated to organic life can easily produce all the evidence found by McKay’s team, including PAHs. For example, star formation produces PAHs. Moreover, PAHs frequently appear in other meteorites, and no one attributes their presence to life processes. Yet McKay’s team notes that the particular combination of PAHs in ALH84001 is more similar to the combinations produced by decaying organisms than to those originating from non biological processes.

The primary purpose of the passage is to

CIn 1994, a team of scientists led by David McKay began studying the meteorite ALH84001, which had been discovered in Antarctica in 1984. Two years later, the McKay team announced that ALH84001, which scientists generally agree originated on Mars, contained compelling evidence that life once existed on Mars. This evidence includes the discovery of organic molecules in ALH84001, the first ever found in Martian rock. Organic molecules—complex, carbon-based compounds— form the basis for terrestrial life. The organic molecules found in ALH84001 are poly cyclic aromatic hydrocarbons, or PAHs. When microbes die, their organic material often decays into PAHs.

Skepticism about the McKay team’s claim remains, however. For example, ALH84001 has been on Earth for 13,000 years, suggesting to some scientists that its PAHs might have resulted from terrestrial contamination. However, McKay’s team has demonstrated that the concentration of PAHs increases as one looks deeper into ALH84001, contrary to what one would expect from terrestrial contamination. The skeptics’ strongest argument, however, is that processes unrelated to organic life can easily produce all the evidence found by McKay’s team, including PAHs. For example, star formation produces PAHs. Moreover, PAHs frequently appear in other meteorites, and no one attributes their presence to life processes. Yet McKay’s team notes that the particular combination of PAHs in ALH84001 is more similar to the combinations produced by decaying organisms than to those originating from non biological processes.

The passage asserts which of the following about the claim that ALH84001 originated on Mars?

In 1994, a team of scientists led by David McKay began studying the meteorite ALH84001, which had been discovered in Antarctica in 1984. Two years later, the McKay team announced that ALH84001, which scientists generally agree originated on Mars, contained compelling evidence that life once existed on Mars. This evidence includes the discovery of organic molecules in ALH84001, the first ever found in Martian rock. Organic molecules—complex, carbon-based compounds— form the basis for terrestrial life. The organic molecules found in ALH84001 are poly cyclic aromatic hydrocarbons, or PAHs. When microbes die, their organic material often decays into PAHs.

Skepticism about the McKay team’s claim remains, however. For example, ALH84001 has been on Earth for 13,000 years, suggesting to some scientists that its PAHs might have resulted from terrestrial contamination. However, McKay’s team has demonstrated that the concentration of PAHs increases as one looks deeper into ALH84001, contrary to what one would expect from terrestrial contamination. The skeptics’ strongest argument, however, is that processes unrelated to organic life can easily produce all the evidence found by McKay’s team, including PAHs. For example, star formation produces PAHs. Moreover, PAHs frequently appear in other meteorites, and no one attributes their presence to life processes. Yet McKay’s team notes that the particular combination of PAHs in ALH84001 is more similar to the combinations produced by decaying organisms than to those originating from non biological processes.

The passage suggests that the fact that ALH84001 has been on Earth for 13,000 years has been used by some scientists to support which of the following claims about ALH84001?

In 1994, a team of scientists led by David McKay began studying the meteorite ALH84001, which had been discovered in Antarctica in 1984. Two years later, the McKay team announced that ALH84001, which scientists generally agree originated on Mars, contained compelling evidence that life once existed on Mars. This evidence includes the discovery of organic molecules in ALH84001, the first ever found in Martian rock. Organic molecules—complex, carbon-based compounds— form the basis for terrestrial life. The organic molecules found in ALH84001 are poly cyclic aromatic hydrocarbons, or PAHs. When microbes die, their organic material often decays into PAHs.

Skepticism about the McKay team’s claim remains, however. For example, ALH84001 has been on Earth for 13,000 years, suggesting to some scientists that its PAHs might have resulted from terrestrial contamination. However, McKay’s team has demonstrated that the concentration of PAHs increases as one looks deeper into ALH84001, contrary to what one would expect from terrestrial contamination. The skeptics’ strongest argument, however, is that processes unrelated to organic life can easily produce all the evidence found by McKay’s team, including PAHs. For example, star formation produces PAHs. Moreover, PAHs frequently appear in other meteorites, and no one attributes their presence to life processes. Yet McKay’s team notes that the particular combination of PAHs in ALH84001 is more similar to the combinations produced by decaying organisms than to those originating from non biological processes.

The passage suggests that if a meteorite contained PAHs that were the result of terrestrial contamination, then one would expect which of the following to be true?

In 1994, a team of scientists led by David McKay began studying the meteorite ALH84001, which had been discovered in Antarctica in 1984. Two years later, the McKay team announced that ALH84001, which scientists generally agree originated on Mars, contained compelling evidence that life once existed on Mars. This evidence includes the discovery of organic molecules in ALH84001, the first ever found in Martian rock. Organic molecules—complex, carbon-based compounds— form the basis for terrestrial life. The organic molecules found in ALH84001 are poly cyclic aromatic hydrocarbons, or PAHs. When microbes die, their organic material often decays into PAHs.

Skepticism about the McKay team’s claim remains, however. For example, ALH84001 has been on Earth for 13,000 years, suggesting to some scientists that its PAHs might have resulted from terrestrial contamination. However, McKay’s team has demonstrated that the concentration of PAHs increases as one looks deeper into ALH84001, contrary to what one would expect from terrestrial contamination. The skeptics’ strongest argument, however, is that processes unrelated to organic life can easily produce all the evidence found by McKay’s team, including PAHs. For example, star formation produces PAHs. Moreover, PAHs frequently appear in other meteorites, and no one attributes their presence to life processes. Yet McKay’s team notes that the particular combination of PAHs in ALH84001 is more similar to the combinations produced by decaying organisms than to those originating from non biological processes.

Which of the following best describes the function of the last sentence of the first paragraph?

In 1994, a team of scientists led by David McKay began studying the meteorite ALH84001, which had been discovered in Antarctica in 1984. Two years later, the McKay team announced that ALH84001, which scientists generally agree originated on Mars, contained compelling evidence that life once existed on Mars. This evidence includes the discovery of organic molecules in ALH84001, the first ever found in Martian rock. Organic molecules—complex, carbon-based compounds— form the basis for terrestrial life. The organic molecules found in ALH84001 are poly cyclic aromatic hydrocarbons, or PAHs. When microbes die, their organic material often decays into PAHs.

Skepticism about the McKay team’s claim remains, however. For example, ALH84001 has been on Earth for 13,000 years, suggesting to some scientists that its PAHs might have resulted from terrestrial contamination. However, McKay’s team has demonstrated that the concentration of PAHs increases as one looks deeper into ALH84001, contrary to what one would expect from terrestrial contamination. The skeptics’ strongest argument, however, is that processes unrelated to organic life can easily produce all the evidence found by McKay’s team, including PAHs. For example, star formation produces PAHs. Moreover, PAHs frequently appear in other meteorites, and no one attributes their presence to life processes. Yet McKay’s team notes that the particular combination of PAHs in ALH84001 is more similar to the combinations produced by decaying organisms than to those originating from non biological processes.

The passage suggests that McKay’s team would agree with which of the following regarding the PAHs produced by non organic processes?

Numerous investigations have been made to test the validity of the theory that facial behaviors associated with emotions are universal. Proponents exist for both sides, with some postulating universals in emotional facial behavior while others arguing against such a possibility.

A team of sociologists studied these contradictory views and hypothesized that the universals are to be discovered in the relationship between different patterns of facial muscles and specific emotions such as happiness, sadness, anger, and fear. These sociologists tried to find evidence for their hypothesis by conducting experiments in which they showed photographs of Western faces to subjects from various cultures in order to determine whether the same facial behavior would be judged as the same emotion, irrespective of the observer’s culture. College educated subjects from countries such as Argentina, Chile, the U.S., and Japan were chosen to identify the same faces with the same emotion words as were the members of two pre-literature cultures. They interpreted the results of the experiments as evidence of universals in facial behavior. However, it is arguable as to how uncontaminated these experiments were. The problem was that all the subjects, even those from the pre-literature societies, came from cultures that had had exposure to some of the same mass media portrayals of facial behavior in Western cultures. This handicap was successfully addressed in a subsequent study by the team in which only subjects who met the criteria established to screen out all but those who had minimal opportunity to learn or imitate or even recognize uniquely Western facial behaviors were chosen to participate in the experiment. The results conclusively supported the hypothesis that specific facial behaviors are associated with specific emotions across various cultures.

However, the increasing evidence of a pan-cultural element in emotional facial behavior does not suggest a lack of cultural differences in emotional expression. These differences manifest themselves in the circumstances that elicit an emotion, with the same emotion being preceded by different stimuli across cultures.

Which of the following statements would the author most likely agree with?

Numerous investigations have been made to test the validity of the theory that facial behaviors associated with emotions are universal. Proponents exist for both sides, with some postulating universals in emotional facial behavior while others arguing against such a possibility.

A team of sociologists studied these contradictory views and hypothesized that the universals are to be discovered in the relationship between different patterns of facial muscles and specific emotions such as happiness, sadness, anger, and fear. These sociologists tried to find evidence for their hypothesis by conducting experiments in which they showed photographs of Western faces to subjects from various cultures in order to determine whether the same facial behavior would be judged as the same emotion, irrespective of the observer’s culture. College educated subjects from countries such as Argentina, Chile, the U.S., and Japan were chosen to identify the same faces with the same emotion words as were the members of two pre-literature cultures. They interpreted the results of the experiments as evidence of universals in facial behavior. However, it is arguable as to how uncontaminated these experiments were. The problem was that all the subjects, even those from the pre-literature societies, came from cultures that had had exposure to some of the same mass media portrayals of facial behavior in Western cultures. This handicap was successfully addressed in a subsequent study by the team in which only subjects who met the criteria established to screen out all but those who had minimal opportunity to learn or imitate or even recognize uniquely Western facial behaviors were chosen to participate in the experiment. The results conclusively supported the hypothesis that specific facial behaviors are associated with specific emotions across various cultures.

However, the increasing evidence of a pan-cultural element in emotional facial behavior does not suggest a lack of cultural differences in emotional expression. These differences manifest themselves in the circumstances that elicit an emotion, with the same emotion being preceded by different stimuli across cultures.

The author is primarily concerned with

Numerous investigations have been made to test the validity of the theory that facial behaviors associated with emotions are universal. Proponents exist for both sides, with some postulating universals in emotional facial behavior while others arguing against such a possibility.

A team of sociologists studied these contradictory views and hypothesized that the universals are to be discovered in the relationship between different patterns of facial muscles and specific emotions such as happiness, sadness, anger, and fear. These sociologists tried to find evidence for their hypothesis by conducting experiments in which they showed photographs of Western faces to subjects from various cultures in order to determine whether the same facial behavior would be judged as the same emotion, irrespective of the observer’s culture. College educated subjects from countries such as Argentina, Chile, the U.S., and Japan were chosen to identify the same faces with the same emotion words as were the members of two pre-literature cultures. They interpreted the results of the experiments as evidence of universals in facial behavior. However, it is arguable as to how uncontaminated these experiments were. The problem was that all the subjects, even those from the pre-literature societies, came from cultures that had had exposure to some of the same mass media portrayals of facial behavior in Western cultures. This handicap was successfully addressed in a subsequent study by the team in which only subjects who met the criteria established to screen out all but those who had minimal opportunity to learn or imitate or even recognize uniquely Western facial behaviors were chosen to participate in the experiment. The results conclusively supported the hypothesis that specific facial behaviors are associated with specific emotions across various cultures.

However, the increasing evidence of a pan-cultural element in emotional facial behavior does not suggest a lack of cultural differences in emotional expression. These differences manifest themselves in the circumstances that elicit an emotion, with the same emotion being preceded by different stimuli across cultures.

Which of the following most aptly describes the function of the final paragraph?

Numerous investigations have been made to test the validity of the theory that facial behaviors associated with emotions are universal. Proponents exist for both sides, with some postulating universals in emotional facial behavior while others arguing against such a possibility.

A team of sociologists studied these contradictory views and hypothesized that the universals are to be discovered in the relationship between different patterns of facial muscles and specific emotions such as happiness, sadness, anger, and fear. These sociologists tried to find evidence for their hypothesis by conducting experiments in which they showed photographs of Western faces to subjects from various cultures in order to determine whether the same facial behavior would be judged as the same emotion, irrespective of the observer’s culture. College educated subjects from countries such as Argentina, Chile, the U.S., and Japan were chosen to identify the same faces with the same emotion words as were the members of two pre-literature cultures. They interpreted the results of the experiments as evidence of universals in facial behavior. However, it is arguable as to how uncontaminated these experiments were. The problem was that all the subjects, even those from the pre-literature societies, came from cultures that had had exposure to some of the same mass media portrayals of facial behavior in Western cultures. This handicap was successfully addressed in a subsequent study by the team in which only subjects who met the criteria established to screen out all but those who had minimal opportunity to learn or imitate or even recognize uniquely Western facial behaviors were chosen to participate in the experiment. The results conclusively supported the hypothesis that specific facial behaviors are associated with specific emotions across various cultures.

However, the increasing evidence of a pan-cultural element in emotional facial behavior does not suggest a lack of cultural differences in emotional expression. These differences manifest themselves in the circumstances that elicit an emotion, with the same emotion being preceded by different stimuli across cultures.

Which of the following is mentioned in the passage?