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In the 17th century, scientists were just beginning to understand the circulatory system of the heart. The two following viewpoints are the two most popular theories of the day.
Scientist I The heart pumps blood through arteries and veins but the two systems are separate. They are similar, just as the senses of smell and taste are when observing food, but ultimately they are two separate systems which perform separate functions. Hot blood flows from the heart, through the arteries, and to the organs which consume the blood much as a human would consume nourishment to survive. Venous blood originates in the liver and follows the veins to the organs where it is similarly consumed.
Scientist II The arteries and veins are two parts of one system. Blood flows from the heart, around the body, and back into the heart through the veins like two sets of one way streets. The idea of two systems, each pumping blood to the organs is unreasonable. If the heart can pump 6 oz of blood per minute, then the liver would have to produce 540 pounds of blood per day. A simple measurement of a human’s weight shows how unlikely that solution is. The single circulatory system is far superior as it explains the function of the heart, the arteries, and the veins clearly.
Why does Scientist I compare the arteries and veins to smell and taste?
To illustrate another example of systems that are linked but are not the same.
Because blood has a very distinct odor and taste.
A person with liver issues will produce blood that tastes and smells different.
The senses of taste and smell are the strongest.
Explanation
The scientist is trying to make a comparison that the reader will already have experience with, as he is suggesting that the two systems are similar and yet different.
The chart above shows the height growth of three different plant species after a period of 2 weeks. Each plant species was grown in 4 different soil mediums. All the plants were grown in the same environment with equal amounts of light, water, and oxygen.
Based on the chart above, which plant species was consistently taller than the other plant species regardless of soil medium?
Plant 3
Plant 2
Plant 1
This information cannot be determined.
All three plants grew at equally consistent heights.
Explanation
After reading the chart, it is clear that Plant 3 was taller than Plant 1 and Plant 2 at every measurement point.
A mycologist performed an experiment to determine the effect of methanol on the mold Neurospora crassa.
1,500 Neurospora spores were divided evenly into five groups of three large glass test tubes each. Then each test tube was filled with 5.0 mL of liquid nutrient solution and either 0 mL, 0.5 mL, 1.0 mL, 1.5 mL, or 2.0 mL of methanol. The tubes were placed in an incubator at 28oC overnight to germinate, and then their aerial growth was marked beginning the next morning and every twelve hours thereafter for two days.
Table 1 shows the average growth data with 
In general, the results of the study suggest that Neurospora cultures prepared in liquid media can tolerate at least how many milliliters of methanol and still grow?
Explanation
Table 1 shows that the mold cultures still grow when 0.5 mL, 1.0 mL, or 1.5 mL methanol is added. The cultures do not grow when 2.0 mL of methanol is added. Therefore, the study suggests that the largest amount of methanol that the strains can tolerate is 1.5 mL.
Sleep plays a vital role in defining the daily activities of virtually all animals. During periods of sleep, the parasympathetic nervous system becomes active and induces a relaxed state in response to increased levels of the hormone melatonin. Yet, despite its ubiquity in the animal kingdom, the purpose of sleep and its role in our daily lives has been disputed by scientists. Two scientists discuss their theories about the purpose of sleep.
Scientist 1
During periods of sleep, animals are able to conserve energy that they would otherwise be spending on unnecessary activity. If an animal’s primary food source is most abundant during daylight, it is a waste of precious energy to be moving about at night. For example, many herbivores, such as squirrels, are diurnal (sleep during the night) because their food source is available during the day, while many insectivores, such as bats, are nocturnal (sleep during the day) because their food source is available during the night. Food sources, as an animal’s most valuable resource, dictate their sleep cycles. Many animal traits observable today evolved as a result of the supply and demand of food in their natural habitat.
Scientist 2
During waking hours, it is true that the body utilizes large amounts of energy. However, the role of sleep is to restore biological products that were utilized during periods of wakefulness, rather than simply avoid utilizing energy in the first place. Many types of biological molecules, such as hormones, are released throughout the body while an animal is active. Sleep serves as a period of inactivity during which the body can manufacture and store a supply of these molecules for future use during the next period of activity. Furthermore, sleep allows the body to repair cellular damages that has accumulated during waking hours. Experimental evidence shows that when animals are deprived of sleep, their immune system quickly weakens and death rates increase. Sleep is necessary for animals to prevent accumulation of damage and to regenerate crucial biomolecules for daily life.
Both scientists give evidence to support their theories. The evidence given by Scientist 1 can best be described as __________.
observational
quantitative
empirical
experimental
natural
Explanation
Scientist 1 gives two examples of animals that appear to follow the trends of his theory. "For example, many herbivores, such as squirrels, are diurnal . . . while many insectivores, such as bats, are nocturnal"
This evidence is strictly observational. There is no experimental set-up, quantitative or empirical data. Though the evidence is observation of animals in their natural state, observational is a commonly used classification of evidence, while natural is not, making observational the best answer choice.
Sleep plays a vital role in defining the daily activities of virtually all animals. During periods of sleep, the parasympathetic nervous system becomes active and induces a relaxed state in response to increased levels of the hormone melatonin. Despite its ubiquity in the animal kingdom, the purpose of sleep and its role in our daily lives has been disputed by scientists. Two scientists discuss their theories about the purpose of sleep.
Scientist 1
During periods of sleep, animals are able to conserve energy that they would otherwise be spending on unnecessary activity. If an animal’s primary food source is most abundant during daylight, it is a waste of precious energy to be moving about at night. For example, many herbivores, such as squirrels, are diurnal (sleep during the night) because their food source is available during the day, while many insectivores, such as bats, are nocturnal (sleep during the day) because their food source is available during the night. Food sources, as an animal’s most valuable resource, dictate their sleep cycles. Many animal traits observable today evolved as a result of the supply and demand of food in their natural habitat.
Scientist 2
During waking hours, it is true that the body utilizes large amounts of energy; however, the role of sleep is to restore biological products that were utilized during periods of wakefulness, rather than simply to avoid utilizing energy in the first place. Many types of biological molecules, such as hormones, are released throughout the body while an animal is active. Sleep serves as a period of inactivity, during which the body can manufacture and store a supply of these molecules for future use during the next period of activity. Furthermore, sleep allows the body to repair cellular damages that has accumulated during waking hours. Experimental evidence shows that when animals are deprived of sleep, their immune system quickly weakens and death rates increase. Sleep is necessary for animals to prevent accumulation of damage and to regenerate crucial biomolecules for daily life.
Scientist 1’s theory would be most weakened if which of the following were true?
Sharks continue to move constantly while sleeping.
Some herbivores are diurnal, while others are nocturnal.
Desert animals often spend long periods sleeping during the day.
When deprived of sleep, chimpanzees require more food.
Bees sleep less during spring, when food is abundant.
Explanation
The answer is "Sharks continue to move constantly while sleeping" because Scientist 1 argues that one reason we sleep is because moving around at night wastes energy. Thus, we sleep to conserve energy. If sharks expend energy even while sleeping, this would contradict Scientist 1.
When deprived of sleep, chimpanzees would expend more energy at night and require more, not less, food. During spring, when food for bees is abundant, the bees would be able to gain more energy and sleep less, not more.
A mycologist performed an experiment to determine the effect of methanol on the mold Neurospora crassa.
1,500 Neurospora spores were divided evenly into five groups of three large glass test tubes each. Then each test tube was filled with 5.0 mL of liquid nutrient solution and either 0 mL, 0.5 mL, 1.0 mL, 1.5 mL, or 2.0 mL of methanol. The tubes were placed in an incubator at 28oC overnight to germinate, and then their aerial growth was marked beginning the next morning and every twelve hours thereafter for two days.
Table 1 shows the average growth data with
In general, the results of the study suggest that Neurospora cultures prepared in liquid media can tolerate at least how many milliliters of methanol and still grow?
Explanation
Table 1 shows that the mold cultures still grow when 0.5 mL, 1.0 mL, or 1.5 mL methanol is added. The cultures do not grow when 2.0 mL of methanol is added. Therefore, the study suggests that the largest amount of methanol that the strains can tolerate is 1.5 mL.
In the 17th century, scientists were just beginning to understand the circulatory system of the heart. The two following viewpoints are the two most popular theories of the day.
Scientist I The heart pumps blood through arteries and veins but the two systems are separate. They are similar, just as the senses of smell and taste are when observing food, but ultimately they are two separate systems which perform separate functions. Hot blood flows from the heart, through the arteries, and to the organs which consume the blood much as a human would consume nourishment to survive. Venous blood originates in the liver and follows the veins to the organs where it is similarly consumed.
Scientist II The arteries and veins are two parts of one system. Blood flows from the heart, around the body, and back into the heart through the veins like two sets of one way streets. The idea of two systems, each pumping blood to the organs is unreasonable. If the heart can pump 6 oz of blood per minute, then the liver would have to produce 540 pounds of blood per day. A simple measurement of a human’s weight shows how unlikely that solution is. The single circulatory system is far superior as it explains the function of the heart, the arteries, and the veins clearly.
Why does Scientist I compare the arteries and veins to smell and taste?
To illustrate another example of systems that are linked but are not the same.
Because blood has a very distinct odor and taste.
A person with liver issues will produce blood that tastes and smells different.
The senses of taste and smell are the strongest.
Explanation
The scientist is trying to make a comparison that the reader will already have experience with, as he is suggesting that the two systems are similar and yet different.
Sleep plays a vital role in defining the daily activities of virtually all animals. During periods of sleep, the parasympathetic nervous system becomes active and induces a relaxed state in response to increased levels of the hormone melatonin. Despite its ubiquity in the animal kingdom, the purpose of sleep and its role in our daily lives has been disputed by scientists. Two scientists discuss their theories about the purpose of sleep.
Scientist 1
During periods of sleep, animals are able to conserve energy that they would otherwise be spending on unnecessary activity. If an animal’s primary food source is most abundant during daylight, it is a waste of precious energy to be moving about at night. For example, many herbivores, such as squirrels, are diurnal (sleep during the night) because their food source is available during the day, while many insectivores, such as bats, are nocturnal (sleep during the day) because their food source is available during the night. Food sources, as an animal’s most valuable resource, dictate their sleep cycles. Many animal traits observable today evolved as a result of the supply and demand of food in their natural habitat.
Scientist 2
During waking hours, it is true that the body utilizes large amounts of energy; however, the role of sleep is to restore biological products that were utilized during periods of wakefulness, rather than simply to avoid utilizing energy in the first place. Many types of biological molecules, such as hormones, are released throughout the body while an animal is active. Sleep serves as a period of inactivity, during which the body can manufacture and store a supply of these molecules for future use during the next period of activity. Furthermore, sleep allows the body to repair cellular damages that has accumulated during waking hours. Experimental evidence shows that when animals are deprived of sleep, their immune system quickly weakens and death rates increase. Sleep is necessary for animals to prevent accumulation of damage and to regenerate crucial biomolecules for daily life.
Scientist 1’s theory would be most weakened if which of the following were true?
Sharks continue to move constantly while sleeping.
Some herbivores are diurnal, while others are nocturnal.
Desert animals often spend long periods sleeping during the day.
When deprived of sleep, chimpanzees require more food.
Bees sleep less during spring, when food is abundant.
Explanation
The answer is "Sharks continue to move constantly while sleeping" because Scientist 1 argues that one reason we sleep is because moving around at night wastes energy. Thus, we sleep to conserve energy. If sharks expend energy even while sleeping, this would contradict Scientist 1.
When deprived of sleep, chimpanzees would expend more energy at night and require more, not less, food. During spring, when food for bees is abundant, the bees would be able to gain more energy and sleep less, not more.
Sleep plays a vital role in defining the daily activities of virtually all animals. During periods of sleep, the parasympathetic nervous system becomes active and induces a relaxed state in response to increased levels of the hormone melatonin. Despite its ubiquity in the animal kingdom, the purpose of sleep and its role in our daily lives has been disputed by scientists. Two scientists discuss their theories about the purpose of sleep.
Scientist 1
During periods of sleep, animals are able to conserve energy that they would otherwise be spending on unnecessary activity. If an animal’s primary food source is most abundant during daylight, it is a waste of precious energy to be moving about at night. For example, many herbivores, such as squirrels, are diurnal (asleep during the night) because their food source is available during the day, while many insectivores, such as bats, are nocturnal (asleep during the day) because their food source is available during the night. Food sources, as an animal’s most valuable resource, dictate their sleep cycles. Many animal traits observable today evolved as a result of the supply and demand of food in their natural habitat.
Scientist 2
During waking hours, it is true that the body utilizes large amounts of energy; however, the role of sleep is to restore biological products that were utilized during periods of wakefulness, rather than simply to avoid utilizing energy in the first place. Many types of biological molecules, such as hormones, are released throughout the body while an animal is active. Sleep serves as a period of inactivity during which the body can manufacture and store a supply of these molecules, for future use during the next period of activity; furthermore, sleep allows the body to repair cellular damage that has accumulated during waking hours. Experimental evidence shows that when animals are deprived of sleep, their immune system quickly weakens and death rates increase. Sleep is necessary for animals to prevent accumulation of damage and to regenerate crucial biomolecules for daily life.
Studies have shown that students who sleep well the night before an exam receive better marks. Why might this be, according to the hypotheses of both scientists?
Students who sleep more have more energy and restored molecular balance.
Students who sleep less are less alert.
Students who sleep more have a better diet.
Students who sleep less start to become nocturnal.
Students who sleep more have better study habits.
Explanation
This question combines the two passage theories. "Students who sleep more have more energy and restored molecular balance" is the best answer because it reflects the viewpoints of both scientists.
A group of scientists wanted to test the effects of Nitra-Grow, a chemical additive that can be given to plants to help them grow. 3 test groups of plants were given all the same time of sunlight, the same type of soil, and the same amount of water. Plant A was given no extra chemicals. Plant B was given 5g of Nitra-Grow. Plant C was given 5g of Ammonia to see if Nitra-Grow worked any better than a basic nitrogen-based household product. The plants are then measured on 5 consecutive days to find their average height (in cm).
| DAY | Height Plant A (cm) | Height Plant B (cm) | Height Plant C (cm) |
|---|---|---|---|
| 1 | 1.2 | 1.2 | 1.2 |
| 2 | 1.4 | 1.4 | 1.2 |
| 3 | 1.6 | 1.8 | 1.3 |
| 4 | 1.8 | 2.4 | 1.3 |
| 5 | 2.0 | 2.6 | 1.4 |
What is the general relationship between plant height and the amount of days?
As time increases, the plant height increases.
As time increases, the plant height increases, then decreases.
As the plant height increases, the time increases.
As the plant height increases, the time decreases.
There is no relationship between time and height of the plants.
Explanation
As time increases, the heights of all plants increase (except for plant B on day 6). The day doesn't change just because the plants grow.