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Urbanization and City Infrastructure Urbanization is defined as the increase in a city’s population over time and can occur due to a variety of factors including the natural expansion of a city’s population, the conversion of a rural area to an urban one, or the migration to urban areas by those who previously inhabited rural environments. ■(A) Urbanization is an ever-increasing trend; one that can be observed in areas throughout the world as economies begin to rely more on manufacturing and business for revenue. ■(B) Working and living in large cities is gradually replacing the traditional rural careers such as small-scale agriculture. ■(C) It is estimated that within the next century, more than half of the world’s citizens will reside in cities. ■(D) While some cities are planned, most cities are organic, meaning that urbanization in these areas takes place with little or no advanced planning. While the increase in urban areas and its population has yielded positive effects such as an increased concentration of businesses and more career opportunities, researchers have also discovered a host of detrimental effects on the areas in transformation from rural areas to urban centers. The concerns about urbanized areas worldwide differ somewhat in their relative importance, but many cite traffic congestion, inadequate public transportation, insufficient waste disposal facilities, inadequate solid waste collection, and a lack of water and sewage treatment facilities as primary concerns. One hundred years ago in Australia, the commute from Paramatta to the center of Sydney took approximately an hour by horse and cart. Today, the same trip in a car takes longer. Opponents of unplanned urbanization have also pointed out the destruction of agricultural land and animal habitat as a negative consequence of urbanization. Many of these problems could be eliminated, or at least mitigated, through the construction and maintenance of appropriate city infrastructure. Although the term is somewhat ambiguous, it was traditionally understood to mean roads and sewers. However, the U.S. National Research Council opted to widen the definition of public works infrastructure to refer to roads, bridges, mass transit systems, and water and waste management systems. Chief among the concerns of city dwellers is the issue of traffic jams and general congestion, and the corresponding difficulty in navigating the streets of any large urban area. Appropriate infrastructure, however, could serve as a useful tool in curtailing this problem. Two factors that exacerbate traffic congestion in a typical city are narrow streets and a lack of off-road parking, which would force many workers to park on the side of the road. Several solutions to the excessive traffic in urban areas have been proposed. Firstly, the construction of bypasses would eliminate the amount of traffic in the downtown areas, as travelers could use faster, more direct routes to arrive at their destination. Parking concerns could be addressed by constructing parking garages consisting of several stories. In this way, many cars could be stored in a relatively small amount of space. Closely related to the previous problem is the issue of inadequate public transportation. People will choose to ride buses; however, the system must be efficient and reliable. The establishment of a variety of mass transit systems such as subways, buses, and ferries could provide a feasible alternative to those that use their own vehicles to travel to their jobs in the city. Many cities have concerns about the problems involving waste collection and disposal. Along with education about waste diversion techniques such as composting and recycling, the development of city infrastructure can play a key role in ensuring adequate waste treatment. This would include the construction of easily accessible recycling facilities and appropriately placed composting facilities. In addition, urban areas should ensure there is a citywide transit system in place to collect solid waste. Finally, citizens in many urban areas have concerns regarding sewage treatment plants and water treatment facilities. The development of such facilities in an acceptable area, typically in a location outside of the city, could effectively deal with these concerns. Not only would this infrastructure improve the health of the citizens, but it would also benefit the environment by reducing the amount of pollution in the form of sewage entering water sources. According to paragraph 3, what is one negative effect of urbanization
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Urbanization and City Infrastructure Urbanization is defined as the increase in a city’s population over time and can occur due to a variety of factors including the natural expansion of a city’s population, the conversion of a rural area to an urban one, or the migration to urban areas by those who previously inhabited rural environments. ■(A) Urbanization is an ever-increasing trend; one that can be observed in areas throughout the world as economies begin to rely more on manufacturing and business for revenue. ■(B) Working and living in large cities is gradually replacing the traditional rural careers such as small-scale agriculture. ■(C) It is estimated that within the next century, more than half of the world’s citizens will reside in cities. ■(D) While some cities are planned, most cities are organic, meaning that urbanization in these areas takes place with little or no advanced planning. While the increase in urban areas and its population has yielded positive effects such as an increased concentration of businesses and more career opportunities, researchers have also discovered a host of detrimental effects on the areas in transformation from rural areas to urban centers. The concerns about urbanized areas worldwide differ somewhat in their relative importance, but many cite traffic congestion, inadequate public transportation, insufficient waste disposal facilities, inadequate solid waste collection, and a lack of water and sewage treatment facilities as primary concerns. One hundred years ago in Australia, the commute from Paramatta to the center of Sydney took approximately an hour by horse and cart. Today, the same trip in a car takes longer. Opponents of unplanned urbanization have also pointed out the destruction of agricultural land and animal habitat as a negative consequence of urbanization. Many of these problems could be eliminated, or at least mitigated, through the construction and maintenance of appropriate city infrastructure. Although the term is somewhat ambiguous, it was traditionally understood to mean roads and sewers. However, the U.S. National Research Council opted to widen the definition of public works infrastructure to refer to roads, bridges, mass transit systems, and water and waste management systems. Chief among the concerns of city dwellers is the issue of traffic jams and general congestion, and the corresponding difficulty in navigating the streets of any large urban area. Appropriate infrastructure, however, could serve as a useful tool in curtailing this problem. Two factors that exacerbate traffic congestion in a typical city are narrow streets and a lack of off-road parking, which would force many workers to park on the side of the road. Several solutions to the excessive traffic in urban areas have been proposed. Firstly, the construction of bypasses would eliminate the amount of traffic in the downtown areas, as travelers could use faster, more direct routes to arrive at their destination. Parking concerns could be addressed by constructing parking garages consisting of several stories. In this way, many cars could be stored in a relatively small amount of space. Closely related to the previous problem is the issue of inadequate public transportation. People will choose to ride buses; however, the system must be efficient and reliable. The establishment of a variety of mass transit systems such as subways, buses, and ferries could provide a feasible alternative to those that use their own vehicles to travel to their jobs in the city. Many cities have concerns about the problems involving waste collection and disposal. Along with education about waste diversion techniques such as composting and recycling, the development of city infrastructure can play a key role in ensuring adequate waste treatment. This would include the construction of easily accessible recycling facilities and appropriately placed composting facilities. In addition, urban areas should ensure there is a citywide transit system in place to collect solid waste. Finally, citizens in many urban areas have concerns regarding sewage treatment plants and water treatment facilities. The development of such facilities in an acceptable area, typically in a location outside of the city, could effectively deal with these concerns. Not only would this infrastructure improve the health of the citizens, but it would also benefit the environment by reducing the amount of pollution in the form of sewage entering water sources. The word "mitigated" in the passage is closest in meaning to
What will likely happen before the student goes to the library tomorrow
What is the lecture mainly about
Natural Selection First coined by Darwin, the term natural selection refers to the process at the core of evolutionary theory. Simply put, Darwin believed that every living organism had to struggle to survive and reproduce. By random chance, some individuals in a species would have characteristics that made them better adapted to this struggle than their contemporaries. Such individuals would be more likely to reproduce and pass their characteristics on to their offspring. Over many generations, a series of small differences in characteristics would accumulate, until eventually the creatures that were produced would be so different from their original ancestors that they would constitute a new species. ■(A) Although Darwin did not know how variations between individual members of the same species were able to arise in the first place or how such traits could then be passed on from species to species, we now know that this process occurs through genes. ■(B) Genes determine what characteristics an organism will possess, from its size to its skin color to its gender. ■(C) Sometimes these genes become damaged or altered--a process known as mutation. ■(D) Most mutations are either too small to have any effect, or have detrimental effects on the organism. A few, however, can be beneficial to helping an organism survive. The organisms with these beneficial mutations are the ones that .survive and reproduce, passing their particular genetic mutation on to future generations. Originally, Darwin thought that two particular types of traits were naturally selected for evolution. The first type included any and all traits that helped an organism survive, either by giving it easier access to food, better protection from predators, or superior adaptability to shifting environmental conditions. Several examples of the natural selection of such traits have been observed since Darwin first proposed his theory. The most often cited example is the coloration of moths near industrial centers. Some of them have white wings and the others have black wings. Under normal conditions, the lighter-colored moths predominate since white moths are less visible against the light-colored bark of the trees in the forests where they live, which means they can more easily avoid predators. Near industrial centers, however, darker-colored moths predominate, as the pollution from the factory has darkened the bark of the nearby trees. Moths landing on these trees are much more difficult to see if they have black wings. This trait has now become most common in moth populations living in areas where pollutants have changed the color of the tree bark. The second type of naturally selected traits envisioned by Darwin involved those characteristics of an organism that made it easier for that organism to find a mate. This form of natural selection, often called sexual selection, was thought to explain the existence of highly developed traits in certain animals that seemed to play no particular role in their survival, and that in some cases seemed to make it even harder for them to survive. A prime example of such a trait is the peacock’s elaborate, colorful tail feathers. A long, unwieldy tail that can expand into a display of bright colors that draws the attention of any predator in the vicinity seems less likely than that of other kinds of birds to help the bird survive. However, researchers discovered that peahens invariably chose to mate with those peacocks whose tail feathers produced the most artistic displays. Thus, although the peacock’s tail feathers have no adaptive function in terms of coping with survival pressure, the gene that controls feather color is the one that is most likely to be passed on because of its role in the mating process. Many scientists now believe that a third type of naturally selected characteristics exists, namely those that may be harmful to an individual organism but beneficial to that organism’s species. This helps to explain the persistence of certain traits that were viewed under traditional evolutionary theory as not assisting in adaptation. For instance, in many animal species, including humans, a small subset of the population is homosexual. Under the old view of evolution, this could not be accounted for since homosexual individuals do not normally reproduce, meaning the gene that codes for it should have long been phased out of the gene pool. However, recent studies among wild sheep populations have found that the prevalence of homosexuality in the sheep population increases in times of severe food shortages, causing the sheep to form stronger bonds with sheep of the same sex than they otherwise would. As a result, instead of fighting over a particular food source, these sheep share the food they find with each other, increasing the species’ chance of surviving hard times. Though still controversial, the idea that traits may be naturally selected because of their benefits to the species instead of their benefits to the individual is rapidly gaining acceptance in the scientific community because of the wide array of characteristics that it can explain, including the human tendency towards altruism, Directions: An introductory sentence to a brief summary of the passage is given below. Complete the summary by adding the THREE answer choices that express the most important ideas in the passage. Some answer choices do not belong in the summary because they express ideas that are not given in the passage or are minor ideas in the passage. This question is worth 2 points. Natural selection is the name given by Darwin to the process whereby new species evolve over time as individuals with useful traits survive and reproduce, passing those traits on to new generations. ·__________________________________________ ·__________________________________________ ·__________________________________________ Answer Choices 1. Darwin believed that natural selection favored organisms that had traits that could help them find food and survive predator attacks and environmental pressures. 2. Darwin explained advanced traits that did not seem to affect an organism’s survival as being characteristics useful in finding a mate. 3. Moths near industrial centers evolve dark coloration when the trees in which they live are blackened by pollution from nearby factories. 4. Recently, scientists have expanded the idea of natural selection to include traits that benefit the species as a group, even when those traits seem harmful to the particular individuals who possess them. 5. The peacock’s colorful tail feathers are meant to attract peahens, which view the bright colors involved in the display as a sign of the male’s good health. 6. Religious groups’ opposition to evolutionism has led some schools to reconsider teaching it, even though it is an established scientific theory with much evidence to prove it.
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