1
A researcher investigated two groups of fruit flies. Population A was kept in a 0.5-L container. Population
B was kept in a 1-L container.
1. The manipulated variable was the
A. number of flies.
B. time in days.
C. difference in time per group.
D. size of the containers.
2. Which of the following is a logical inference based on the contents of the graph?
A. The flies in Group B were healthier than those in Group A.
B. A fly population with more available space will grow larger than a population with less space.
C. If Group B were observed for 40 more days, the size of the population would double.
D. In 40 more days, the sizes of both populations would decrease at the same rate.
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2
Once a month, a pet owner recorded the mass of her puppy in a table. When the puppy was 3 months old,
she started to feed it a “special puppy food” she saw advertised on TV.
5. According to the table, which statement is true?
A. The puppy's mass increased at the same rate for each month shown.
B. The puppy's increase in mass during month 4 was greater than 4 kg.
C. The puppy added more mass during month 2 than during month 3.
D. The puppy added more mass during month 3 than during month 2.
6. All of the following statements about the pet owner's study are true EXCEPT
A. The owner made quantitative observations.
B. The owner used the metric system.
C. The owner recorded data.
D. The owner conducted a controlled experiment.
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Which of the following statements about the image shown below is NOT an observation?
A. The insect has three legs on the left side.
B. The insect has a pattern on its back.
C. The insect's pattern shows that it is poisonous.
D. The insect is green, white, and black.
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4
Study the graph to answer the questions that follow.
The enzyme catalase speeds up the chemical reaction that changes hydrogen peroxide into oxygen and
water. The amount of oxygen given off is an indication of the rate of the reaction.
9. Based on the graph, what can you conclude about the relationship between enzyme concentration and
reaction rate?
A. Reaction rate decreases with increasing enzyme concentration.
B. Reaction rate increases with decreasing enzyme concentration.
C. Reaction rate increases with increasing enzyme concentration.
D. The variables are indirectly proportional.
10. Which concentration of catalase will produce the fastest reaction rate?
A. 0%
B. 5%
C. 15%
D. 20%
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5
The diagrams below represent the amount of biomass and the numbers of organisms in an ecosystem.
6. What is true about the pyramid of numbers?
A. First-level consumers compose the greatest number of individuals.
B. There are more third-level consumers than second-level consumers.
C. There are more producers than first-level consumers.
D. none of the above
7. What can you conclude based on the two pyramids?
A. The producers are probably small, like single-celled algae in a body of water.
B. The producers are probably large, like trees in a forest.
C. No reasonable conclusion can be drawn from the information given.
D. none of the above
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6
From 1960 to 1995, scientists recorded the concentration of carbon dioxide in the atmosphere and the
average temperature at a remote site in Hawaii. Their data are shown in the graph.
8. Based on the graph, which of the following is most likely?
A. Carbon dioxide levels and overall temperature will increase.
B. Carbon dioxide levels will soon decline.
C. Warm temperatures are increasing the carbon dioxide concentration.
D. The variables are indirectly proportional.
9. Which of the following would most likely cause an increase in atmospheric carbon dioxide?
A. increased biomass
B. a faster rate of photosynthesis
C. melting of the polar ice caps
D. increased burning of fossil fuels
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The graph below represents
A. carrying capacity.
B. exponential growth.
C. logistic growth.
D. limiting factors.
5
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Use the graph below to answer the following questions.
7. What is true of the time interval marked E in the graph?
A. Carrying capacity has been reached.
B. Birthrate is greater than death rate.
C. Population is growing.
D. The population is declining.
8. Which time interval(s) in the graph shows exponential growth?
A. D and E
B. A and B
C. C and D
D. E only
9. Which time interval(s) in the graph depicts the effects of limiting factors on population?
A. A only
B. A and B
C. C, D, and E
D. C and D
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6
9
Examine the food web below and determine which of the following organisms would accumulate the
highest levels of a chlorinated pesticide.
A. hawk
B. rabbit
C. frog
D. grasses
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10
Use the information below to answer the questions that follow.
Fire ants first arrived in the United States in 1918, probably on a ship traveling from South America to
Alabama. The maps show the geographic location of the U.S. fire ant population in 1953 and 1994.
9. Which statement is true about fire ants in the United States?
A. They reproduce slowly.
B. They are a native species of the United States.
C. They are an invasive species.
D. Their numbers are declining.
10. By 2010, fire ants are likely to
A. occupy Florida only.
B. have reached their carrying capacity.
C. die out.
D. have spread to a larger area.
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11
In an experiment, plant cells were placed in sucrose solutions of varying concentrations. The rate at which
the plant cells absorbed sucrose from the solution was then measured for the different concentrations. The
results are summarized in the graph below.
7. In this experiment, there was a positive sucrose uptake. Sucrose probably entered the cells by means of
A. endocytosis.
B. osmosis.
C. active transport.
D. phagocytosis.
8. The graph shows that as the concentration of sucrose increases from 10 to 30 mmol/L, the plant cells
A. take in sucrose more slowly.
B. take in sucrose more quickly.
C. fail to take in more sucrose.
D. secrete sucrose more slowly.
9. Which statement is best supported by information in the graph?
A. The rate of sucrose uptake increases at a constant rate from 0 to 30 mmol/L.
B. The rate of sucrose uptake decreases at a varying rate from 0 to 30 mmol/L.
C. The rate of sucrose uptake is less at 25 mmol/L than at 5 mmol/L.
D. The rate of sucrose uptake is constant between 30 and 40 mmol/L.
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12
Which organelle contains chlorophyll?
A.
B.
C.
D.
Which equation best summarizes the process of photosynthesis?
A.
B.
C.
D.
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13
Several drops of concentrated pigment were extracted from spinach leaves. These drops were placed at
the bottom of a strip of highly absorbent paper. After the extract dried, the paper was suspended in a test
tube containing alcohol so that only the tip of the paper was in the alcohol. As the alcohol was absorbed
and moved up the paper, the various pigments contained in the extract separated as shown in the diagram
below.
7. Which pigment traveled the shortest distance?
A. yellow-orange
B. yellow
C. blue-green
D. yellow-green
8. A valid conclusion that can be drawn from this information is that spinach leaves
A. use only chlorophyll during photosynthesis.
B. contain several pigments.
C. contain more orange pigment than yellow pigment.
D. are yellow-orange rather than green.
9. In which organelles would most of these pigments be found?
A. vacuoles
B. centrioles
C. mitochondria
D. chloroplasts
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14
The graph below shows the rate of alcoholic fermentation for yeast at different temperatures.
8. What is the relationship between the rate of fermentation and temperature?
A. The rate of fermentation continually increases as temperature increases.
B. The rate of fermentation continually decreases as temperature increases.
C. The rate of fermentation increases with temperature, then it rapidly decreases.
D. The rate of fermentation decreases with temperature, then it increases.
9. Which statement could explain the data shown in the graph?
A. The molecules that regulate fermentation perform optimally at temperatures above 30°C.
B. The yeast begins releasing carbon dioxide at 30°C.
C. The yeast cannot survive at temperatures above 30°C.
D. The molecules that regulate fermentation perform optimally below 10°C.
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15
The spindle fibers of a dividing cell were labeled with a fluorescent dye. At the beginning of anaphase, a
laser beam was used to stop the dye from glowing on one side of the cell, thereby marking the fibers, as
shown in the second diagram. The laser did not inhibit the normal function of the fibers.
10. This experiment tests a hypothesis about
A. how chromosomes migrate during cell division.
B. how fluorescent dyes work in the cell.
C. the effect of lasers on cells.
D. the effect of lasers on fluorescent dye.
11. The diagram shows that the spindle fibers
A. shorten on the chromosome side of the mark.
B. lengthen on the chromosome side of the mark.
C. shorten on the centriole side of the mark.
D. lengthen on the centriole side of the mark.
12. A valid conclusion that can be drawn from this experiment is that
A. centrioles pull chromosomes toward the poles of the cell.
B. chromosomes do not migrate in the presence of dye.
C. chromosomes migrate only when treated with dye.
D. chromosomes travel along the fibers toward the poles of the cell.
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16
Genes A, B, C, and D are located on the same chromosome. After calculating recombination frequencies,
a student determines that these genes are separated by the following map units: C–D: 25 map units; A–B:
12 map units; B–D: 20 map units; and A–C: 17 map units.
7. How many map units apart are genes A and D?
A. 5
B. 8
C. 10
D. 12.5
8. Which gene map best reflects the student's data?
A.
B.
C.
D.
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17
A scientist analyzed several DNA samples from exons to determine the relative proportions of purine and
pyrimidine bases. Her data are summarized in the table below.
8. Which sample(s) support(s) the base pairing rules?
A. Sample A only
B. Sample B only
C. Sample C only
D. Samples A and C
9. If the scientist had analyzed mRNA rather than DNA, what percentage of uracil would you expect to
find in Sample B?
A. 10
B. 25
C. 35
D. 40
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A researcher chooses a plasmid with a gene that confers resistance to the antibiotic ampicillin. She
isolates and tries to insert a human gene that codes for a protein into the plasmid. Next, she transforms
bacteria using the plasmid. She then cultures the new bacteria on a nutrient medium containing ampicillin.
3. What can the researcher conclude about the bacteria that grow on the nutrient medium?
A. They are resistant to ampicillin.
B. They contain recombinant DNA.
C. They contain a human gene.
D. all of the above
4. Which of the following would indicate that the bacteria contain the human gene?
A. They produce the human protein encoded by the human gene.
B. They produce ampicillin.
C. both A and B
D. neither A nor B
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19
A student traced a widow's peak hairline in her family. Based on her interviews and observations, she
drew the following pedigree:
5. Which pattern(s) of inheritance are consistent with the pedigree?
A. sex-linked
B. complete-dominance
C. codominance
D. incomplete-dominance
6. What are the probable genotypes of the student's parents?
A. Mother—Ww; Father—ww
B. Mother—ww; Father—ww
C. Mother—WW; Father—Ww
D. Mother—Ww; Father—Ww
7. The student does not have a widow's peak hairline, but her sister does. What are the girls' probable
genotypes?
A. Student—Ww; her sister—ww
B. Student—WW; her sister—Ww
C. Student—ww; her sister—Ww
D. Student—ww; her sister—ww
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The diagram below best illustrates
A. Lamarck's theory of evolution.
B. Darwin's theory of evolution.
C. Malthus's principles.
D. Lyell's theory about past changes.
If coat color in a rabbit population is a polygenic trait, which process might have produced the graph
below?
A. stabilizing selection
B. disruptive selection
C. directional selection
D. genetic equilibrium
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21
The graphs show the changes in crab color at one beach.
9. What process occurred over the 40-year period?
A. artificial selection
B. sexual selection
C. stabilizing selection
D. disruptive selection
10. Which of the following is most likely to have caused the change in distribution?
A. A new predator prefers dark-tan crabs.
B. A new predator prefers light-tan crabs.
C. A new beach color makes medium-tan crabs the least visible to predators.
D. A new beach color makes medium-tan crabs the most visible to predators.
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22
The graph shows the radioactive decay of an isotope. Use the information in the graph to answer the
questions that follow.
7. The half-life of thorium-230 is 75,000 years. How long will it take for 7/8 of the original amount of
thorium-230 in a sample to decay?
A. 75,000 years
B. 225,000 years
C. 25,000 years
D. 70,000 years
8. The half-life of potassium-40 is about 1300 million years. After four half-lives have passed, how much
of the original sample will be left?
A. 1/16
B. 1/16 × 1300 million grams
C. ¼
D. ¼ × 1300 million grams
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23
Which organism belongs in the kingdom Animalia?
A.
B.
C.
D.
20
The figure below shows the presumed relationships between three insect taxa.
What is true about these three groups of insects?
Roaches and mantids share a more recent common ancestor than do roaches and termites.
Roaches and mantids share a more recent common ancestor than do mantids and termites.
Termites, roaches, and mantids share a common ancestor.
A. I only
B. II only
C. I and III only
D. I, II, and III
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24
Use the graph below to answer the questions.
10. At which point in the graph does the number of living bacteria increase at the greatest rate?
A. Between hours 2 and 4
B. Between hours 4 and 6
C. Between hours 6 and 8
D. Between hours 10 and 12
11. Which is the most likely reason for the decrease in bacteria shown?
A. The temperature of the bacterial culture was too high after 8 hours.
B. The bacteria stopped reproducing after 8 hours.
C. More nutrients were added to the culture at regular intervals.
D. Waste products from the bacteria accumulated in the nutrient solution.
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25
Use the graph below to answer the following questions.
10. It is estimated that there are at least ten actual cases of malaria for every one reported and shown in
the graph. Based on this estimate, how many millions of cases of malaria were there in Africa in 1991?
A. 9
B. 5
C. 50
D. 90
11. Based on the data in the graph, the incidence of malaria is
A. declining in Africa.
B. increasing in Southeast Asia.
C. both A and B
D. none of the above
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26
Ripe grapes are covered with a grayish film called “bloom,” which contains yeasts and sometimes other
microorganisms. A group of students prepared three test tubes of fresh, mashed grapes. They heated two
of the test tubes to the boiling point, then cooled them. They inoculated one of these test tubes with live
yeast. They incubated all three test tubes at 30°C for 48 hours and then examined the test tubes for signs
of fermentation—the presence of bubbles and alcohol. Their data are summarized in the table below.
9. What is the independent variable in the students' investigation?
A. presence of live yeast or other microorganisms
B. light
C. bubbles
D. odor of alcohol
10. What is the dependent variable in the students' investigation?
Boiling
Odor of alcohol
Presence of bubbles
A. boiling
B. odor of alcohol
C. presence of bubbles
D. both B and C
11. What can you conclude, based on the students' results?
Uninoculated, boiled grape mash does not seem to ferment over a 48-hour period.
Boiled grape mash that contains live yeast undergoes fermentation.
Grape mash does not ferment unless live yeast is added.
A. Uninoculated, boiled grape mash does not seem to ferment over a 48-hour period.
B. Boiled grape mash that contains live yeast undergoes fermentation.
C. Grape mash does not ferment unless live yeast is added.
D. both A and B
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27
A group of students placed a sprig of a conifer in a beaker of water. They measured the amount of oxygen
given off during a set period of time to determine the rate of photosynthesis. They changed the
temperature of the beaker using an ice bucket and a hot plate. Their data are summarized in the graph
below.
9. What is the independent variable in the students' investigation?
A. light intensity
B. temperature
C. plant growth
D. oxygen bubbles
10. Which variables should the students have held constant?
Plant type
Temperature
Light intensity
A. I only
B. II only
C. I and III only
D. II and III only
11. What can you conclude based on the graph?
A. The higher the temperature, the more oxygen bubbles are released.
B. There is an optimum temperature for photosynthesis in this species of conifer.
C. All plants are most efficient at 30°C.
D. The lower the temperature, the more oxygen bubbles are released.
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28
A student compared the average number of stomata on the top side and the underside of different plants.
Her data are summarized in the table.
9. What generalization can be made based on the data?
A. All plants have more stomata on the top side of their leaves than on the bottom side.
B. Plants have fewer stomata on the top side of their leaves than on the bottom side.
C. Some plants have more stomata on the top side of their leaves than on the bottom side.
D. The number of stomata varies greatly from plant to plant.
10. Pumpkins, tomatoes, and beans all grow in direct sunlight. Assuming the plants receive plenty of
water, stomata on the lower surface of their leaves
A. are always closed.
B. are usually clogged with dust.
C. are unlikely to close at night.
D. stay open during daylight hours.
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29
A scientist measured the average time it took different fruits to fall 1 meter (m) from the parent tree.
Assume that for every second a fruit falls, it is carried 1.5 m away from the parent tree.
10. Which fruit was carried the farthest from the parent tree?
A. silver maple
B. Norway maple
C. white ash
D. red oak
11. According to these data, what benefit does a winged fruit have over an acorn?
A. It is lighter.
B. It is heavier.
C. It will travel farther.
D. none of the above
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30
The results of an experiment are summarized in the art below. Use information from the art to answer the
questions that follow.
9. Which of the following can be concluded from the results of this experiment alone?
A. Hormones are produced in the growing tips of plants.
B. Plants grow toward the sun because of compounds produced in their stems.
C. Agar blocks contain a variety of plant compounds.
D. Compounds produced in shoot tips can cause stems to bend.
10. Based on your knowledge of plant hormones, which of the following best explains the results of this
experiment?
A. Auxins produced in the shoot tip caused cell enlargement in the growing stem.
B. Cytokinins produced in the shoot tip caused cell enlargement in the growing stem.
C. Auxins produced in the shoot tip caused lateral bud growth.
D. Cytokinins caused the shoot tip to die.
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31
A biology student is investigating the relationship between cricket chirps and temperature. She catches a
cricket and places it in a jar. She leaves the jar outside, and each day she measures the number of chirps
during a 15-second period. At the same time, she records the outside temperature near the cricket. Her
data for a 5-day period are shown below.
9. At which of the following temperatures would a cricket be most likely to chirp 9 times in 15 seconds?
A. 2°C
B. 10°C
C. 18°C
D. 0°C
10. What can the student conclude from this experiment?
A. Crickets cannot chirp more than 31 times in 15 seconds.
B. The number of chirps decreases when the temperature decreases.
C. Crickets never chirp more than 31 times every 15 seconds.
D. The number of chirps increases when the temperature decreases.
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32
The graph below shows the growth rate of a hypothetical coral species under different conditions. Use this
information to answer questions 1 and 2.
1. This coral grows best at depths of
A. 5–10 m; 20°C
B. less than 10 m; 15°C
C. less than 10 m; 28°C
D. more than 10 m; 21°C
?
and a temperature of
?
.
2. Which of the following statements best explains the trend shown in the graph?
A. The growth rate of the coral increases as the depth below the water surface increases.
B. At temperatures of 15°C or above, the growth rate depends only on temperature.
C. Corals cannot grow below 30 m.
D. This coral grows best from 18° to 23°C.
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33
A biology student has two samples of earthworms, as shown below. The student knows that because the
worms' body temperature changes with the environment, the worms in Sample A have a higher body
temperature than those in Sample B. The student uses a stereomicroscope to count the number of
heartbeats per minute for three worms from each sample.
9. Look at the student's two samples. What can you conclude?
A. Sample A is the control.
B. Sample B is the control.
C. Either sample can serve as the control.
D. This is not a controlled experiment.
10. The student finds that the worms from Sample A have a faster heart rate than the worms from Sample
B. What conclusion can be drawn?
A. The worms in Sample A are healthier than the worms in Sample B.
B. A decrease in body temperature corresponds to an increase in heart rate.
C. There is no relationship between body temperature and heart rate.
D. A decrease in body temperature corresponds to a decrease in heart rate.
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34
An ecologist collected data about the number of frogs that inhabit a certain pond each year. In addition, he
collected data about the total amount of rainfall in that area each spring. The data are shown in the table.
10. In what year were the most frogs observed?
A. 1996
B. 1997
C. 1998
D. 1999
11. Which statement is best supported by the data?
A. The number of frogs increased each year.
B. The number of frogs decreased each year.
C. The number of frogs increased or decreased based on whether it is an odd or even numbered year.
D. The number of frogs in the pond increased as the amount of rainfall increased.
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35
An experiment was conducted to see how air temperature affects a snake's ability to move. The
experimenter placed the snake a fixed distance away from a piece of food and recorded the air
temperature. Then, she recorded the time it took for the snake to reach the food. She repeated the
experiment four times. Each time, the experimenter changed the air temperature. The data are shown
below.
9. At what air temperature did the snake reach the food the fastest?
A. 4°C
B. 10°C
C. 21°C
D. 27°C
10. What conclusion can be drawn from the data?
A. As the air temperature increased, the time it took for the snake to reach the food increased.
B. As the air temperature decreased, the time it took for the snake to reach the food increased.
C. Air temperature had no effect on the time it took the snake to reach the food.
D. Snakes are ectotherms.
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36
Radioactive substances found in living things decay at a specific rate over time. The rate at which a
substance decays is measured by its half-life. A half-life is the amount of time it takes for half a
radioactive sample to decay. For example, the half-life of carbon-14 is 5770 years. Use the bar graph to
answer the following questions.
8. How much carbon-14 would remain in an 11,540-year old fossil?
A. 25 percent
B. 35 percent
C. 50 percent
D. 60 percent
9. A paleontologist determines that a particular fossil has 1/8 of the amount of carbon-14 that was present
at the time the organism died. How old is the fossil estimated to be?
A. 5770 years
B. 11,540 years
C. 23,080 years
D. 34,620 years
10. Scientsts cannot accurately detect the amount of carbon-14 in a fossil when more that 1/16 of the
carbon-14 has decayed. Which of these fossils could NOT be dated accurately using carbon-14?
A. a 2500-year-old fossil
B. a 5000-year-old fossil
C. a 10,000-year-old fossil
D. a 75,000-year-old fossil
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37
Refer to the following cladogram:
8. Which characteristic is shared by humans, wallabies, and trout?
A. placenta
B. notochord
C. amniotic egg
D. four limbs
9. Which animals in the cladogram have the closest evolutionary relationship?
A. humans and wallabies
B. humans and lizards
C. humans and lampreys
D. humans and salamanders
10. A valid conclusion from this cladogram is that
A. salamanders, trout, and lampreys all have a backbone.
B. four limbs appeared in vertebrate evolution before the notochord.
C. humans and lampreys share a common ancestor.
D. salamanders have amniotic eggs.
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38
A researcher observed sedge warblers during breeding season. She charted the number of different songs
a male bird sang compared to the time it took him to pair with a mate. The graph shows her data.
9. The researcher was trying to find out whether there is a correlation between
A. the number of a male bird's songs and the number of offspring.
B. the number of a male bird's songs and his attractiveness to females.
C. a male's age and the number of songs he sings.
D. a male's age and when he mates.
10. What can you conclude based on the graph?
A. Males prefer females that do not sing.
B. Females prefer males that do not sing.
C. Males prefer females with a large number of songs.
D. Females prefer males with a large number of songs.
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39
The table below lists the blood alcohol concentration (BAC) as alcohol consumption increases. Use the
information in the table to answer the questions that follow.
9. How many drinks in one hour would cause a 63-kg person to have a BAC percentage of 0.08?
A. 1
B. 2
C. 3
D. 4
10. If a 54-kg person had 3 drinks in one hour, what would his or her BAC percentage be?
A. 0.06
B. 0.08
C. 0.09
D. 0.11
11. If a 72-kg person had 4 drinks in two hours, what would his or her BAC percentage be?
A. 0.03
B. 0.05
C. 0.08
D. 0.13
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40
Osteoporosis is a disease characterized by the loss and weakening of bone tissue. One possible
explanation for this condition is that as people age, the mineral content of their bones decreases. To assess
this hypothesis, the bone mineral content of 250 men and 250 women was measured. The data are shown
below.
8. At which age do women show the lowest bone mineral content?
A. 50–59 years
B. 60–69 years
C. 80–89 years
D. 90–95 years
9. A valid conclusion that can be drawn from this graph is that, on average,
A. women lose more bone mineral content as they age than men do.
B. men lose more bone mineral content as they age than women do.
C. women and men lose the same bone mineral content as they age.
D. women gain bone mineral content as they age.
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41
Use the data in the table to answer the questions that follow.
A student is studying the effect of temperature on the action of an enzyme in stomach fluid. The enzyme
digests protein. An investigation was set up using five identical test tubes, each containing 40 mL of
stomach fluid and 20 mm of glass tubing filled with gelatin. After 48 hours, the amount of gelatin
digested in each tube was measured in millimeters. The results for the five test tubes are shown in the
table.
7. Which is the manipulated (independent) variable in this investigation?
A. gastric fluid
B. length of glass tubing
C. temperature
D. time
8. An additional test tube was set up that was identical to the other test tubes and placed at a temperature
of 15°C for 48 hours. What amount of digestion would you expect to occur in this test tube?
A. less than 3.0 mm
B. between 3.0 and 4.5 mm
C. between 4.5 mm and 8.0 mm
D. more than 8.0 mm
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42
A researcher measured the concentrations of HIV and T cells in 120 HIV-infected patients over a period
of 10 years. Her data are summarized in the graph.
8. Why does the T cell concentration decrease after two years?
A. HIV dies off after two years.
B. HIV destroys T cells.
C. T cells produce toxins.
D. An inflammatory response occurs.
9. What happened to the HIV concentration over years 2 through 9?
A. It stayed about the same, then suddenly increased.
B. It stayed about the same, then suddenly decreased.
C. It steadily increased.
D. It steadily decreased.
10. What is probably responsible for the change in HIV concentration during the first year?
A. immune response
B. inflammatory response
C. passive immunity
D. HIV vaccination
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