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One characteristic of all living things is that they*
The diagram below represents interactions between organisms in a stable ecosystem.
Which statement correctly describes organisms in this ecosystem?*
Due to overfishing, the number of fish in the ocean could drastically decrease. This will cause*
Which substance can enter a cell by diffusion without having to be digested?*
A single-celled organism is represented below.
Structure X carries out a function most similar to which structure in a human?*
Parrots are tropical birds. However, in some areas of New York City, some parrots have been able to survive outdoors year-round. These parrots survive, while most others cannot, due to*
Changing one base in a gene could have the most direct effect on the*
An alteration of genetic information is shown below.
A-G-T-A-C-C-G-A-T → A-G-T-G-A-T
This type of alteration of the genetic information is an example of*
The table below shows adaptations in two organisms.
The presence of these adaptations is most likely the result of*
The diagram below represents an activity that occurs in the human body.
This diagram best illustrates*
In which row in the chart below is a human action correctly paired with its environmental impact?
A laboratory technique is represented in the diagram below. Letter A represents a process.
Which specific chemicals are needed to success- fully carry out the process shown at A?*
The diagram below represents genetic material.
The expression of the section labeled X may be modified by*
Characteristics that are harmful to a species tend to decrease in frequency from generation to generation because these characteristics usually*
Which situation results in a characteristic that is inheritable?*
Which statement best describes bat populations in a stable ecosystem?*
Which characteristic of a geographic region would have the greatest influence on the type of ecosystem that forms in that region?*
A scientist claimed that he had cloned a guinea pig to produce two offspring, a male and a female. The claim is not valid because*
The major function of the placenta is to*
During the process of photosynthesis, energy from the Sun is converted into*
A pesticide that kills an insect by interfering with the production of proteins in the insect would most directly affect the activity of*
When two different bird species temporarily occupy the same niche, they would most likely*
Which group would most likely be represented in a food chain?*
Which statement describes a similarity between all enzymes, antibodies, and hormones?*
The diagram below represents a cycling of materials.
Which row in the chart below shows the substances represented by X and Y?
Over a long period of time, the stages represented in the diagram below were each present in a particular ecosystem.
After a forest fire, what is the most likely order in which these stages appeared?*
A ski resort installed a wind turbine similar to those represented below to supply some of its energy needs.
This turbine was most likely installed because wind power is*
Which activity would reduce biodiversity in a forest ecosystem?*
An increase in the amount of ultraviolet light entering the atmosphere through holes in the ozone layer will most likely*
Many scientists suggest that billions of years ago, life on Earth began with*
Base your answers to questions 31 and 32 on the information below and on your knowledge of biology.
Diabetes is a condition characterized by elevated blood sugar levels. One form of diabetes occurs when insulin fails to properly regulate blood sugar levels. Complications from diabetes can include nerve cell damage and poor blood flow, especially in the feet and legs. In individuals with diabetes, wounds usually take longer than normal to heal.
The failure of a cell to react in a normal manner to insulin is most likely the result of a problem with*
One reason for the change in wound healing time in a diabetic is that*
The diagram below represents a series of events that occur in living cells.
Which molecule is indicated by X?*
Base your answers to questions 34 and 35 on the diagram below and on your knowledge of biology. The letters in the diagram indicate structures present in a human male.
Which structure produces the male hormone responsible for characteristics such as muscle development, deep voice, and gamete production?*
What change would occur immediately if both structures labeled B were damaged or blocked?*
Which term refers to the ecological niche of many bacteria and fungi in an ecosystem?*
The diagram below represents a model of a biological process that occurs in humans at normal body temperature, 37°C.
Increasing body temperature to 40°C would interfere most directly with the rate of function of structure*
Base your answers to questions 38 and 39 on the diagram below and on your knowledge of biology. The diagram represents the reproductive cycle of a squirrel species with 40 chromosomes in each zygote.
A process that could be represented by A is*
A liver cell in this species of squirrel would have*
A sample of body cells and samples of sex cells received from four members of a species are screened for the presence of a specific gene mutation. The results of the gene-testing procedure conducted on the cells are shown in the table below.
Which species member would be unlikely to pass the gene mutation on to its offspring?*
Base your answers to questions 41 through 43 on the diagram below and on your knowledge of biology. The diagram represents an energy pyramid for an ecosystem in the Australian outback.
Wombats are classified as herbivores because they can*
Which two organisms could have a predator-prey relationship?*
Dingos are an introduced species in Australia that are outcompeting many native species. Which of the cur- rent environmental problems most likely resulted directly from the introduction of dingos to Australia?*
Base your answers to questions 44 through 48 on the information and data table below and on your knowledge of biology.
Daphnia (water fleas) are sensitive to many changes in pond ecosystems. For this reason they are often used in bioassays, tests in which organisms are exposed to various levels of a chemical to determine what levels are safe. The results of these tests determine whether or not the chemical being tested will affect other pond organisms.
An experiment was designed to determine the toxicity of different salt solutions on cultures of daphnia. Five fish tanks were each filled with the same amount of water containing different concentrations of salt. Ten daphnia were placed into each tank. After 48 hours, the number of daphnia that had survived and the number of daphnia that had died in each tank were recorded and the percent mortality was calculated. The results of the experiment are shown in the data table below.
Directions: Using the information in the data table, construct a line graph on the grid on the next page, following the directions below.
Label the x-axis. Be sure to include units. *
Mark an appropriate scale, without any breaks, on each axis. *
Plot the data for mortality on the grid. Surround each point with a small circle and connect the points. 
Which salt concentration was most toxic to the daphnia in this experiment?*
Which salt concentration is most likely closest to the concentration of salt found in the natural environment of this species of daphnia? Support your answer. 
Salt concentration:_______________________ g/L*
Base your answers to questions 49 through 51 on the information below and on your knowledge of biology.
Beware of Dust Mites
Quietly lurking within our mattresses, under our beds, and inside sofas and carpets are creatures too small to be seen with- out a microscope. Dust mites are arthropods closely related to spiders, scorpions, and ticks. They feed on the dead skin cells regularly shed by humans and their animal pets. The average human sheds about 10 grams of dead skin a week. Cats and dogs create even more dander for dust mites to eat. The mites also eat pollen, fungi, and bacteria. They do not drink water but absorb it from the air.
Dust mites do not carry diseases and are harmless to most people. It’s their bathroom habits that make some of us itch and sneeze. Many people develop severe allergies to dust mite feces
(wastes). If you lie on a rug where dust mites live, you might develop itchy red bumps on your skin. Breathe in dust containing their feces and you might have more serious symptoms, such as difficulty breathing or a severe asthma attack.
Dust mites thrive in warm, humid environments — eating and nesting in dust-collecting bedding, fabric, and carpet. Think about this! A typical mattress can contain anywhere from 100,000 to 10 million dust mites. Nearly 100,000 dust mites can live in one square yard of carpet.
During a process called sensitization, a person’s immune system mistakenly identifies the inhaled dust mite waste as an invader. The next time the person is exposed to the dust mite waste, the immune system launches an allergic reaction.
The immune system of an individual who is allergic to dust mite waste produces*
An allergic reaction occurs when the immune system*
State one way, other than using a pesticide, that an individual could decrease the number of dust mites present in his home. *
A small village that is heavily infested with mosquitoes was sprayed with an insecticide once a week for several months. Changes in the size of the mosquito population are shown in the graph below.
State one way that the population of mosquitoes present 7 months after spraying differs genetically from the population of mosquitoes present before the spraying began. *
The diagram below shows a branching “tree” representing the evolution of ten different groups of organisms alive today.
Identify the group of organisms that is most closely related to the Arthropoda group. Support your answer. 
Group of organisms:_______________________*
Base your answers to questions 54 and 55 on the information and graph below and on your knowledge of biology. The graph contains information about an ecosystem.
The graph below shows the carrying capacities of an ecosystem for three different species, 1, 2, and 3, that inhabit an area and the actual population sizes of these three different species in the area.
Identify which species population would most likely have the greatest competition among its members. Support your answer using information from the graph. 
Explain how an ecosystem can have three different carrying capacities. *
Base your answers to questions 56 through 60 on the information below and on your knowledge of biology.
A chemical known as fertex affects external fertilization of sea urchin eggs. An experi- ment was set up using three tanks to investigate the effect of fertex. Each tank had a different concentration of fertex: 1%, 2%, and 3%. Ten sea urchin eggs and 2 mL of sea urchin sperm were added to each of the three tanks. A fourth tank was set up as a control.
State one way the contents of the control tank would differ from the contents of the three experimental tanks. *
Identify two factors that must be kept the same in all four tanks. 
State one way to improve the validity of the experimental results. *
Identify the independent variable in the experiment. *
State one example of the type of data that should be collected during the experiment. *
Base your answer to question 61-63 on the information below and on your knowledge of biology.
In order to enroll in most schools, students must be vaccinated against certain viral diseases, such as mumps. Even with these vaccinations, many students still suffer from other diseases. Discuss how a vaccination works and why some students still become infected with other diseases. In your answer, be sure to:
• identify what is present in a vaccine that stimulates an immune response 
• describe how a vaccine protects against disease 
• state why a student vaccinated against mumps can still be infected by the pathogens that cause other diseases, such as chicken pox *
Recently, the bison population in Yellowstone National Park declined significantly. This was due in part to a particularly harsh winter. State one reason why a harsh winter would have this negative effect on the bison population. *
People who live in rural areas often use septic tanks for the storage of sewage. These people often flush a product containing harmless bacteria down the toilet once a month. These bacteria break down the sewage before it enters the environment. State one ecologically sound reason for this action. *
Base your answer to question 66-68 on the information below and on your knowledge of biology.
Officials OK Insect Release To Control Invasive Vine
The U.S. federal government has approved the release of a non-indigenous [nonnative] insect on Guam and in the Northern Marianas to control the rapid spread of a vine that is covering forests like a blanket, the Saipan Tribune reports.
The U.S. Department of Agriculture has given the green light to breed and release the Heteropsylla spinulosa insect, which eats the Mimosa dilotricha [diplotricha] vine. The fast- spreading plant is found in many Pacific Islands, but is particularly widespread in the Northern Marianas and on Guam. It usually kills the trees and shrubs that it covers.
Officials will collect the insect from Pohnpei, in the Federated States of Micronesia, Palau and Australia.
Source: “Officials OK Insect Release To Control Invasive Vine,” 4/2/08,
Discuss the advantages of using the insect to control the rapid spread of the Mimosa diplotricha vine on Guam and the Northern Marianas. In your answer, be sure to:
• state one possible way the Mimosa diplotricha vine kills trees and shrubs 
• identify one location from which the Heteropsylla spinulosa insect will be collected 
• explain why releasing the insect might be safer than spraying chemicals to kill the vine 
Base your answer to question 69-72 on the information below and on your knowledge of biology.
Chickens as Drug Factories
Scientists in Scotland have successfully produced five generations of chickens that lay eggs containing certain protein-based drugs. The scientists changed the DNA of the chickens so that two drugs, one used to treat skin cancer and the other used to treat multiple sclerosis, were present in the egg whites. Cows, sheep, and goats have already been altered to produce protein-based drugs in their milk. Chickens are considered good “drug factories” because they are inexpensive to care for, they grow fast, and their chicks inherit the special drug-producing ability.
Explain why scientists altered the DNA of the chickens instead of altering a protein already present in the chickens. In your answer, be sure to:
• identify the technique used to alter the DNA 
• state one reason why the scientists altered the DNA of the chickens instead of altering a protein already present in the chickens 
• state one advantage of using chickens for this procedure 
• state one reason why some people might not support this method of drug production *
Certain chemicals, such as cytochrome C, are found within cells of all living organisms. The biochemical structure of cytochrome C in ground finches and in tree finches is very similar. This suggests that tree finches and ground finches have*
The diagram below represents the results of a laboratory procedure.
This procedure is used to*
Base your answers to questions 75 through 77 on the diagram below and on your knowledge of biology.
Which species of finch has an edge-crushing bill that can also probe into plants for food?*
One finch that would most likely compete with the warbler finch for food is the*
The large ground finch, sharp-billed ground finch, and small tree finch inhabit the same island. If the insect population decreases, which finch would most likely be affected? Support your answer. 
Base your answers to questions 78 and 79 on the information below and on your knowledge of biology.
An artificial cell filled with a glucose solution was placed in a beaker of water, as represented below. The beaker was left undisturbed for 20 minutes.
In the diagram below, draw in the expected location of the glucose molecules after 20 minutes. 
If both glucose and starch were added to the artificial cell, where would the starch be located after 20 minutes? 
State one advantage of using a stain to study frog skin cells with a microscope. *
An experiment was designed to test whether students could squeeze a clothespin more times in 1 minute after resting or after exercising. What would be a hypothesis for the experiment?*
DNA samples can be separated according to size using the technique of*
Base your answers to questions 83 through 85 on the Universal Genetic Code Chart below and on your knowledge of biology.
Complete the missing amino acid sequences for plant species A in the table below. *
Complete the missing mRNA base sequences for plant species B in the table below. 
Based on the information provided in the completed table, which plant species is most closely related to the endangered species? Support your answer.