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How do cells in the ovary detect a hormone from the brain?*
Single-celled organisms are able to maintain internal stability because they*
A similarity between humans and many other multicellular animals is that they*
In order to enter cells and be useful to the body, starch must be*
The increase of certain types of gases in the atmosphere has contributed to the problem of global warming. All these gases are*
Several goldfish were kept in a small aquarium for several years. The fish grew to be approximately 6 centimeters long in the first year, and after that, growth in length stopped. These fish were later transferred to a large pond. In the pond, the goldfish grew much larger, reaching lengths of around 25 centimeters. Which statement provides the best explanation for the increased growth of the fish in the pond?*
Autotrophs might survive when heterotrophs cannot, because autotrophs are able to*
The inability of sperm cells to move normally could prevent the production of offspring by interfering with*
Which type of pathogenic microbe causes AIDS?*
The diagram below represents a technique used to produce carrots.
Which reproductive process determines the traits present in the cluster of cells?*
The diagram below represents a scientific technique in use today.
Scientists have used this technique to*
DNA is able to control cellular activities most directly by regulating the process of*
Which statement describes an effect of natural selection on a species?*
Maple leaf beetles and willow leaf beetles are named for the type of tree where they live and reproduce. They look identical to each other when observed, but experiments have shown that willow beetles would starve before eating maple leaves. This is an example of specialization that would directly reduce*
Which event would most likely cause a change in a genetic sequence in an organism?*
During the process of cellular respiration, energy is released from*
A new vaccine was developed and then tested on a large sample of individuals. This new vaccine will be considered effective if it helps prepare the body to fight future invasion by*
Which expression correctly represents a repro- ductive process that usually occurs in humans where 2n is equal to the number of chromo- somes in each body cell?*
One effect of uncontrolled diabetes is that the blood might develop an acidic pH. As a result, cells may not be able to regulate their internal pH. Within these cells, this could cause a disruption of the function of biological catalysts known as*
A Native American saying states that, “We do not inherit the land we live on from our grandparents, we borrow it from our grandchildren.” This saying is an attempt to make us understand that*
Cells of the immune system are able to respond to the presence of invading organisms because they recognize the*
Typhoid fever, a disease that causes headaches, digestive upset, and a high fever, is caused by the bacterium Salmonella typhi. Typhoid can be spread from person to person by contaminated water or food or by a lack of cleanliness. Since the 19th century, the number of individuals infected with this disease has decreased. Which statement best explains why the number of people with this disease and other bacterial diseases has decreased over the last 100 years?*
Deforestation most directly results in*
In the California Mojave Desert, an energy company is building a large solar-power facility. It is expected to produce enough power for 140,000 homes and also cut carbon dioxide emissions by 500,000 tons a year. The facility will be built on 4,050 acres of wildlife habitat, which is near a protected refuge for a species of desert tortoise. The decision to build this power plant is most likely based on*
As a result of human activity, a significant percentage of the coral reefs in the oceans have been damaged. One-third of marine fish species depend on coral reefs for survival. Many of these fish might die. The most direct cause of the death of these fish would be*
Which statement best describes the role of decomposers?*
Many scientists are worried about some of Earth’s finite resources because humans are*
Many communities have started programs to dispose of evergreen trees after the holiday season. These programs allow individuals to bring these trees to be shredded, and the resulting chips are spread around parks and recreational areas as mulch. These programs benefit the environment by*
Modern dogs are direct descendants of the gray wolf. They first appeared about 130,000 years ago. Today, there are about 150 different breeds of domestic dog, a few of which are shown below.
The great variety of modern dogs can best be explained by*
The diagram below shows an alteration that occurred during the replication process of a portion of a gene. The numbers identify the locations of specific bases in the sequence.
This alteration is most likely the result of*
Base your answers to questions 31 and 32 on the diagram below and on your knowledge of biology. The diagram represents a food web.
What do the arrows in the diagram represent?*
Which statement correctly describes interactions between organisms in this ecosystem?*
Humans have altered ecosystems by activities that are sometimes deliberate and sometimes accidental. In the United States, humans have altered ecosystems by introducing invasive species that outcompete native species. Which activity resulted in the accidental introduction of an invasive species?*
The diagram below represents a specialized cell located in the root of a plant. The arrows in the diagram indicate the movement of molecules of oxygen and water into the cell.
Which row in the chart below correctly identifies the process responsible for the movement of each type of molecule represented in the diagram?
Base your answer to question 35 on the graph below and on your knowledge of biology. The graph shows the level of gene expression of five different genes in normal and cancerous cells.
Which statement is a valid inference that can be made based on the data in this graph?*
The cells of some organisms contain both chloroplasts and mitochondria. Which statement describes what would happen in these cells if they were moved from a light environment to a dark one?*
In the spring of 2010, there was a catastrophic explosion on an ocean oil drilling rig, causing millions of gallons of oil to be released into the Gulf of Mexico. Many organisms died due to the thick sludge in their habitat. However, in some organisms, such as shellfish, the oil stuck to tissues inside their shells. Which statement expresses a major concern of environmentalists about the accumulation of the oil in certain organisms in the Gulf of Mexico ecosystem?*
Base your answers to questions 38 and 39 on the information and data table below and on your knowledge of biology.
Fertilized eggs containing embryos from the same species of alligator were incubated at different temperatures. The sex of the hatched offspring is shown in the table below.
A review of this data could lead to the conclusion that*
The percent of surviving females at 32°C from the original number of eggs incubated was*
Base your answers to questions 40 and 41 on the graph below and on your knowledge of biology. The graph shows the growth of a population of rabbits in a specific ecosystem.
Which environmental factor could have caused the change indicated at A?*
Over a period of time, the location of the dashed line would move from location B to location C on this graph if*
Base your answers to questions 42 and 43 on the diagram below and on your knowledge of biology. The diagram represents the effect of two chemical substances, A and B, in maintaining the level of glucose in the blood in humans.
The interaction of substances A and B is an example of*
Which statement is correct regarding the substances involved in these interactions?*
Two views through a compound light microscope of a wet-mount slide preparation of cells are shown in the photographs below.
Which procedure was most likely followed to obtain view B? *
Base your answers to questions 45 through 47 on the data table below and on your knowledge of biology. The data table shows the concentration of estrogen in picograms per milliliter (pg/mL) in the blood of a woman over the course of 28 days.
Directions: Using the information given in the data table, construct a line graph on the grid following the directions below.
Mark an appropriate scale, without any breaks, on the axis labeled “Concentration of Estrogen.” *
Plot the data for concentration of estrogen on the grid. Surround each point with a small circle and connect the points. 
The concentration of estrogen at day 8 is closest to*
Base your answers to questions 48 and 49 on the word equations below and on your knowledge of biology. The equations represent two biochemical processes that occur in living organisms. The letter X represents a molecule produced from process 1.
Process 1: oxygen + glucose → carbon dioxide + water + X
Process 2: carbon dioxide + water → oxygen + glucose
Identify the molecule represented by letter X in process 1. *
Which process occurs in the cells of a green plant leaf?*
Base your answers to questions 50 through 53 on the graph below and on your knowledge of biology. The graph shows some events associated with the reproductive cycle of human females.
Which sections of the graph represent structures affected directly by the hormones shown?*
According to the graph, on which day is the egg released from the ovary? 
Which section of the graph shows the location where the zygote would most likely become implanted and develop? 
Identify another human reproductive hormone that is not shown on this graph. 
Base your answers to questions 54 and 55 on the information below and on your knowledge of biology.
Different plant species require different amounts of direct sunlight in order to flower. A student designed an experiment to determine the length of exposure to direct sunlight necessary for a specific plant species to produce flowers. The student collected the data below.
0 hours, 0% with flowers; 9 hours, 0% with flowers
1 hour, 0% with flowers; 5 hours, 90% with flowers
3 hours, 80% with flowers; 7 hours, 10% with flowers
Organize the data collected, from shortest to longest length of exposure, in the data table below. 
At the end of the experiment, the student stated that if plants are exposed to more hours of daylight, they will always produce a greater percentage of flowers. Is this a valid conclusion? Support your answer. *
Base your answers to questions 56 and 57 on the information below and on your knowledge of biology.
Decline in the Amphibians
Declines in amphibian species, such as frogs, toads and salamanders, might affect the ways in which ecosystems function. Amphibians prey on many types of small organisms that survive by consuming leaf litter (leaf material on the ground of ecosystems). These small organisms include animals such as earthworms, centipedes, millipedes, pill bugs, and many species of insects. In turn, amphibians are preyed on by fish, herons, chipmunks, turkeys, foxes, coyotes, and other animals.
Human activities often cause a reduction in the size of amphibian populations. As amphibian populations are reduced, the organisms that are preyed on by amphibians increase in number. As the populations of small forest organisms increase, the amount of leaf litter decreases. The decrease in the amount of leaf litter on the forest floor may have negative effects on the forest ecosystem.
Identify one human activity and describe how that activity could directly or indirectly lead to a reduction in amphibian populations. *
State one possible effect an increase in the amount of leaf litter on the forest floor would have on the amphibian population. Support your answer. *
Base your answers to questions 58 and 59 on the information below and on your knowledge of biology.
Female Shark Reproduced Without Male DNA, Scientists Say
A hammerhead shark that gave birth in a Nebraska aquarium reproduced without mating, a genetic analysis shows.
This form of asexual reproduction, called parthenogenesis, has been found in other vertebrate species, including some snakes and lizards. But this is the first time it has been documented in a shark.…
Instead, the female shark’s own genetic material combined during this process of cell division that produces an egg. A cell called the secondary oocyte, which contains half the female chromosomes and normally becomes the egg, fused with another cell called the secondary polar body, which contains the identical [amount of] genetic material….
Robert E. Hueter, director of the Center for Shark Research at the Mote Marine Laboratory in Sarasota, Fla., said the finding helped fill a gap in understanding parthenogenesis, which has been found to occur in most vertebrate lines except mammals, and until now, cartilaginous fishes like sharks….
“It’s a last-resort tactic that animals use when they absolutely can’t find another mate,” Dr. Hueter said.
Source: Henry Fountain, The New York Times, May 23, 2007
State why parthenogenesis is considered a form of asexual reproduction. *
Explain why parthenogenesis could prove to be harmful to the survival of this species if it were the only method of shark reproduction. *
Base your answers to questions 60 through 62 on the information below and on your knowledge of biology.
Ticks, such as deer ticks and dog ticks, feed on the blood of humans and other animals. Part of the feeding process involves the tick injecting its saliva to help make blood flow. In the process, they sometimes spread disease organisms to their host. Sometimes ticks get on clothing, and can remain there for a few days before actually biting their host.
A scientist found that ticks might be able to survive even when exposed to hot water and detergent in a washing machine.
Students designed the experiment below to test how well ticks survive a hot-water washing machine cycle with detergent. Note that some details of the design are incorrect.
Identify one error with the hypothesis. *
Explain why the students’ proposed data to be collected would not likely test what the students intended. *
Identify one error in the students’ design in the shaded area of the table and explain how the students should change the experiment to correct the error. 
Base your answers to questions 63 through 66 on the passage below and on your knowledge of biology.
The Return of the Large Blue Butterfly
In 1979, the Large Blue Butterfly was declared extinct in the United Kingdom, despite the efforts to protect the grasslands where it lived.
Research into the butterfly life cycle discovered the following facts. The butterflies lay their eggs on flowering thyme plants, and the caterpillars fall to the ground after they hatch. The young butterfly caterpillars have a “honey gland” on their posterior end, which, when stimulated by red ants, makes the caterpillars smell and wiggle like red ants. The red ants treat the butterfly caterpillars as ant grubs and carry them to their underground homes. The red ants keep looking after them and guard them, even though the caterpillars eat ant grubs for 10 months before flying away as adult butterflies in the spring.
The red ants live in fields of short grass. The grass is short enough to let the sun warm the soil. This is where the ants find and eat insects and plants. Rabbits had kept the grass short until the mid-1950s, when the rabbit populations were suddenly devastated by a viral disease. Additionally, farmers allowed pastures to get overgrown by not letting cattle graze on the grass. The red ants vanished when the taller grass increased the shade and cooled the soil.
A program was introduced to protect the pastures where the red ants nested. Their numbers came back. Populations of Large Blue Butterflies from Sweden were brought into the area, and now the Large Blue Butterfly is thriving again.
Describe one way humans have negatively influenced the ecosystem of the red ant. *
Describe one adaptation present in the butterfly caterpillars that enables the Large Blue Butterfly to survive. *
In the space below, construct a food chain consisting of at least three organisms, including a producer, that would be present in the ant ecosystem. *
Select one organism from the food chain you constructed and write it on the line below. State one way the removal of the organism you selected would affect another organism in the food chain. Support your answer. 
Base your answer to question 67-69 on the information and photographs below and on your knowledge of biology.
In addition to their use for hearing, ears contain many blood vessels that allow heat to escape into the air. Animals that live in warm climates tend to have ears with large areas exposed to the environment. Animals in cold climates have a more compact ear that keeps exposure to the environment to a minimum. The photographs below show a jackrabbit from desert regions of the southwestern United States and a fennec fox from northern Africa with large ears, and a snowshoe hare and an arctic fox with small ears.
Discuss how differences in ear size in these organisms might have occurred. In your answer, be sure to:
• explain how the size of these animals’ ears can help the animals survive in their environment 
• identify one process that most likely resulted in the animals in warm climates having large ears, while animals in cold climates have small ears 
• state how the overproduction of offspring in each species for many generations contributed to the presence of different ear sizes *
Base your answers to questions 70 and 71 on the information below and on your knowledge of biology.
Plasmodium, the world’s most lethal parasite, causes malaria. The parasite enters the bloodstream through a mosquito bite, hiding in the human liver before invading red blood cells. Ultimately, millions of infected blood cells explode at once, causing fever and death in 3 million people a year worldwide.
Source: Zimmer, February 12, 2001, “Animal Parasites – As Gross As It Gets,”
“Science World,” pg 11.
State one reason why Plasmodium is considered a parasite of humans. *
State one negative impact on humans when the use of pesticides for mosquitoes is decreased. *
If a large quantity of herbicide, a chemical that is designed to kill weeds, were accidentally spilled into a large lake, it could endanger all the organisms living in the lake. State one way the effects of killing the weeds in the lake could be destructive to populations of fish and other animals. *
Base your answers to questions 73 and 74 on the diagram below and on your knowledge of biology. The diagram represents evolutionary relationships among some primates.
Which statement best describes a relationship between the common ancestor and the other organisms in the diagram?*
A line representing an organism that is closely related to leaf monkeys and that evolved at about the same time as the gibbons would be drawn beginning at point*
The parents of a new baby believe they brought the wrong child home from the hospital. Gel electrophoresis was performed using DNA samples from the parents and the child. A section of the gel electrophoresis results is shown below.
Which conclusion is valid based on the gel electrophoresis results?*
The extremes of dry and wet weather of the Galapagos Islands cause the food supply to constantly change. During dry years, the food is mainly large, hard seeds, and finches with large beaks are found in greater numbers.
Which statement best explains this observation?*
Base your answers to questions 77 and 78 on the information below and on your knowledge of biology.
Three students took their pulse rates in beats per minute (bpm) while sitting in class. The results are shown in the data table below.
State one reason why the pulse rates were not the same for all three students, even though they were all resting at the time. *
What is the average pulse rate, in bpm, for this group of students? 
Base your answers to questions 79 and 80 on the information and data table below and on your knowledge of biology.
In an experiment, three plants of the same species were grown in each of six identical pots. The heights of the plants were measured when growth began. Each of the pots was watered every day with salt solutions of different concentrations. The data for the experiment are shown in the table below.
State the effect of increasing the percent of salt in the solution used to water the plants on the average final height of the plants in groups A through D. *
State one way diffusion was involved in the cause of death of the plants in groups E and F. *
In an experiment to determine the effect of exercise on pulse rate, a student checks his pulse rate before and after exercising for several minutes. The purpose of checking his pulse rate before exercising is that it*
What is an advantage of a change in pulse rate after exercising?*
The diagrams below represent seeds taken from a carrot plant and seeds taken from plant species 1, 2, and 3.
Which species would be expected to be most similar to the carrot? Support your answer. *
Other than having a variation in beak characteristics, describe another variation in a finch species that could promote survival of an individual bird. Support your answer. *
Identify or describe one tool used in “The Beaks of Finches” lab, and explain why the special features of this beak represented either an advantage or a disadvantage in the competition. 
Advantage or disadvantage: