In recent decades, space–based observations have led astronomers to change their previous view that Pluto was the ninth planet in the solar system. By a strong majority, the International Astronomical Union voted to change the definition of what it means to be a planet. The new definition states that, in order to be called a planet, an object must meet three criteria. First, it must orbit the sun. Second, it must be large enough to have a round shape due to the force of its own gravity. Third, it must dominate the neighborhood of its orbit by clearing the region of other large bodies.

Pluto meets the first two criteria. It orbits the sun, is round in shape, and has an
estimated diameter of 2,400 kilometers. However, Pluto does not meet the third criterion because it does not dominate the region of its orbit. As a planet forms, it becomes the strongest gravitational body in its orbit, and this gravity causes it to sweep up asteroids, comets, and other debris around it. Pluto’s orbit remains crowded with other objects, many of which are nearly as large as Pluto itself. The new definition of planet is clear and precise, and Pluto does not qualify.

Astronomers now agree that Pluto is not a true planet. Instead, Pluto and its moons are part of a collection of objects called the Kuiper Belt. Astronomers have redefined Pluto as a dwarf planet, an object too small to be a real planet but too large to be a space rock. Unless Pluto gains mass by crashing into and absorbing the other objects in its orbit, it will remain a dwarf planet and not a true planet.

Key points:

•The lecture states that the decision to change Pluto’s status was controversial; scientists disagree about the decision. This contradicts the point in the reading that the decision was reached by a strong majority vote.
•The lecture states that critics think the new definition of planet is not adequate or realistic. This contradicts the point in the reading that the new definition is clear and precise.
•The lecture states that calling Pluto a dwarf planet causes controversy and confusion. This contradicts the point in the reading that astronomers agree that Pluto is a dwarf planet and not a true planet.

Research has taught us a lot about job satisfaction and the motivation of workers. First, workers are more motivated if their job offers a sense of community. A sense of community grows when workers get recognition for their accomplishments and when they believe their skills are being well used. Social organization in the workplace is important. Supervisors and co–workers have a tremendous influence on job satisfaction. When workers are asked what they like or do not like about their job, around 80 percent will mention the people they work with.

Second, while workers value traditional economic incentives such as pay and promotions, they also have needs and expectations that go beyond economic concerns. Workers need a sense of security in the workplace. Security comes from confidence in the system that they are part of, the quality of the product or service they provide, and the reputation of the company. Security comes from the personal satisfaction of knowing that their skills are being utilized in a way that contributes to the company’s success.

Third, the most satisfying jobs are those with a high level of autonomy, in which employees can make their own decisions about the pacing and sequence of work with minimal supervision. Job autonomy is most often found in high–pay and high–prestige occupations. In jobs in the middle or lower levels of pay and prestige, workers generally have less autonomy. The lower the occupational status, the more heavily supervised the workers are, and the fewer decisions they can make on their own.

Summarize the points made in the lecture, being sure to explain how they support specific points made in the reading passage.

Key points:

•The lecture states that the small work group fills important social and emotional needs of workers. This supports the point in the reading that workers are more motivated if their job offers a sense of community.
•The lecture states that the work group improves worker motivation because it promotes an atmosphere of security. This supports the point in the reading that workers need a sense of security in the workplace.
•The lecture states that the small work group gives individuals a sense of autonomy; workers need to feel in control of what happens during the workday. This supports the point in the reading that the most satisfying jobs are those with a high level of autonomy.

The term “alternative medicine” describes healing practices that are used in place of conventional “Western” medicine. Alternative medicine often rejects science–based medicine and includes therapies that developed out of religious and cultural traditions. Examples are naturopathy, herbalism, meditation, biofeedback, hypnosis, homeopathy, and nutritional–based therapies. Advocates of alternative medicine believe that the various alternative methods are more effective than conventional medicine in treating a wide range of medical conditions.

Dissatisfaction with conventional medicine leads many people to seek alternative therapies. Some people choose alternative medicine because they do not trust traditional authority figures, such as the physician, or they dislike the current delivery methods of scientific medicine, particularly the over–reliance on synthetic drugs. Some patients prefer alternative therapies because they are averse to the painful or dangerous side effects of biomedical treatments. The majority of alternative medicine users find health–care alternatives to be more in agreement with their own values, beliefs, and philosophy about health. Many have a holistic orientation to health, a belief that the body, mind, and spirit are connected.

To meet the growing demand for alternative treatments, a variety of schools and colleges offer courses in alternative medicine. Even conventional medical colleges have started offering courses. Most alternative medicine programs take a holistic approach to health that explores the interconnection between the mind and body. Mind–body medicine works under the premise that the mind can affect bodily functions and symptoms. Other alternative medicine programs emphasize the study of substances found in nature such as herbs, foods, vitamins, and minerals.

Summarize the points made in the lecture, being sure to explain how they challenge specific points made in the reading passage.

Key points:

•The lecture states that health–care practices should be based solely on scientific evidence. This challenges the point in the reading that alternative medicine often rejects science–based medicine.
•The lecture states that people turn to alternative therapies because they are misinformed or misled. This challenges the point in the reading that people seek alternative therapies because they are dissatisfied with conventional medicine.
•The lecture states that alternative medicine does not require practitioners to have any formal training or professional credentials. This challenges the point in the reading that a variety of schools and colleges offer courses in alternative medicine.

Now listen to part of a lecture on the topic you just read about.

Okay, you’ve all read about how Pluto is no longer a planet. Well, let me offer another view. First of all, you should know that the decision by the International Astronomical Union was not unanimous. In fact, the vote was controversial, and there is a lot of scientific disagreement about the decision to change Pluto’s status. Several scientists maintain that Pluto is indeed a planet. Pluto orbits the sun, has enough gravity to pull itself into a ball, and has its own satellites—moons. While its orbit isn’t completely clear of debris, Pluto is still the biggest body in its neighborhood.

Second, about the new definition of planet, well, critics don’t find it to be adequate or realistic. They believe that, instead of narrowing the definition, it should have been widened to include Pluto and similar bodies. Our solar system is complex. It contains countless objects of all sizes. The definition of planet should include any large body that revolves around the sun and is not itself a satellite of another planet. This broader definition would make full–fledged planets of 50 or more additional objects in the solar system.

Finally, calling Pluto a “dwarf planet” causes controversy and confusion. Why is a dwarf planet not a real planet? The astronomer’s union did not consider the historical and cultural role that Pluto has played. For 80 years, children have learned about the nine planets in our solar system. Saying that Pluto is not a real planet confuses both teachers and students. It has forced us to go back and rewrite textbooks, redraw charts, and rebuild museum exhibits.

Summarize the points made in the lecture, being sure to explain how they contradict specific points made in the reading passage.

Now listen to part of a lecture on the topic you just read about.

Companies organized around the concept of the small work group generally have high levels of worker satisfaction. There are several reasons for the success of the small work group.

First, the group fills important social and emotional needs of workers. By small work group, I mean a group of usually around three to fifteen people with one lead person. The work group is the basic unit of a company’s social organization. What takes place day to day within that group affects worker attitudes, motivation, and productivity—and ultimately, the quality of the company’s product or service.

Second, the work group improves worker motivation because it promotes an atmosphere of security. When workers are members of a team, they know their performance matters to the success of the group. Knowing that their skills contribute to the team gives workers a sense of ownership and accomplishment. Ultimately, when workers have a sense of team pride and personal fulfillment, they are more valuable to the organization.

Third, the small work group gives individuals a sense of autonomy. Workers need to feel in control of what happens during the workday. They feel alienated when they have no voice. If workers have their say—especially within the work group—they feel a greater sense of pride in their work. Managers have to accept that workers deserve to have a voice in the decisions that affect them. Workers should be able to participate in the setting of goals and the evaluation of results. Managers have to face this reality if they want to have a highly motivated workforce.

Summarize the points made in the lecture, being sure to explain how they support specific points made in the reading passage.

Now listen to part of a lecture on the topic you just read about.

Now I’d like to offer a different view of alternative medicine. First, health–care practices should be based solely on scientific evidence. Conventional medicine is based on science. It applies health science, biomedical research, and medical technology to diagnose and treat injury and disease. Alternative medicine, on the other hand, is not based on science. This means that alternative practices can not be tested, refuse to be tested, or consistently fail tests. Because alternative therapies are not based on scientific evidence, they can not be proven effective.

Second, people turn to alternative therapies because they are misinformed or misled. There are 40 million websites advertising alternative therapies, and most of them are unproven. Many people believe in these treatments because they want something to believe in. There’s also been an increase in conspiracy theories towards conventional medicine, such as the belief that medicine makes patients dependent on drugs. These beliefs reflect the low level of scientific literacy among the public and an increase in anti–scientific attitudes.

Most importantly, with alternative medicine, there’s no guarantee that a practitioner has any formal training or professional credentials. Conventional medicine, on the other hand, requires a degree from a university medical school, followed by a period of supervised practice or internship, residency, postgraduate training, and in most countries, a legal requirement for doctors to be licensed or registered by a national medical organization. With alternative medicine, anyone can set up a practice as a “healer,” with no oversight, no peer review, and no scientific evidence that the treatments are safe or effective.

Summarize the points made in the lecture, being sure to explain how they challenge specific points made in the reading passage.