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Set 1NORTH AMERICAN GRASSLANDS1.In North America, native grasslands occur primarily in the Great Plains in the middle of the continent. The North American prairie biome is one of the most extensive grasslands in the world, extending from the edge of the Rocky Mountains in the west to the deciduous forest in the east, and from northern Mexico in the south to Canada in the north. Average annual rainfall ranges from about 40 cm (16 inches) in the west to 80 cm (31 inches) in the east. Average annual temperatures range between 10 degrees and 20 degrees Celsius (50 to 68 degrees Fahrenheit). In the moist regions of the North American grasslands, especially in the northern Great Plains, rainfall is distinctly seasonal, and temperatures can vary widely from very hot in summer to bitter cold in winter.2.One hundred years ago, the Great Plains grasslands were one vast, unbroken prairie. Much of the prairie is now farmland, the most productive agricultural region in the world, dominated by monocultures of cereal grains. Wheat, barley, soybeans, corn, and sunflowers occupy the land that was once prairie. In areas given over to grazing lands for cattle and sheep, virtually all the major native grasses have been replaced by alien species.3.An important feature of the northern Great Plains grasslands is the presence of millions of glacial depressions that are now small ponds known as prairie potholes. They were formed during the most recent Ice Age, when streams flowed in tunnels beneath glacially formed sandy ridges. When the Ice Age ended around 12,000 years ago, the retreating glaciers created about 25 million depressions across a 300,000-square-mile landscape—about 83 potholes per square mile. As the ice blocks melted, much of the water was left behind, forming wetlands ranging in size from a tenth of an acre to several acres. The wetlands were soon surrounded by fluttering waves of grasses: shortgrass, mixed grass, and tallgrass.4.Today these small wetlands still cover the prairies, although much of the landscape— including both native grasses and potholes—has been transformed to cropland and grassland for grazing. What does remain of the wetlands, however, still serves as an important breeding area for more than 300 bird species, including large numbers of migrating shorebirds and waterfowl. The potholes fill up with water during spring rains and usually dry out by late summer. Every spring, birds arrive in great numbers—northern pintails, mallards, coots, and pied-billed grebes—4 to 6 million strong, to mate in the seasonal wetlands that dot portions of Minnesota, Iowa, North and South Dakota, Montana, Alberta, Saskatchewan, and Manitoba. Prairie pothole country produces half of North America’s 35 to 40 million ducks and is renowned worldwide as a "duck factory."5.Recently biologists have discovered that the prairie pothole region is potentially a vast carbon sink: a natural sponge that absorbs carbon dioxide emissions from cars, factories, and power plants. Carbon dioxide is the most common of all the pollutants acting as greenhouse gases that heat up the atmosphere. Fortunately, however, carbon dioxide is captured naturally and stored in trees, soil, and plants. Scientists have termed this "carbon sequestration." They have determined that prairie potholes hold an average of 2.5 tons of carbon per acre per year when not being farmed. This means that if the entire pothole region in the United States and Canada were to stop being farmed, the region would store about 400 million tons of carbon over 10 years—the equivalent of taking almost 4 million cars off the road. Thus, preserving the potholes could be a way to offset greenhouse gas emissions that are warming the planet.Glossary:biome: one of the world’s major natural communities, classified by predominant vegetationmonoculture: cultivation of large land areas with a single plant variety The word alien in paragraph 2 is closest in meaning to ().

A. healthy
B. simple
C. cheaper
D. imported

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Set 4THE TRICKSTER FIGURE IN MYTHOLOGY1.In the study of mythology, the character known as the trickster is a god, spirit, human, or animal who breaks the rules of the gods or nature, sometimes maliciously but usually with results that are positive. The rule breaking often takes the form of mischief or thievery. The trickster is usually male but occasionally disguises himself in female form. He can be cunning or foolish, or both, and often very humorous. His curiosity leads him into trouble, but he rescues himself with his sly wit. When he plays tricks, he performs important cultural tasks that benefit humans, and for this reason the trickster is a significant figure in world mythology.2.In different cultures, the trickster and the hero are combined in various ways. In Greek mythology, Prometheus steals fire from the gods and gives it to humans, a feat making him more of a hero than a trickster, and he is usually portrayed as an intellectual. In many Native American stories, Coyote also steals fire from the gods, but Coyote is usually more of a jokester or a prankster than an intellectual.3.The trickster is both creator and destroyer, giver and taker, one who tricks others and is tricked in return. The pranks of the trickster are compulsive and uncontrollable. He does not act consciously; he acts out of passion and impulse. He knows neither good nor evil, yet he is responsible for both. He possesses no morals, yet through his behavior morality comes into being. According to psychologist Carl Jung, the trickster is "a primitive cosmic being of divine-animal nature, on the one hand superior to man because of his superhuman qualities, and on the other hand inferior to him because of his unreason and unconsciousness."4.In Native American mythology, the majority of trickster myths concern the creation or transformation of the earth. Such stories have a trickster who is always wandering, who is always hungry, who is not guided by normal ideas of good and evil, and who possesses some magical powers. In some stories he is a deity, and in others he is an animal or human subject to death. Several of these myths feature Raven or Coyote as the trickster-hero.5.In many creation myths of the Pacific Northwest, Raven illustrates the transformational nature of tricksters. Raven is the greatest shapeshifter of all and can change into anything to get what he wants. In one story, there is darkness at the beginning of the world, so Raven decides he will find light. He flies far from the earth, searching in the darkness, until he spots a glimmer of light coming from a window in the house of the gods. Raven knows the gods are protective of their possessions, so he devises a trick. He perches on a pine branch next to the house and watches each day as the chief god’s daughter draws water from a nearby lake. He magically transforms himself into a pinyon seed and falls into the girl’s drinking cup. The girl swallows the seed, which grows within her body, and she eventually gives birth to a boy. The child delights his grandparents, and his laughter tricks the elder gods into revealing where they hide a shining ball of light. The gods give the child the ball to play with, and then Raven transforms back to a bird and flies off carrying the ball of light in his beak. He hangs the ball-the sun-in the sky, bringing light to the world.6.Coyote’s character is similar to that of Raven’s, and both appear in stories carrying out similar roles. In several stories from the American Southwest, Coyote steals fire from a group of "fire beings" and gives it to humans. In some tales Coyote wants to make human life more interesting, so he introduces sickness, sorrow, and death. He often teaches through negative example by employing the human vices of lying, cheating, and stealing. His tricks often bring about destructive natural phenomena, such as a great flood that destroys the earth. However, by causing the flood, Coyote leads the human race to a new and better world. Coyote shows us that at the heart of the trickster is a savior whose great gift to humans is showing them new ways of knowing and doing.Glossary:mischief: tendency to play tricks or cause minor troublemischief: the act of theft; stealingpinyon seed: the seed of a pine tree; pine nut Select the appropriate phrases from the answer choices and match them to the trickster that they describe. TWO of the answer choices will NOT be used.This question is worth 3 points.Answer ChoicesA. Introduces sickness, sorrow, and death to make life more interestingB. Transforms into various shapes to achieve his purposesC. Appears as an intellectual hero in stories of good and evilD. Creates a ball of silver light that becomes the moonE. Changes into a seed to gain entrance to the house of the godsF. Causes a great flood and then leads humans to a better worldG. Brings light to the world by playing a trick on the godsRayon·____________________________________________________________·____________________________________________________________·____________________________________________________________

Set 3THE SENSE OF SMELL1.Smell is the most direct of all the senses. It is thought to be the oldest sense in terms of human evolution, which may explain why smell is hard-wired into the brain. The olfactory nerve, which manages the perception of smells, is essentially an extension of the brain. The olfactory nerve provides a direct link from receptors at the top of the nose to the portion of the brain that controls memory, emotion, and behavior.2.The olfactory system detects certain airborne chemicals that enter the nose and then transmits this chemical information to the limbic system in the brain. The olfactory region at the upper end of each nostril is yellow, moist, and full of fatty substances. The shade of yellow indicates the strength of the sense of smell: the deeper the shade, the keener and more acute it is. Animals have a very strong sense of smell, so their olfactory regions are dark yellow to reddish brown, while those of humans are light yellow.3.When an odorous substance enters the nose, it binds to olfactory receptor cells, the neurons lining the yellow upper portion of the nasal cavity. Olfactory receptor cells contain microscopic hairs called cilia that extend into the layer of mucus coating the inside of the nose. Odor molecules diffuse into this region and are absorbed by the cilia of the olfactory receptor cells. What this means is that when we hold a rose to our nose and inhale, odor molecules float up into the nasal cavity, where they are absorbed by five million olfactory receptor cells. The receptor cells alert the olfactory nerve, which sends impulses to the brain’s olfactory bulb, or smell center. Thus, olfactory information about the rose enters the brain’s limbic system, where, in most of us, it stimulates a feeling of pleasure.4.The limbic system of the brain integrates memory, emotion, and behavior. The system is composed of a group of related nervous system structures that are the functional center of emotions such as anger, fear, pleasure, and sadness. The components of the limbic system are linked to the cerebral cortex, the part of the brain involved in complex learning, reasoning, and personality. The cerebral cortex makes decisions about the emotional content of these unique human qualities after "consulting" the limbic system and other brain centers in processing and retrieving memories. It may, in turn, use memories to modify behavior.5.Scent may be the strongest trigger of memory and emotions. When we inhale a scent, receptors in the brain’s limbic center compare the odor entering our nose to odors stored in our memory. Along the way, memories associated with those odors are stimulated. A smell can be overwhelmingly nostalgic because it triggers powerful images and emotions. The waxy fragrance of crayons can instantly transport us to our second-grade classroom, or the scent of freshly mown grass can flood us with the joy of summer freedom. What we see and hear may fade quickly in short-term memory, but what we smell is sent directly to long-term memory.6.Smells can increase alertness and stimulate learning and retention. In one study, children memorized a word list, which was presented both with and without accompanying scents. The children recalled words on the list more easily and with higher accuracy when the list was given with scents than without, showing the link between smell and the ability to retain information. In another study, researchers examined how various smells can increase alertness and decrease stress. They found that the scent of lavender could wake up the metabolism and make people more alert. They also found that the smell of spiced apples could reduce blood pressure and avert a panic attack in people under stress.Glossary:nostalgic: causing a desire for things, persons, or situations of the past; causing homesicknessretention: the act of retaining; keeping, holding, or maintaining Why does the author use the term hard-wired in describing the sense of smell and the brain ?()

A. To describe the texture and feel of the olfactory nerve
B. To emphasize the close connection between smell and the brain
C. To compare the power of smell with that of other senses
D. To explain how the sense of smell evolved in early humans

Set 4THE TRICKSTER FIGURE IN MYTHOLOGY1.In the study of mythology, the character known as the trickster is a god, spirit, human, or animal who breaks the rules of the gods or nature, sometimes maliciously but usually with results that are positive. The rule breaking often takes the form of mischief or thievery. The trickster is usually male but occasionally disguises himself in female form. He can be cunning or foolish, or both, and often very humorous. His curiosity leads him into trouble, but he rescues himself with his sly wit. When he plays tricks, he performs important cultural tasks that benefit humans, and for this reason the trickster is a significant figure in world mythology.2.In different cultures, the trickster and the hero are combined in various ways. In Greek mythology, Prometheus steals fire from the gods and gives it to humans, a feat making him more of a hero than a trickster, and he is usually portrayed as an intellectual. In many Native American stories, Coyote also steals fire from the gods, but Coyote is usually more of a jokester or a prankster than an intellectual.3.The trickster is both creator and destroyer, giver and taker, one who tricks others and is tricked in return. The pranks of the trickster are compulsive and uncontrollable. He does not act consciously; he acts out of passion and impulse. He knows neither good nor evil, yet he is responsible for both. He possesses no morals, yet through his behavior morality comes into being. According to psychologist Carl Jung, the trickster is "a primitive cosmic being of divine-animal nature, on the one hand superior to man because of his superhuman qualities, and on the other hand inferior to him because of his unreason and unconsciousness."4.In Native American mythology, the majority of trickster myths concern the creation or transformation of the earth. Such stories have a trickster who is always wandering, who is always hungry, who is not guided by normal ideas of good and evil, and who possesses some magical powers. In some stories he is a deity, and in others he is an animal or human subject to death. Several of these myths feature Raven or Coyote as the trickster-hero.5.In many creation myths of the Pacific Northwest, Raven illustrates the transformational nature of tricksters. Raven is the greatest shapeshifter of all and can change into anything to get what he wants. In one story, there is darkness at the beginning of the world, so Raven decides he will find light. He flies far from the earth, searching in the darkness, until he spots a glimmer of light coming from a window in the house of the gods. Raven knows the gods are protective of their possessions, so he devises a trick. He perches on a pine branch next to the house and watches each day as the chief god’s daughter draws water from a nearby lake. He magically transforms himself into a pinyon seed and falls into the girl’s drinking cup. The girl swallows the seed, which grows within her body, and she eventually gives birth to a boy. The child delights his grandparents, and his laughter tricks the elder gods into revealing where they hide a shining ball of light. The gods give the child the ball to play with, and then Raven transforms back to a bird and flies off carrying the ball of light in his beak. He hangs the ball-the sun-in the sky, bringing light to the world.6.Coyote’s character is similar to that of Raven’s, and both appear in stories carrying out similar roles. In several stories from the American Southwest, Coyote steals fire from a group of "fire beings" and gives it to humans. In some tales Coyote wants to make human life more interesting, so he introduces sickness, sorrow, and death. He often teaches through negative example by employing the human vices of lying, cheating, and stealing. His tricks often bring about destructive natural phenomena, such as a great flood that destroys the earth. However, by causing the flood, Coyote leads the human race to a new and better world. Coyote shows us that at the heart of the trickster is a savior whose great gift to humans is showing them new ways of knowing and doing.Glossary:mischief: tendency to play tricks or cause minor troublemischief: the act of theft; stealingpinyon seed: the seed of a pine tree; pine nut The word maliciously in paragraph 1 is closest in meaning to ().

A. destructively
B. falsely
C. bravely
D. mistakenly

Set 3THE SENSE OF SMELL1.Smell is the most direct of all the senses. It is thought to be the oldest sense in terms of human evolution, which may explain why smell is hard-wired into the brain. The olfactory nerve, which manages the perception of smells, is essentially an extension of the brain. The olfactory nerve provides a direct link from receptors at the top of the nose to the portion of the brain that controls memory, emotion, and behavior.2.The olfactory system detects certain airborne chemicals that enter the nose and then transmits this chemical information to the limbic system in the brain. The olfactory region at the upper end of each nostril is yellow, moist, and full of fatty substances. The shade of yellow indicates the strength of the sense of smell: the deeper the shade, the keener and more acute it is. Animals have a very strong sense of smell, so their olfactory regions are dark yellow to reddish brown, while those of humans are light yellow.3.When an odorous substance enters the nose, it binds to olfactory receptor cells, the neurons lining the yellow upper portion of the nasal cavity. Olfactory receptor cells contain microscopic hairs called cilia that extend into the layer of mucus coating the inside of the nose. Odor molecules diffuse into this region and are absorbed by the cilia of the olfactory receptor cells. What this means is that when we hold a rose to our nose and inhale, odor molecules float up into the nasal cavity, where they are absorbed by five million olfactory receptor cells. The receptor cells alert the olfactory nerve, which sends impulses to the brain’s olfactory bulb, or smell center. Thus, olfactory information about the rose enters the brain’s limbic system, where, in most of us, it stimulates a feeling of pleasure.4.The limbic system of the brain integrates memory, emotion, and behavior. The system is composed of a group of related nervous system structures that are the functional center of emotions such as anger, fear, pleasure, and sadness. The components of the limbic system are linked to the cerebral cortex, the part of the brain involved in complex learning, reasoning, and personality. The cerebral cortex makes decisions about the emotional content of these unique human qualities after "consulting" the limbic system and other brain centers in processing and retrieving memories. It may, in turn, use memories to modify behavior.5.Scent may be the strongest trigger of memory and emotions. When we inhale a scent, receptors in the brain’s limbic center compare the odor entering our nose to odors stored in our memory. Along the way, memories associated with those odors are stimulated. A smell can be overwhelmingly nostalgic because it triggers powerful images and emotions. The waxy fragrance of crayons can instantly transport us to our second-grade classroom, or the scent of freshly mown grass can flood us with the joy of summer freedom. What we see and hear may fade quickly in short-term memory, but what we smell is sent directly to long-term memory.6.Smells can increase alertness and stimulate learning and retention. In one study, children memorized a word list, which was presented both with and without accompanying scents. The children recalled words on the list more easily and with higher accuracy when the list was given with scents than without, showing the link between smell and the ability to retain information. In another study, researchers examined how various smells can increase alertness and decrease stress. They found that the scent of lavender could wake up the metabolism and make people more alert. They also found that the smell of spiced apples could reduce blood pressure and avert a panic attack in people under stress.Glossary:nostalgic: causing a desire for things, persons, or situations of the past; causing homesicknessretention: the act of retaining; keeping, holding, or maintaining What happens when the cilia of the olfactory receptor cells absorb odor molecules ?()

A. The tiny hairs inside the nose become darker in color.
B. The nervous system activates the digestive system.
C. The olfactory nerve sends impulses to the brain.
D. Some receptor cells die and are replaced by new cells.

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