The widespread use of antibiotics has created a frightening threat to our safety. While antibiotics have offered life-saving treatment for countless diseases, their misuse and overuse have contributed to the evolution of deadly bacteria that are resistant to treatment. Although there is a reluctance to give up the demand for antibiotics, most people accept scientists’ warnings of impending catastrophe.
Which choice best explains why doctors now prescribe antibiotics less often than in the past?
- A . The newer antibiotics are too expensive for the average consumer.
- B . Insurance does not cover many antibiotic prescriptions.
- C . Antibiotic use causes frequent digestive upsets.
- D . Time constraints prevent doctors from writing as many prescriptions.
- E . Bacteria become resistant to treatment by certain antibiotics.
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The pH scale is a measure of the acidity of a substance. The numerical range of the scale is from 0.0 to 14.0. A midpoint pH of 7.0 designates a neutral substance (neither acid nor base). A pH lower than 7.0 denotes an acid substance, whereas a pH higher than 7.0 denotes a basic substance.
The pH scale is a measure of the acidity of a substance. The numerical range of the scale is from 0.0 to 14.0. A midpoint pH of 7.0 designates a neutral substance (neither acid nor base). A pH lower than 7.0 denotes an acid substance, whereas a pH higher than 7.0 denotes a basic substance.
Which of the following substances is the MOST acidic?
- A . lemon juice(pH = 2.3)
- B . vinegar(pH = 2.8)
- C . orange juice(pH = 3.5)
- D . milk(pH = 6.5)
- E . seawater(pH = 8.4)
As pressure in a closed container is increased, the volume, or amount of space that a gas takes up, decreases. Divers who work underwater use tanks containing oxygen in order to breathe. The amount of oxygen in the tanks allows the divers to stay underwater for some time, yet the tanks are not huge.
Which statement best explains this occurrence?
- A . Oxygen has to be in small metal tanks so that divers don’t sink.
- B . Oxygen takes up only a small amount of the air that we breathe.
- C . If the tanks are small, the fish will not be frightened by the divers.
- D . Since the oxygen is under pressure, a large amount of oxygen can be placed in these small tanks.
- E . Most divers don’t stay underwater for a very long time because they get very cold quickly.
The microorganisms that cause food to spoil grow best at room temperature and in the presence of water.
Which of the following actions BEST helps prevent food spoilage?
- A . exposing the food to air
- B . keeping the food at room temperature
- C . adding water to the food
- D . freezing the food
- E . covering the food while warm
All kerosene stoves produce carbon monoxide and carbon dioxide gases as by-products of combustion. Both gases are dangerous to human beings.
When using a kerosene stove, which action provides the best protection against these harmful gases?
- A . keeping a fire extinguisher near the stove
- B . locating the stove far from walls and furniture
- C . using only the correct grade of kerosene
- D . circulating air around the room with a fan
- E . keeping the room well ventilated
Atoms in gases are in constant motion and in constant collision with each other. When atoms of A and B collide, they react to form a product P.
What is the effect of increasing pressure on the gases?
- A . an increase in P
- B . a decrease in P
- C . an increase in A
- D . an increase in B
- E . no change in A, B, or P
The most realistic description of energy flow through an ecosystem is a food web that represents an interconnected series of food chains. In general, the greater the number of alternative channels through which energy can flow, the greater the stability of the food web and the ecosystem.
The diagram shows a typical food web for a wet meadow. The hawk and the fox obtain nourishment by preying upon rabbits, frogs, snakes, and mice. The fox may even eat grasshoppers. If, for example, the rabbit population is reduced, possibly because of bad weatherduring the breeding season, the fox and hawk would shift their predatory pressure to other forms of prey. The rabbit population would then have a chance to bounce back and the ecosystem would remain stable.
Rabbits are destroying a farmer’s vegetable garden.
Based on the food web, if the farmer removes the rabbits, which other organisms might be directly affected?
- A . foxes and snakes
- B . hawks and snakes
- C . grasshoppers and mice
- D . foxes and hawks
- E . grasshoppers and grass
A person is interested in trilobites. A book on which subject would most likely furnish information about trilobites?
- A . physics
- B . chemistry
- C . biology
- D . nutrition
- E . astronomy
Vertebrates, animals with backbones, are divided into the following five major groups: fish, reptiles, amphibians, birds, and mammals. Some characteristics of these groups are given
in the table below.
Which statement is true if an animal lives in water, does not lay eggs, and is warmblooded?
Exhibit:
- A . a fish
- B . a reptile
- C . a mammal
- D . an amphibian
- E . a bird
The greenhouse effect explains why a car’s interior can get hot on a sunny day even if it is cool outside. The glass windows allow the Sun’s rays to pass through to the interior but prevent heat rays from escaping to the outside. Certain gases, such as carbon dioxide and nitrous oxide, act like the glass in a greenhouse when they are present in the atmosphere.
Both natural and human activities lead to the release of gases that contribute to the greenhouse effect. During recent summers, forest fires have contributed to the loss of millions of acres of forest. These fires have resulted in the release of smoke and ash as well as greenhouse gases.
Based on the information, which statement most likely predicts the result of ongoing widespread forest fires?
- A . Forest fires are unlikely to affect atmospheric temperature.
- B . Forest fires decrease the amount of atmospheric greenhouse gases.
- C . Greenhouse gases could help form new animal species.
- D . There could be a gradual increase in average atmospheric temperatures.
- E . There could be a gradual decrease in average atmospheric temperatures.
Gases are one of three common states of matter and are affected by changes in temperature, volume, and pressure. When the pressure of a gas in a closed container becomes too high, it can cause the container to burst. The graph below illustrates the relationship between pressure and temperature (K) for ordinary gases.
Aerosol cans contain a pressurized gas that is used to propel, or spray, the contents out of the can. Many aerosol cans have labels that warn the users against incinerating (burning) them because of the danger of explosion.
What would happen to the pressure of the gas if the temperature inside the can increases?
- A . vary
- B . increase
- C . decrease
- D . remain the same
- E . increase, and then decrease
The pH of a liquid is a measure of its acidity or its alkalinity. Even small changes in pH of human blood can cause very serious health problems.
Carbon dioxide (CO2), is one of the dissolved gases present in healthy blood. CO2 normally mixes with the water in blood to form a mild acid, carbonic acid, which lowers the blood pH.If a health problem causes the dissolved carbon dioxide to increase or decrease, the blood’s pH would change and could produce an unhealthy pH level.
Based on this information, which statement best summarizes the blood condition that might result when an individual has a respiratory condition that causes the blood to contain too much CO2?
- A . The blood pH will remain the same.
- B . The blood pH will be lowered.
- C . The blood will be less acidic.
- D . The blood’s white cell count will be greatly decreased.
- E . The blood will clot more quickly.
— ExhibitC
When an object is being raised against gravity, work is being done. Gravity is the force that must be overcome to lift an object. The amount of work done is determined by how high the object is lifted and the mass of the object. The higher an object is lifted, the more work is done.
If each book in the diagrams has the same mass, which diagram shows the most work done?
- A . A
- B . B
- C . C
- D . D
- E . E
As plants grow, they absorb nutrients from the soil. Plant leaves can be carefully observed to determine the relative healthiness of the plant and whether it is suffering from a nutrient deficiency. The chart below shows the most common nutrient deficiencies and their effects on plant leaves.
Sometimes an observed symptom can have more than one cause.
Based on the information, which plant leaf symptom could have resulted from more than one type of nutrient deficiency?
- A . green leaves
- B . dark leaves
- C . yellow leaves
- D . small leaves
- E . distorted leaves
The results of a study of an experimental drug treatment seem to suggest that it is quite effective in treating an eye disease. The table below indicates the results of the use of the experimental drug therapy on 500 males who are 40C60 years old.
Based on the information and table, which statement is the best conclusion?
- A . Most of the human subjects in the study would have had a natural reversal of the symptoms even if they were not treated.
- B . The strong recovery rate of human subjects treated with established drug therapy makes the experimental drug therapy unnecessary.
- C . The experimental drug therapy shows promise, but it needs to be tested much more fully.
- D . The experimental drug therapy can now be used with any patient who has this disease.
- E . Similar results would have been obtained from a study of females in the same age group.
The sugars and starches in the human diet are broken down into glucose in the digestive system. This glucose passes from the small intestine into the blood. Human blood glucose levels are regulated by two hormones produced by the Islets of Langerhans in the human pancreas. The hormones are insulin, which lowers the level of blood glucose, and glucagon, which raises it.
Which statement best describes what happens after one eats a meal high in sugar and starches?
- A . The insulin level in the blood increases.
- B . No hormonal changes occur.
- C . The insulin level in the blood remains about the same.
- D . The insulin level in the blood decreases.
- E . The glucagon level in the blood increases.
Different enzymes in the human digestive system can digest food material only at specific levels of acidity (pH).
Based on the information, what can be concluded about enzymes in the digestive system?
- A . Enzymes become active in the large intestine.
- B . The digestive system contains few enzymes.
- C . Much of the food we eat cannot be digested.
- D . Food is digested only in the stomach.
- E . Different enzymes are active in different parts of the digestive system.
Our genes consist of DNA molecules. DNA fingerprinting allows the detection of DNA
fragment patterns in different people. In this process, enzymes are used to "cut" a person’s DNA into pieces. The length of these fragments differs from person to person and, therefore, there is little chance that two or more people will produce the same pattern. The DNA fragments of different people can be readily compared. DNA fingerprinting has many applications in law enforcement, medicine, and other areas.
The diagram below lists simulations of the DNA "fingerprint" band patterns for six individuals―a missing child and five young people who have the missing child’s physical characteristics.
Based on the DNA diagram, which of the five children might be related to the missing child?
- A . Child 1
- B . Child 2
- C . Child 3
- D . Child 4
- E . Child 5
Exhibit:
Based on the illustration, at which point on the ski slope above would the skier have the highest kinetic energy?
- A . 1
- B . 2
- C . 3
- D . 4
- E . 5
A scientist published his work in a scientific journal, and it generated much excitement in the scientific community. However, when other scientists across the world did the same experiment to try and repeat the results, it proved to be impossible.
When this type of event occurs, which statement describes the most important factor about a scientific finding’s acceptance by the scientific community?
- A . presented by a team of scientists
- B . reproducible by other scientists
- C . of considerable practical value
- D . published in a scientific journal
- E . based on an important concept
There is a difference between a chemical mixture and a chemical compound. The properties of a mixture can vary because the amount of each material in the mixture is not always the same. A compound, however, is always composed of a definite amount of particular elements.
Which substance is a compound?
- A . city air
- B . salad dressing
- C . water
- D . concrete
- E . toothpaste
The shape and structure of the teeth in the mouth of an animal determine their function in obtaining its food. The broad, sharp incisors are used for biting. The long, pointed canine teeth are used for tearing food, while the molars, which have a larger surface area, are used for grinding food.
Exhibit:
In certain animals, the canine teeth are longer than other teeth.
Which of the following animals would be likely to have longer canines?
- A . rabbit
- B . wolf
- C . cow
- D . horse
- E . deer
A clear container of hydrogen peroxide breaks down to form water and oxygen in approximately one month. When an enzyme known as catalase is added to hydrogen peroxide, water and oxygen are formed almost immediately.
Which of the following actions explains why this effect of catalase is typical of an enzyme?
- A . acts as a preservative
- B . reacts with protein
- C . forms water and chlorine gas
- D . is used up in the reaction
- E . changes the rate of the reaction
Science is a systemized body of knowledge based on observation and experimentation. Technology involves applied science and the practical applications of scientific knowledge. The making of lenses for eyeglasses is a technology that is based on the scientific principles of optics explaining how light rays are bent by finely ground lenses.
Which example would be considered science rather than technology?
- A . can opener
- B . structure of the atom
- C . seesaw
- D . microscope
- E . fishing rod
One wavelength is the distance from one crest of a wave to the next crest or from a trough (low point of a wave) to the next trough. The frequency of a wave is the number of crests that pass any given point each second.
Which of the following waves demonstrates the LOWEST frequency?
A)
B)
C)
D)
E)
- A . Option A
- B . Option B
- C . Option C
- D . Option D
Susan is studying air pressure and makes a simple mercury barometer as shown below. She knows that air exerts pressure. More pressure on the surface of the mercury in the bowl will cause the mercury level to rise. Less pressure will cause the mercury to fall. High barometric pressure is often associated with fair weather, and low barometric pressure is associated with rain.
Susan is enjoying a bright, sunny day when she hears a local weather forecaster predict rain for tomorrow.
When Susan checks her barometer tomorrow, which change is she most likely to note?
- A . totally fill the tube
- B . have risen by about 5%
- C . have risen by more than 10%
- D . have fallen
- E . remain unchanged
If a weight with a string attached is swung in a horizontal circular motion around in the air, the path of the weight will appear as shown in the figure at the left.
If the string breaks when the weight is at position A, the weight will fly away in a straight line tangent to the circular path.
In order for the weight to hit an object located at position X, the person should let go of the string when the weight is located at which position?
- A . B
- B . C
- C . D
- D . E
- E . F
An autotroph is an organism that can make its own food. A heterotroph, an organism that is unable to make its food, relies on other living things for food and energy.
Which organism listed below could be classified as an autotroph?
- A . bird
- B . frog
- C . deer
- D . snake
- E . tree
A family wants to plant a garden, but the soil around the house is mainly clay. Clay soil easily becomes saturated with water, cutting off the air supply needed by plants. Adding sand and peat moss can help plants grow in clay soil.
Which is the procedure for preparing the clay soil for planting?
- A . Dig deep holes and keep them filled with water for several weeks.
- B . Mix sand and peat moss with the soil while it is fairly dry.
- C . Plant only in sand or peat moss.
- D . Wait until midsummer before trying to plow or spade the soil.
- E . Wet the soil thoroughly for a week before trying to plow or spade it.
The digestive tract of an animal that eats meat is about four times the length of the animal’s body. In an animal that eats plants, the digestive tract is about twenty times the length of the animal’s body.
Which animal would be expected to have the longest digestive tract relative to its body length?
- A . dog
- B . cow
- C . house cat
- D . lion
- E . hawk
The battery of an automobile produces electricity from a chemical reaction. This electricity leaves the battery from a post called a terminal and is used in starting the engine. Sometimes a crusty deposit forms on the terminals, preventing the engine from starting. Simply cleaning off the deposit often restores the battery to operable condition.
Which effect does the deposit have on the battery terminals?
- A . conducts electricity
- B . improves spark plug firing
- C . causes hazardous sparks
- D . does not conduct electricity
- E . is caused by hard water
A cleaning agent contains ingredients listed in the figure below. Exhibit:
Which ingredient(s) would be the LEAST important in determining how well the cleaner can clean windows?
- A . ammonium hydroxide solution
- B . borax
- C . ammonium hydroxide and color
- D . borax and perfume
- E . perfume and color
The surface area of a log can be increased by splitting it into strips. Split wood with a larger surface area will burn much faster than a whole log. In much the same way, a sugar cube will dissolve much faster if its surface area is increased.
Which method will most increase the surface area of a sugar cube?
- A . Reshape the sugar granules into a ball.
- B . Divide the sugar cube into four square pieces.
- C . Break the sugar cube in half.
- D . Use a small round sugar tablet.
- E . Crush the cube into tiny fragments.
According to the information provided, what will happen to a straight metal bar when it is cooled?
- A . bend into a "u" shape
- B . become longer
- C . become more flexible
- D . become shorter
- E . remain the same
Each year, approximately 200 million tons of municipal solid waste are generated in the United States. Incineration (burning), recycling, landfills, reduce-reuse, and composting are all possible ways to reduce the amount of waste in this country. When selecting the best approach to this problem, officials must carefully consider the risks and benefits of each method.
Which disposal method will produce the most toxic air pollution?
- A . composting
- B . incineration
- C . landfills
- D . recycling
- E . reduce-reuse
If 1970―1997 trends continue, which statement could be predicted from the bar graph?
- A . Use of oil for energy production will decrease.
- B . Use of hydroelectric energy will increase.
- C . Use of coal for energy production will increase.
- D . Use of nuclear power will remain the same.
- E . Total energy use will decrease in the future.
Hot vapor from a cup of coffee forms droplets of liquid when the vapor passes over a cool spoon.
This condensation action is similar to which of the following?
- A . raindrops falling from the sky
- B . hail forming within a storm cloud
- C . a bathroom mirror fogging up
- D . steam rising from boiling water
- E . cold spray coming from a showerhead
A food chain is a way of showing food relationships among a group of organisms that share an environment. The illustration at the left represents a freshwater food chain.
What is most likely to happen if the supply of large fish in a pond is reduced by extensive fishing?
- A . Humans will eat more algae.
- B . The amount of algae will increase.
- C . The population of small fish will increase.
- D . Small fish will get smaller.
- E . Large fish begin to eat algae.
DDT is a toxic substance. The illustration below lists DDT levels in various organisms.
Which statement best explains why the amount of DDT is higher in the eagle than in the otherorganisms? Exhibit:
- A . DDT is more poisonous to birds than to other living organisms.
- B . The DDT in the small bird passes directly to the eagle.
- C . The eagle has a diet of animals and plants.
- D . DDT becomes more concentrated as it passes through the food web.
- E . Mice are the only animals on which the eagles feed.
Exhibit:
Based on the information and diagram, which statement represents the best observation?
- A . is the same during the entire time period
- B . slows down gradually
- C . is irregular during the time period
- D . speeds up during the time period
- E . is affected by the number of windows in the building
Exhibit:
Based on the information and diagram, which antibiotic would be most effective to use in treating the patient?
- A . the antibiotic in section D
- B . the antibiotic in section A
- C . the antibiotic in section B
- D . the antibiotic in section C
- E . The antibiotics in sections A and C are equally effective.
In order to remain healthy, the human body requires a certain level of vitamin D, which is synthesized in the body. Intestinal enzymes and sunlight convert cholesterol to vitamin D. People who do not spend much time in the sun can acquire vitamin D from the food they eat or from vitamin supplements.
Which person would benefit the most from ingesting a moderate amount of vitamin D in supplements or in the types of food eaten?
- A . coal miner who works underground
- B . mail delivery person
- C . marathon runner
- D . policeman who directs morning street traffic
- E . food vendor at a day soccer game
Wheat is the staple cereal for most of the world. Flour is made from the kernel of the wheat plant. The kernels are first separated from the plant stem and then broken apart by the milling process. The husk, the outer layer unusable for most purposes, is removed.
The wheat kernel (whole grain) has three main parts: germ, bran, and endosperm. The germ is especially rich in vitamin E, niacin, and riboflavin. The bran, a protective coating around the kernel, is also a rich source of nutrients and fiber. The endosperm, making up 83% of the kernel, is the soft inside portion containing starch and proteins.
Although the enrichment of white flour restores some of the lost nutrients, there are some vitamins and minerals that are lost in the refining process and not replaced. A valuable source of fiber is also lost.
Ling reads an article that states that many people don’t get enough fiber in their daily diet.
Which type of bread would be the best to recommend to Ling?
- A . whole wheat bread
- B . unenriched white bread
- C . enriched white bread
- D . sourdough bread
- E . French bread
By taking careful measurements, scientists have determined that the universe is expanding over time. Individual components of the universe, such as galaxies, continue to travel through space. This concept is sometimes represented by a balloon as shown below. Each dot on the balloon represents a part of the universe, such as a galaxy.
Based on the information and diagram, which statement best describes the way galaxies move through space over time?
- A . northward
- B . westward
- C . northwest
- D . farther apart
- E . closer together
Air is a mixture of gases, mostly nitrogen and oxygen, but it also contains a small amount of water vapor. Depending on its temperature, water can exist in any of the three states of matter.
In the diagram at the left, water droplets have formed on the outside of the can, and the can contains pieces of ice.
Based on the information and diagram, which statement regarding the droplets on the outside of the can is the most accurate?
- A . The can leaked water from the ice cubes as they melted.
- B . The ice in the can cooled the air around the can, causing the water droplet formation.
- C . Liquid on the can is CO2 from the exhaled air of the observers of the demonstration.
- D . Many more droplets would have appeared if a styrofoam cup had been substituted for the tin can.
- E . Many more droplets will form on the outside of the can on a windy day, when the air is less humid.
Why is algin used in a chocolate milk shake?
- A . provides a dark chocolate color
- B . makes the milk shake thick and creamy
- C . enhances the chocolate flavor
- D . makes the milk shake cold
- E . forces the milk shake to melt
An electromagnet is a magnet that can be turned on and off. It consists of a central metal core, such as iron, and many wrappings of wire around the metal core. An electrical current sent through the wire wrappings causes the formation of a magnetic field. There are several ways to increase the strength of an electromagnet: increasing the number of wrappings, increasing the current of electricity, making the wrappings closer together, or increasing the diameter of the core.
Five electromagnets are shown above. The electrical power source for each electromagnet is an ordinary flashlight battery.
Which electromagnet will produce the strongest magnetic field?
- A . A
- B . B
- C . C
- D . D
- E . E
Soil is formed when the rock at Earth’s surface weathers. Normally, soil develops into three layers, called horizons. The illustration below shows the A, B, and C horizons of a typical soil profile.
Based on the diagram, if the surface vegetation were removed, which would be the likely effect on the soil?
- A . The top 1 or 2 unprotected layers might wash away.
- B . The C horizon would be further buried.
- C . The A horizon would enlarge.
- D . The order of the horizons would be reversed.
- E . The B horizon would disappear entirely.
Scientists often place living organisms into related groups for the purpose of studying their physical characteristics. The diagram below shows five single-celled organisms.
Based on the above information and diagram, using the similarities of physical traits, which pair of organisms might be grouped for scientific study?
- A . A and D
- B . B and C
- C . B and E
- D . C and D
- E . C and E
When a cell, such as a red blood cell, is placed in pure distilled water, water will move into the cell, causing it to expand and burst. However, most plant cells, which are surrounded by a tough cellulose wall, will not burst when placed in pure distilled water.
This information indicates which of the following statements about cells?
- A . A plant cell cannot survive in pure distilled water.
- B . Water can dissolve a cellulose wall.
- C . A cellulose wall can resist the expansion of the cell.
- D . A cellulose wall is sometimes found around an animal cell.
- E . A plant cell absorbs more water than an animal cell.
In a suspension, two materials will mix together only temporarily. One material does not dissolve into the other, but stays suspended only until gravity pulls it down.
Which is an example of a suspension?
- A . colored water
- B . muddy water
- C . bleach
- D . ice water
- E . carbon dioxide and water
Some recipes suggest that certain foods, such as sauces and frostings, be prepared in a double boiler, such as the one shown at the left.
Which statement best describes the advantage of using a double boiler?
- A . The food in the top pan absorbs the heat energy from the water and keeps the temperature of both substances just below the freezing point of water.
- B . The food in the top pan will be cooked at a temperature several degrees higher than the boiling point of the water.
- C . As long as boiling water is in the bottom pan, the food will be cooked at the constant temperature of the boiling water.
- D . Less energy is required for the food to reach a boiling temperature than for the water to reach a boiling temperature.
- E . Twice as much food can be cooked using half the amount of energy.
Exhibit:
According to the article, about 5 percent of all children born have genes containing which component?
- A . harmful viruses that produce disease
- B . information that came from one parent only
- C . no genetic information
- D . information for red hair
- E . errors that have produced abnormalities
Making bread involves a chemical reaction. A chemical reaction involves starting materials (the reactants) and the substances produced (the products).
Which material is a product of this chemical reaction?
- A . yeast
- B . sugar
- C . carbon dioxide
- D . water
- E . starch
A spring can be compressed or stretched. The amount of force that is required for a spring to return to its original position depends on its "spring constant." If the spring constant is large, thespring is rigid and difficult to stretch or compress. If the spring constant is small, the spring stretches and compresses easily.
The diagram below depicts the amount of compression that results for spring A and spring B after equal force is applied to both.
Which situation requires a spring with the largest spring constant?
- A . A jack-in-the-box springs out of its box.
- B . A shock absorber spring keeps a truck from bouncing when it hits a pothole.
- C . A child plays with a "Slinky" spring.
- D . A spring holds staples in a stapler.
- E . The spring in a pinball game is used to release the ball.
A solid dissolves more rapidly if the solid’s surface area in contact with the water is increased.
Which would result in sugar dissolving more quickly in water?
- A . forming the sugar into large crystals
- B . grinding up the sugar to a powder
- C . using brown sugar rather than white sugar
- D . forming the sugar into a cube
- E . cooling the mixture of sugar and water
To begin a fission reaction, a neutron is shot at high speed into the nucleus of an atom of Uranium-235. This process releases a large amount of energy contained within the nucleus. The diagram above illustrates this process as well as possible by-products.
Based on the diagram and information, which statement best describes the fission reaction shown?
- A . The nucleus of Uranium-235 absorbs a neutron and gets bigger.
- B . The nucleus of Uranium-235 absorbs energy and gets smaller.
- C . The nucleus of Uranium-235 splits into smaller nuclei and releases energy.
- D . Two nuclei of Uranium-235 combine and release energy.
- E . Three neutrons combine and release energy.
Which of the following represents the approximate combined use (in quads) of natural gas and oil in 1997?
- A . 22
- B . 28
- C . 36
- D . 58
- E . 72
The left side of the brain dominates in verbal skills, reading, writing, and logical thinking. The right side of the brain is adept at space and pattern perception. While the right side does not express speech, the right side dominates in visual imagery and spatial relationships.
The left side of the brain would dominate in which of the following activities?
- A . using depth perception to park a car
- B . recognizing a person’s face
- C . recognizing a song on the radio
- D . having a conversation on the telephone
- E . looking at a picture in a museum
The death rate from heart disease fell more than 8 percent in just one year during the 1980s. Advances in public awareness of heart disease and in treatments for it are thought to be partially responsible for the decline. New heart drugs, a technique called angioplasty for clearing the arteries, and surgical advances have also assisted in reducing heart disease fatalities, as has increased interest in a healthy lifestyle and diet.
Which of the following was a contributing factor for the more than 8-percent decrease in heart disease mortality between 1988 and 1989?
- A . New kinds of heart medicine became available for public use.
- B . Sunscreen products were used more frequently.
- C . More people used the “buddy system” while engaging in strenuous activities.
- D . Exercise fads became less popular.
- E . More people regularly slept 8 hours per night.
Students in a biology class were asked to construct hypotheses about the relationship between air temperature and the number of times crickets chirp per minute. They listened to a tape of crickets chirping at six different temperatures. The students counted the number of chirps per minute and recorded their results, which are shown in the table below.
Which statement best describes the relationship between the number of chirps and the air temperature?
- A . The crickets will not chirp at 0° F.
- B . The crickets will not chirp when the temperature is above 81° F.
- C . As the temperature decreases, the number of chirps increases.
- D . As the temperature increases, the number of chirps increases.
- E . There is no relationship between the number of chirps and the temperature.
Nicotine patches are a popular smoking cessation method. Although they are effective for some people, not all nicotine patches work, and some doses work better than others. The graph below shows the effectiveness of nicotine patches for patients who participated in a 24-week study.
Based on the graph, Whatpercentage of patients receiving the 21-mg nicotine patches remained off cigarettes after six weeks?
- A . 57%
- B . 40%
- C . 27%
- D . 15%
- E . 5%
Blood typing is essentially a chemical reaction that provides data so that blood may be safely transfused from one person to another. The basic objective is to avoid “clumping” that could occur in the recipient when the wrong blood type is received. These “clumps” of red blood cells could block arteries or veins affecting the blood flow to critical body organs,
like the heart or the brain. Exhibit:
Based on the chart and the information, which blood type will not form clumps with either Anti-A reagent serum or the Anti-B reagent serum?
- A . Type A
- B . Type B
- C . Type AB
- D . Types A and B
- E . Type O
Since carbon dioxide dissolves in water to form an acid, an acid-base indicator such as bromthymol blue is used to track the acid concentration during plant photosynthesis and respiration. Bromthymol blue turns yellow in an acid solution and remains blue in a basic solution. The color change is reversible. A student used the following procedure to track carbon dioxide.
In an experiment, a student placed a solution of bromthymol blue into each of two flasks, inserted a drinking straw in each flask, and blew through the straw until the solution turned from blue to yellow. Carbon dioxide, a waste product in the student’s breath, caused the color change. The student then placed a small Elodea water plant in each flask and closed the flasks with rubber stoppers. Flask A was placed in bright sunlight, while flask B was
placed in the dark for 24 hours, as shown in the figure below.
After 24 hours, the bromthymol blue in flask A had turned back to blue, while in flask B it was still yellow.
If living things use oxygen and release carbon dioxide during respiration, what is the most probable reason that the atmosphere does not become depleted of oxygen and become filled with carbon dioxide?
- A . Plants replace the oxygen in the atmosphere and use carbon dioxide during photosynthesis.
- B . The atmosphere supplies large amounts of oxygen and absorbs large amounts of carbon dioxide.
- C . Carbon dioxide in the atmosphere breaks down in sunlight to release oxygen and water.
- D . Carbon dioxide is used by many invertebrate animals in place of oxygen during respiration.
- E . Plants don’t use oxygen from the atmosphere in the dark, but they do use carbon dioxide.
A home built on the California coast was once 150 yards from the shore. Now it is only 75 yards away.
Which process is most likely responsible for this change?
- A . erosion
- B . evaporation
- C . glaciation
- D . sedimentation
- E . subsidence
Animal populations are regulated by a variety of natural factors. Five of these factors are:
✑ competition―A struggle among rival organisms results when available resources
(for example, food or shelter) are limited. ✑ predation―Many animals pursue and eat other animals as prey. ✑ disease―In overcrowded populations, the buildup of waste products contributes to
the easy spread of disease. ✑ stress―In some populations, overcrowding can lead to hormonal disorders, which can cause abnormal behavior, thereby limiting the population. ✑ natural disaster―The occurrence of storms, floods, and earthquakes can significantly affect a population’s size.
✑ During the Middle Ages, the human population of Western Europe was severely reduced by a combination of unsanitary conditions and the abundance of flea-infested rats that spread the plague.
Based on the information provided, which of the following factors was responsible for the population reduction?
- A . competition
- B . predation
- C . disease
- D . stress
- E . natural disaster
A physical change is a change that occurs in a substance without the formation of a different substance. In a chemical change, new substances are formed.
Which situation is an example of a chemical change?
- A . burning a stack of papers
- B . melting snow
- C . boiling water
- D . breaking glass
- E . chopping wood
The nightshade family of plants includes more than 2000 species of herbs, shrubs, and small trees. Plants with edible parts include the potato, tomato, eggplant, and red pepper. Some nightshade members such as jimsonweed and belladonna contain poisonous substances. Tobacco and petunias are also in the nightshade family.
Which of the following most accurately describes the entire group of plants in the nightshade family?
- A . poisonous plants
- B . edible plants
- C . no economically important species
- D . no agriculturally important plants
- E . a large variety of species
A contour line is a line passing through points with the same altitude above sea level. A steep slope is represented by closely spaced contour lines; widely spaced contour lines show a more gradual incline.
A topographic map displays these contour lines and helps outline the shape of the landscape locating hills, cliffs, and depressions.
Based on the topographic map at the left, if a person wants to travel on level ground as much as possible, which would be the easiest path between points A and B?
Exhibit: Exhibit
- A . A C D C C C B
- B . A C E C F C B
- C . A C C C B
- D . A C C C F C B
- E . A C F C C C B
A person who takes medication in capsular form would be ingesting materials produced by which algae?
- A . green algae
- B . brown algae
- C . golden-brown algae
- D . red algae
- E . green algae and brown algae
Using new, advanced methods of biotechnology, scientists can produce copies of genes of one species and insert them into the chromosomes of another species. The resulting transgenic plants offer potential advantages that are unobtainable through conventional methods.
A gene that is active against corn borers is inserted into corn plants.
When the plants reach maturity, which of the following outcomes might be expected?
- A . The plants will resist corn borers.
- B . The bacteria will infect the plants.
- C . The corn plants will be taller.
- D . The plants will wither and die.
- E . The corn will have a better flavor.
Work is done on an object when a force is applied, causing the object to move.
Which example best illustrates this scientific idea?
- A . hitting a ball with a bat
- B . sitting on a chair
- C . standing in place
- D . holding a box E. pushing against a wall
A spontaneous process is a physical or chemical change that occurs by itself. The change requires no input of work or energy in any form.
Which of the following everyday occurrences results from a spontaneous process?
- A . water boiling
- B . iron rusting in moist air
- C . hydrocarbon emissions from gasoline combustion
- D . water freezing
- E . snow melting
Transpiration is the evaporation of water produced during photosynthesis from the parts of a plant exposed to air, especially from its leaves. The rate of transpiration varies among species of plants, as seen in the table below.
Which statement best explains why the transpiration rate of a cactus is so much lower than that of a rose bush and a dogwood?
- A . The cactus has adapted to dry climates through greatly reduced leaf surfaces.
- B . The cactus contains parasitic insects that are consuming the water in the plant’s roots.
- C . The rose and the dogwood are water plants, so water cannot evaporate from their surfaces.
- D . The dogwood transpires more than the rose because the dogwood’s roots are deeper.
- E . The cactus is not a plant, so it does not produce water during photosynthesis.
Temperature affects how well gases and solids dissolve to form solutions. Gas solubility increases with decreasing temperature. Cold water can hold more oxygen than warm water.
Fish require dissolved oxygen in the water for respiration. During the hot summer, Allan goes fishing at a nearby lake.
Based on the information, which statement indicates where and why Allan would find the most fish?
- A . shady areas because there is less dissolved oxygen gas in cool water
- B . sunny areas because there is no dissolved oxygen gas in warm water
- C . shady areas because there is more dissolved oxygen gas in cool water
- D . sunny areas because there is more dissolved oxygen gas in warm water
- E . both shady and sunny areas because the amount of dissolved oxygen gas in water is not changed by temperature
Wild rabbits in Alaska have short ears, whereas those found in Arizona have long ears. For the Alaskan rabbits, this is an adaptation to which of the following?
- A . amount of precipitation
- B . meager food supplies
- C . number of predators
- D . parasitic fungi
- E . cold temperatures
A tsunami is an unusually large ocean wave, which is sometimes formed by earthquakes. The height of a tsunami increases as it approaches shore. In the open ocean, tsunamis can travel at 300 to 400 miles per hour.
Based on this information, which statement must be true?
- A . Tsunamis have killed millions of people in this century.
- B . The height of a tsunami located 100 miles offshore is low.
- C . Tsunamis are sometimes found in small lakes.
- D . Tsunamis travel at 100 miles per hour.
- E . There are no known causes of tsunamis.
A pet shop wants to install a fountain that contains live fish. The temperature in the facility is kept at 67° F (19° C) throughout the year.
The following chart gives the preferred temperature range for certain fish species.
Which fish would be most likely to thrive in this environment?
- A . trout
- B . bass
- C . catfish
- D . salmon
- E . perch
In the gear arrangement shown at the left, turning gear A will turn gear B in the direction marked with arrows.
Which of the following will cause gear B to turn more rapidly?
- A . turning gear A more slowly
- B . putting a gear of smaller diameter at B
- C . using a much more dense metal in gear B than gear A
- D . using gears that have an equal number of “teeth”
- E . putting a gear of larger diameter at B
Based on the information and graph, which statement provides the best conclusion?
- A . Increasing the amount of salt in the solution has no effect on bean plant growth.
- B . As salt concentration of the solution increases, bean plant growth decreases.
- C . As salt concentration of the solution increases, bean plant growth increases.
- D . The salt concentration of the solution affected only the growth of Group V.
- E . The salt concentration had the greatest effect on the growth of Group III.