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There are over 2000 kinds of edible insects in the world, and they are becoming an increasingly popular source of protein. One cup of cricket flour contains over 28 grams of protein. The building blocks of the protein in cricket flour are*
Which list contains only abiotic conditions that might be found in a pond ecosystem?*
Protein synthesis is accomplished primarily by the interaction of which two cell structures?*
Identical twins were separated at birth and raised by two different families. Years later, one twin was a physically fit member of the cross-country team, and the other twin was overweight with slightly higher-than-normal blood pressure. The differences in these twins could be explained by the fact that*
The diagram below represents various factors in an area.
The diagram best represents*
Traits are passed from parents to offspring. These traits are determined by*
In which cell structure is energy extracted from nutrients?*
The diagram below represents a food web in a pond ecosystem.
Two carnivores in the food web are*
Dodder plants consist of tangled masses of yellow, leafless vines and contain few chloroplasts. The vines twist around and grow into the stems of other plants and absorb water and nutrients from them. Which statement best describes this relationship?*
Two kittens in a litter are genetically different from each other and from their parents. These genetic differences are most directly due to*
A genetic change that occurs in a body cell of a mouse will not contribute to the evolution of the species because*
Scientists who have examined the fossil record have noted that some species have changed very little over long periods of geologic time. The lack of change in such organisms is most likely because*
Doctors often use certain medications to treat infections. A few people have a reaction to some of these medications, such as itching, swelling, or trouble breathing. This is an example of*
Organisms that live on land rarely compete for*
Orcas are endangered whales. Only about 80 individuals remain off the coast of Washington State. Salmon are a source of food for orcas. Some individuals are proposing that four dams in Washington State be removed so that habitat areas for salmon will be increased. Those opposed to the dam removals say that the dams provide low-cost hydroelectric power and positively influence the local economy.
This situation is an example of*
A small lizard spends the morning hours lying in the sunlight until its body temperature rises. Later on in the day, the lizard rests in a shady area until its body temperature cools. This type of behavior is important to*
Sexually reproducing organisms pass on genetic information as a*
Some viruses attack cells by attaching to their outer covering, entering, and taking over their genetic “machinery.” Viruses are able to invade cells after first attaching to their*
Gene mutations can be caused by many things. These mutations are biologically important because they*
Maintaining a rich variety of genetic material that may lead to discoveries useful to humans can be ensured by*
Many bacteria and fungi are important in the environment because they*
Which statement best describes a characteristic of the carrying capacity of an ecosystem?*
The Venus flytrap is a plant that has a unique system by which it traps and breaks down its prey. Unsuspecting insects land on the leaf and touch tiny hairs located on the leaf, triggering the leaf to close around the prey.
The substance responsible for breaking down the Venus flytrap’s prey most likely contains*
It may be harmful when people compete to see who can hold their breath the longest under water. Without oxygen, brain cells*
Students did an experiment comparing the activity of four different enzymes, A, B, C, and D. The results are represented in the graph below.
A valid conclusion based on the information in the graph is that*
Euglena are unique single-celled organisms. Depending on the physical conditions present in their aquatic environment, Euglena can act as either producers or consumers.
Euglena will most likely act as consumers when placed in an environment that has*
The diagram below illustrates the movement of glucose across a cell membrane.
Which two processes are most directly represented in this diagram?*
The diagram below shows the relationship between the snowshoe hare and the lynx. The snowshoe hare is prey of the lynx.
The populations of the two species increase and decrease based on the numbers of each species present. This relationship is an example of*
Following fertilization, a zygote divides and soon becomes a multicelled embryo with many different cell types, as represented below.
Which statement best explains this development?*
The diagram below represents changes that take place within the human body.
The diagram represents*
An experiment is carried out to determine how different pH values of soil will affect the growth of tomato plants. In this experiment, the dependent variable could be the*
Using microscopes he constructed in the 1600s, Antonie van Leeuwenhoek discovered a new microscopic world. His discoveries paved the way for the development of the microscopes used today and for many important biological breakthroughs.
Which statement best describes van Leeuwenhoek’s work?*
Base your answers to questions 33 and 34 on the information below and on your knowledge of biology.
Anabolic steroids are hormones that affect muscle growth. Many athletes take synthetic anabolic steroids, in hopes of developing larger muscles so they can perform better at their sport. These hormones can act like the hormone testosterone. When men take an excess of anabolic steroids, they can have an increase in feminine features. This is due to the fact that the excess of these chemicals signals the male body to stop producing testosterone.
This signal in the male body to stop producing testosterone is an example of*
One reason why anabolic steroids can imitate the hormone testosterone is because*
Base your answers to questions 35 and 36 on the information in the chart below and on your knowledge of biology.
How does the ability to produce 3000 to 6500 eggs benefit the species?*
One explanation for the timing and length of the leopard frog breeding season is that it occurs*
Sailors in the past may have heard the greeting from a passing ship, “Avast ye scurvy dogs.” This greeting would be a reference to a disease known as scurvy, which is due to inadequate intake of vitamin C. Which row in the chart below correctly identifies the cause of this disease and a possible treatment for it?
Male birds of two different species living on the same island have developed different mating behaviors, as shown in the table below.
Which statement is best supported by information in the table?*
In a DNA molecule, if 38% of the molecular bases are C (cytosine), what percent of the bases are T (thymine)?*
An increased demand for soybeans has led to an increase in converting native forests and grasslands to fields for growing soybeans. One negative consequence of this environmental change has been*
In the 1660s, Flemish physician Jan van Helmont grew a small willow tree in a pot of soil. He added only water to the pot. At the end of five years, he found that the tree had gained 75 kilograms, but there was very little change in the mass of the soil. Van Helmont concluded that the plant gained weight directly from the water. We now know that this conclusion is only partially correct because, in addition to water, photosynthesis also requires*
Base your answers to questions 42 and 43 on the illustration below and on your knowledge of biology. The illustration shows two methods of reproduction, method A and method B.
Which statement regarding these methods of reproduction is correct?*
Which process takes place in both method A and method B?*
Corals are a group of organisms that live in shallow, warm areas of the world’s oceans. Coral reefs are composed of a hard material that is produced by these small coral animals, and is then colonized by photosynthetic organisms called Zooxanthellae. These plant-like organisms generate sugars that are used by their animal partners for food and are needed for the survival of the coral.
State one possible reason that coral reefs exist only in shallow waters. *
Base your answers to questions 45 through 47 on the information and data table below and on your knowledge of biology.
Measles is a highly contagious viral disease. Infected people first experience a fever, cold-like symptoms, and a rash. Several complications can develop, such as ear infections, diarrhea, pneumonia, encephalitis (swelling of the brain), and death. Prior to the widespread use of the measles vaccine in the 1960s, it is estimated that 3–4 million people were infected every year. The Centers for Disease Control and Prevention declared measles eliminated in the United States in 2000. This was accomplished, in part, due to a highly effective vaccination program. However, since 2016 the disease has made a comeback, and there has been an increase in measles cases in recent years.
Directions: Using the information in the data table, construct a line graph on the grid below, following the directions below.
Mark an appropriate scale, without any breaks in the data, on each labeled axis. *
Plot the data on the grid. Connect the points and surround each point with a small circle. 
The reason for the dramatic decline in the number of measles cases from the 1960s to 2010 in the United States was because the vaccine*
Base your answers to questions 48 and 49 on the information below and on your knowledge of biology.
The line graphs below represent trends in prey fish populations for each of the five Great Lakes.
Identify in which of the Great Lakes you would expect to see the greatest increase in the number of predatory fish in 2008 and 2009. Support your answer. *
Which statement is correct, based on the information in the diagram?*
Base your answers to questions 50 and 51 on the information below and on your knowledge of biology.
Barley Gene Lowers Emissions From Rice
Over half the people on the planet eat rice as a staple food. Growing rice emits methane, a potent greenhouse gas—to the tune of 25 million to 100 million tons of methane every year, a notable contribution to human-caused greenhouse gas emissions…
…When rice paddies are flooded, methane-producing bacteria thrive on the carbohydrates secreted by rice roots in the oxygen-free soils. The rice plant itself acts as a conduit [pathway], transmitting methane from the soil into the atmosphere…
Source: Times Tribune 7/23/15
Scientists have incorporated a barley gene into a type of rice and produced rice plants that have much lower methane emissions. It is most likely that the scientists incorporated the barley gene into the rice, producing a new variety, using the process of*
Now that the scientists have developed this new variety of rice plant, identify one method that could be used to produce large quantities of only these beneficial plants. *
Base your answer to question 52 on the information and diagram below and on your knowledge of biology. The diagram represents the energy relationships in a forest ecosystem.
Based on the information in the diagram, only some of the available energy is transferred from one energy level to the next. State what happens to the rest of the energy. *
Base your answers to questions 53 through 55 on the information below and on your knowledge of biology.
The European glow-worm (Lampyris noctiluca) is an insect and a member of the firefly family. Males are ordinary-looking beetles with brown wings. Females are much larger, don’t have wings, glow, and look like a large larva. Adult glow-worms usually live for less than two weeks. They don’t eat, focusing all their energy on finding a mate. The glow-worm has few enemies. Its body contains a poison that protects it from predators and its light warns would- be attackers that it is not safe to eat.
Greenish light glows from the end of a female’s abdomen, an organ called the lantern, for up to several hours each night. There are great differences in the size of the female lanterns. In an experiment, scientists found that females with larger lanterns glowed brighter, and the brightest females laid the most eggs. The diagram below shows three different glow-worms.
Describe one way that a glowing abdomen helps the glow-worm increase its reproductive success. *
Explain why increased light pollution in areas where glow-worms are found could affect glow-worm populations. *
Although the females glow at night and are easily seen by predators, they have few enemies. State one characteristic that protects them from predators. *
Base your answers to questions 56 through 58 on the information below and on your knowledge of biology.
Throughout its long history, Earth has warmed and cooled time and again. Climate has changed when the planet received more or less sunlight due to subtle shifts in its orbit, as the atmosphere or surface changed, or when the Sun’s energy varied. But in the past century, another force has started to influence Earth’s climate: humanity. …
…What has scientists concerned now is that over the past 250 years, humans have been artificially raising the concentration of greenhouse gases in the atmosphere at an ever- increasing rate, mostly by burning fossil fuels, but also from cutting down carbon-absorbing forests. Since the Industrial Revolution began in about 1750, carbon dioxide levels have increased nearly 38 percent as of 2009 and methane levels have increased 148 percent. …
Other than the issues mentioned in the passage, state one action that humans could take to slow down the rate of global warming. *
Other than global warming, state one specific effect on the environment if the human activities mentioned in the passage continue. *
On November 4, 2016, the Paris Agreement brought many nations into a common cause to combat climate change and adapt to its effects on a global level. State one reason why climate change needs to be addressed globally as well as locally. *
Base your answers to questions 59 through 61 on the information and photograph below and on your knowledge of biology. The photograph shows a handful of croton nuts.
The Power of the Croton Nut
The croton nut tree grows in East Africa. It produces a nut that is inedible [to humans], and the tree itself was considered of little use except for firewood. The trees grow over vast areas, and many of these areas have been deforested to get rid of the trees and to make more land available for agriculture.
Recently, scientists and engineers in Kenya have been able to crush the nuts and obtain oil, which can be used as a less expensive substitute for diesel fuel, a nonrenewable fossil fuel. The leftover nut pulp can be processed and sold for fertilizer, compressed into biofuel briquettes for use in cooking stoves, or converted into feed for chickens, making the commercial use of the croton nut a zero-waste process.
Explain why the use of croton nut oil represents an advantage over the use of conventional diesel fuel. *
Describe one environmental benefit of maintaining croton forests rather than cutting them down to use the land for farming. *
Explain why the commercial use of the croton nut is considered a zero-waste process. *
Base your answers to questions 62 and 63 on the information below and on your knowledge of biology.
DDT: A “Miracle Pesticide”
DDT is a pesticide developed during World War II that successfully killed insects, such as mosquitoes, that were a large problem for our soldiers in the Pacific. DDT was also very effective for preventing insect damage to crops, so it was considered, at the time, to be a “miracle pesticide.”
Soon, however, scientists noticed that DDT was negatively affecting other animals and being passed along food chains. For example, some birds accumulated large amounts of DDT in their tissues, which caused them to lay eggs with weakened shells that broke before hatching.
Rachel Carson, a marine biologist and author, became concerned about the use of pesticides and their negative effects on the environment. Carson began to write books and speak about the dangers of pesticides. Her actions eventually led to many changes in our use of pesticides and proved valuable to protecting our environment and people from the negative effects that were being discovered about pesticides.
Some scientists began to suspect that DDT was not the “miracle pesticide” that it was originally thought to be. State one possible hypothesis that these scientists may have proposed to begin their research to find out more about DDT. *
All scientific explanations are tentative and subject to change or improvement. Explain how this statement relates to the scientific thinking about DDT. *
Base your answers to questions 64 through 67 on the information and graph below and on your knowledge of biology. The graph shows the change in the blood glucose level of one person after eating a cookie.
Explain why most human cells require a supply of glucose. *
State one specific response of the body to the increase in blood glucose level that would account for the changes that begin about 30 minutes after eating the cookie. *
Describe how the line representing blood glucose would change if the body could not take corrective actions to return this system to normal levels after eating a cookie. *
Based on the data and information provided, state whether or not it would be valid to conclude that bananas supply more glucose than cookies. Support your answer. *
Base your answer to question 68-71 on the information below and on your knowledge of biology.
It is estimated that every year more than 15 million babies are born too early. The lungs of these premature infants are often immature and easily damaged. Premature births happen for a variety of reasons—some known and some unknown. Those that are known include infections and conditions such as diabetes and high blood pressure. Scientists are researching what causes premature births, in an attempt to develop solutions to prevent them.
Scientists are also working on the development of an artificial placenta. At the University of Michigan, five premature lambs were placed in artificial placentas and kept alive for weeks. During this time, each lamb’s blood was circulated through its artificial placenta.
Discuss how the development of an artificial placenta is an important step in the study of premature births. In your answer, be sure to:
• explain why it would be harmful for a human mother’s blood to pass across the placenta and into the
• state how an artificial placenta would be of benefit to the lungs of premature infants 
• explain why the lambs’ blood must be filtered as it circulates through the artificial placenta 
• state one reason why premature lambs were likely used as model organisms in this study rather than
As the rate of environmental change has increased over the last 50-100 years, there has been an increase in extinction rates. Lower reproductive rates seem to have also contributed to this increase in extinctions.
Describe one possible reason for an increased extinction rate in populations of species with a lower rate of reproduction. *
Base your answers to questions 73 and 74 on the information and Universal Genetic Code Chart below and on your knowledge of biology.
The messenger RNA sequence that codes for the amino acid chain TYR–ARG–GLY–VAL–ALA–LEU is*
The messenger RNA sequence that is most likely to produce a functional protein is*
Base your answers to questions 75 and 76 on the information below and on your knowledge of biology.
A forensic scientist is trying to determine if the plant pieces found on a burglary suspect match the plants found outside a home that was robbed. The suspect had plant pieces in the hood of his jacket as well as green stains on the knees of his jeans.
In order to compare the composition of the pigments on the suspect’s jeans to the pigments of the plants at the home, the forensic scientist should use*
The evidence that would be most convincing in determining that the plant pieces found in the suspect’s hood matched the plants outside the home that was robbed would be if they both had the same*
Base your answers to questions 77 and 78 on the information below and on your knowledge of biology.
The diagram below represents a lab setup. The artificial cell (dialysis tube) contains a starch solution and the beaker contains a solution of starch indicator and water. The setup is left undisturbed for twenty minutes.
Identify one molecule, present in this setup, that will be able to pass through the dialysis tubing. *
Describe one observation that could be made that would confirm that the molecule you identified in question 77 had passed through the membrane. *
Base your answer to question 79 on the diagram below and on your knowledge of biology.
A new finch is found to have a diet of worms and caterpillars. Identify one finch from the diagram that would have a beak most similar to the new finch. Support your answer. 
A student was given forceps (tweezers) as his tool in the Beaks of Finches lab. Circle which type of food he would likely pick up most easily – small seeds or large seeds. Support your answer. 
Small seeds Large seeds
Base your answer to question 81 on the information and diagram below and on your knowledge of biology.
A student added equal volumes of water to two different beakers. He then added blue food dye to one and yellow to the other. Next, he placed a white paper towel across the two beakers so that it went down into the liquid and connected the two beakers.
After 20 minutes, the section of paper towel connecting the two beakers had turned color. The towel most likely turned green as a result of the*
Base your answers to questions 82 and 83 on the information and photograph below and on your knowledge of biology.
A Close Relative of the Elephant
A hyrax is an animal that has been called a rock rabbit and looks like a guinea pig. Fossil records show that hyraxes first appeared on Earth approximately 37 million years ago. As they evolved, some became mouse-sized, while some were the size of a horse. Some eventually adapted to marine life and are related to manatees, and some became grazers and are related to elephants.
A section of the mammalian evolutionary tree is shown below.
Which number would indicate the most recent common ancestor of the hyrax, elephant, and manatee on the section of this mammalian evolutionary tree?*
Identify one type of molecular evidence that could have been used to develop this mammalian evolutionary tree, and describe one specific way that the evidence could have been used to construct the tree. 
Base your answers to questions 84 and 85 on the information and graph below and on your knowledge of biology.
During a lab experiment a student took his resting pulse rate, counting 23 beats in 20 seconds. The student then exercised for several minutes. The student’s pulse was taken immediately after the exercise, and then every minute for 6 minutes. The graph below shows changes in the pulse rate after the exercise was completed.
What was the student’s resting pulse rate in beats per minute? 
State one biological explanation for how the pulse rate increase benefited the student as he exercised. *