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Contemporary's GED Science
Robert Mitchell

Science in Personal and Social Perspectives

GED Practice Quiz


Choose the one best answer to each question. When you have finished the quiz, click on Submit Answers to receive feedback and results. You may also choose to e-mail your results to your instructor.

Questions 1 through 3 refer to the following information.

Until recently, aging has been associated with declining body functions. Decreased heart, kidney, and brain functions were considered a natural part of the aging process. In the last decade, scientists have begun to suspect that this decline is not an unavoidable part of growing old. As more people live longer, one fact has become clear: Different people age at different rates.

Why do some people not age as fast as others? A few years ago, the best answer would have been a combination of good luck, good habits, and good genes. But these answers were not entirely accurate. After all, some athletes die young, while some heavy smokers live to old age.

The real answer is probably much more complicated. Biological, psychological, and environmental factors all influence what happens to a person as he or she grows older. New studies are concentrating on chemical pathways by which emotions and attitudes affect the body. Feelings such as loneliness and a loss of control over one’s own life may play a very real part in the decline associated with age.

This new emphasis in no way denies that physical changes occur as one ages. By fifty years of age, some lung capacity is lost, and blood vessels are narrower. However, significant declines do not occur in the absence of disease or damage.


Which of the following statements best summarizes the passage?
Need a Hint?
A)Scientists are learning that little can be done to halt the process of aging.
B)Aging is probably due to emotional, biological, and environmental factors that influence people differently.
C)Much of the biological decline of aging is probably due to a lifetime of unhealthful habits.
D)Physical decline is probably not very important in aging.
E)Mental decline occurs faster than physical decline in the aging process.

Which of the following statements represents an opinion rather than a fact about aging?
Need a Hint?
A)Lungs do not function quite as well after the age of fifty.
B)More people are living longer these days.
C)Decline in body functions is usually the result of disease or damage, not aging.
D)Genetics, physical fitness, and emotional factors all contribute to aging.
E)A 75-year-old person is too old to hold a position of responsibility.

Many researchers believe that stress can trigger changes in the body. Below are five statements about how people respond to stress.

I.Stress can trigger the release of hormones that affect blood pressure and heart rate.
II.People who have friends and family to support them recover more quickly from stressful situations.
III.In times of stress, the brain may release mood-altering chemicals.
IV.When people experience stress, the number of disease-fighting white blood cells in their blood decreases.
V.People who are allowed to make their own decisions appear more youthful.

Which of these statements support the conclusion that stress and emotions can affect bodily functions in specific ways?
Need a Hint?
A)I only
B)V only
C)I and II only
D)II and III only
E)I, III, and IV only

Questions 4 and 5 refer to the following information and diagram.

Ultraviolet light (UVL) in solar radiation can kill living organisms. However, not much UVL reaches Earth’s surface because the gases oxygen and ozone in the upper atmosphere absorb it. Oxygen absorbs a little UVL and in the process changes to ozone. The ozone then absorbs large amounts of UVL.

There is evidence that the ozone in the atmosphere is disappearing, and some scientists believe that pollution may be stopping the reaction that converts oxygen into ozone. This would mean less ozone would be available to stop the UVL from reaching Earth. Overexposure to UVL can lead to skin cancer, cataracts, and weakened immune systems in humans. Increased UVL can also lead to reduced crop yield and disruptions in the marine food chain.

Some scientists suggest that the chemical chlorofluorocarbon (CFC)—used in air conditioners, refrigerators, spray cans, and cleaning solutions—may be the main pollutant.

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What might be the effects of ozone disappearing from the upper atmosphere?
Need a Hint?
A)There will be less ultraviolet light in the atmosphere.
B)The atmosphere will absorb more ultraviolet light.
C)Overexposure to UVL can lead to skin cancer, cataracts, and weakened immune systems as well as reduced crop yield and disruptions in the marine food chain.
D)Pollutants in the atmosphere will increase.
E)Less oxygen will form in the atmosphere.

Which of the following is a conclusion that CANNOT be drawn from the passage?
Need a Hint?
A)Ultraviolet light can kill living organisms.
B)Ozone absorbs ultraviolet light.
C)Ozone is a form of oxygen.
D)Chemicals, such as CFCs, used on Earth are decreasing the ozone.
E)There is evidence that the ozone in the atmosphere is disappearing.

"Ultrasound" is the name given to sounds so high that the human ear cannot detect them. Ultrasound can be used in medicine to detect certain ailments and can also be used to check the development of an unborn child. Ultrasound waves sent into the mother’s womb bounce back and create an outline of the baby’s image on a screen.

Which of the following would NOT be revealed by an ultrasound image?
Need a Hint?
A)the baby’s motions
B)the presence of twins
C)the baby’s weight
D)approximate body size
E)approximate head size

Questions 7 and 8 refer to the following information.

Mining companies often scrape away layers of soil to obtain minerals lying below the earth’s surface. Some companies store the removed soil in a pile. This means that surface soil ends up at the bottom of the pile. When the mineral excavation is completed, the miners return the soil to its original spot.

Such mining practices have created problems. Biologists know that certain organisms live at very specific depths in the soil. Many of these organisms recycle nutrients and produce fertilizers for plants. Turning the soil upside down during excavation destroys the environments of these soil organisms, so they soon die. Although companies carefully replace the stored soil in the hole, the organisms have already been killed. Nutrients are no longer recycled, and the land becomes barren.


What assumption is made when mining companies replace the excavated soil?
Need a Hint?
A)That replacement of the soil will restore the land to its original fertile condition.
B)That microorganisms are extremely sensitive to their environmental conditions.
C)That microorganisms are an essential part of land productivity.
D)That soil fertility is dependent on the nutrients and fertilizers present.
E)That turning the soil upside down may interfere with the ability of organisms to survive.

A person who objects to mining methods that excavate soil would probably place a high value on what?
Need a Hint?
A)the latest technology in mining
B)conservation of soil resources
C)underground metals and minerals
D)the use of artificial fertilizers
E)keeping fuel costs low

Questions 9 and 10 refer to the following information.

Nuclear power plants currently provide about 10 percent of the electricity used in the United Sates. As the need for power continues to grow, so do problems connected with nuclear power plants. A growing stock of nuclear wastes is one of the major problems.

At present, nuclear power companies are sealing and storing wastes directly on their power plant sites. But they agree that this is just a temporary solution. In the 1970s, plans got underway to reprocess nuclear assemblies so their parts could be used to make more power. Then in 1977 the U.S. government banned the building of reprocessing plants. Political leaders feared that during the shipping and recycling of the nuclear wastes, someone might steal enough radioactive materials to manufacture an atomic bomb. In 1981 the government lifted the ban on reprocessing. Still no companies have built reprocessing plants because they are so expensive.


What was the value behind public officials’ decision to ban nuclear reprocessing centers?
Need a Hint?
A)concern for national security
B)interest in saving money
C)concerns for public health
D)determination to investigate radioactivity
E)desire for speed and efficiency

Which of the following actions would be based on a value for operating nuclear power plants safely?
Need a Hint?
A)Electric companies switch from hydroelectric power plants to nuclear plants.
B)Protesters picket an electric power company’s offices after a rate increase.
C)Construction workers at a new power site go out on strike for more benefits.
D)Power companies band together to finance research for new waste storage methods.
E)Power companies using nuclear plants charge lower rates than companies that burn coal.