NOS

B

A biologist conducted an experiment to determine whether the survival of tadpoles was affected by the pH of the pond water in which they live. His results were that 20% of tadpoles survived at a pH of 5.5, 40% at 6.0, 85% at 6.5, 75% at 7.0, 65% at 7.5, and 45% at 8.0. Based on this information, the difference between the percentage of surviving tadpoles is greatest for which 2 consecutive pH values? A. 5.5 and 6.0 B. 6.0 and 6.5 C. 6.5 and 7.0 D. 7.5 and 8.0

D

A biologist recorded the number of rabbits in a population over 30 generations. Point A is the 10 generation of about 500 and Point B is generation 15 with about 200 Which of the following statements best explains why the number of rabbits in the population dramatically decreased between Points A and B? Shortly after the 10th generation: A. A new predator that feeds solely on the rabbits' main competitor was introduced into the rabbits' habitat B. Area farmers set traps for coyotes, the rabbits' main predator C. A change in environmental conditions led to a significant increase in the amount of food available to the rabbits. D. A fatal disease infected a large proportion of the rabbits in this population

A

A biologist surveys 10 bald eagle nests in Illinois and 10 bald eagle nests in Iowa. He counts the number of eggs in each nest and then records the number of fledged young. His data is provided. Nest ID (State-Nest #) then number of eggs, and then number of fledged young. IL-1, 1, 1 IL-2, 3, 2 IL-3, 2, 2 IL-4, 2, 2 IL-5, 1, 1 IL-6, 2, 1 IL-7, 1, 1 IL-8, 2, 2 IL-9, 3, 3 IL-10, 2, 2 IA-1, 2, 2 IA-2, 2, 2 IA-3, 3, 2 IA-4, 3, 3 IA-5, 2, 2 IA-6, 3, 3 IA-7, 1, 0 IA-8, 1, 1 IA-9, 2, 2 IA-10, 3, 2 Which of the following types of graphs would you use to best compare the average number of eggs per nest in Illinois and Iowa A. Bar graph B. Line graph C. Pie chart D. Scatter plot

B

A hypothesis is... A. Same as a theory B. A proposed explanation for a set of observations C. A widely excepted idea D. An explanation of an idea that is supported by a large body of evidence

C

A microbiologist wants to determine whether a certain chemical affects the growth rate of bacteria. Which method would be most efficient and reliable for tracking the bacteria population's growth rate each hr for 24 hrs? A. Counting individual bacterial cells B. Determining the mass of the tube containing the bacteria C. Measuring the light absorbance of the populations in the tubes using a spectrophotometer D.Calculating the size of the population using the average doubling time of the bacteria in the absence of the chemical

A

A scientific theory is based on experimental results that satisfy which criterion? A. They can be replicated by others. B. Their significance is supported by experts. C. They are absolute and cannot be challenged. D. They are inconsistent with personal experience.

D

A scientist found that the results of an experiment did not support her hypothesis. If she is following proper scientific procedure, what should she do next? A. Discard those results and repeat the experiment B. Accept the hypothesis and exclude data that does not fir C. Reject the hypothesis and assume it is incorrect D. Create a new hypothesis and a new experiment to test it

D

A student doing research on pill bugs hypothesized that pill bugs would be found in moist habitats, but not in dry habitats. The student found 2 pill bugs at 1 site: 1 under a log in moist conditions and another underneath some dry leaves. This finding did not support the student's original hypothesis. What should the student do next to determine if the original hypothesis is valid? A. Change the focus of the research from moisture to light sensitivity B. Assume these findings are representative of all pill bugs and accept the null hypothesis C. Find other organisms at the site to test for changes in moisture level D. Look for more pill bugs at the site to generate a larger sample size

D

A theory A. Is a proven idea B. An early concept C. Description of a belief that invokes the supernatural D. An explanation of an idea that is broad in scope and supported by a large body of evidence

A

Aden wanted to determine the effects of stress on heart rate. As his stress factor, he asked subjects to complete math problems. He randomly divided his biology class of 24 students into 2 groups. He gave 1 group a timed test of difficult algebra problems; he gave the other group a timed test of simple arithmetic problems. Aden measured heart rates both before and immediately after the test. He hypothesized that the group given the difficult problems would show a higher mean heart rate (that is, a higher stress level) than those given simple problems. Results were difficult algebra 72 bpm as an initial heart rate and 77 as a final heart rate and the simple arithmetic was 71 bpm as an initial heart rate and 75 as a final heart rate. Because the results were so similar, Aden decided to do a second test in which he collected additional types of information. Which changes in experimental design would best help him accept or reject his initial hypothesis? A.Heart rates of the 2 groups taken during the test B.Average math grades of the 2 groups C.Before and after heart rates when both groups are given a more difficult test D.Before and after heart rates when a single group is given the same test

D

After questions were raised about his research, Dr. H., a university scientists, admitted he fabricated much of the data in a paper. Which procedure was probably LEAST effective in discovering and documenting this case of scientific dishonesty? A. Peer review of Dr. H.'s paper before its publication B. Comparison of Dr. H.'s research results with related research results of other scientists C. Inability of other scientists to replicate Dr. H.'s results D. Complaints of Dr. H.'s secrecy regarding his research techniques

D

Aisha wants to conduct an experiment to determine whether sun and shade varieties of the same plant species prefer the same wavelengths of light. She plans to measure rates of photosynthesis. Which design would be best for her experiment? A.1 plant of the sun variety tested under blue light only, and 1 plant of the shade variety tested under blue light only. B.4 plants of the sun variety: 1 tested under blue light, 1 under green, 1 under red, and 1 under yellow light, and 4 plants of the shade variety:1 tested under blue light, 1 under green, 1 under red, and 1 under yellow light C.10 plants of the sun variety tested under blue light only; and 10 plants of the shade variety tested under blue light only D.40 plants of the sun variety: 10 tested under blue light, 10 under green, 10 under red, and 10 under yellow light, and 40 plants of the shade variety: 10 tested under blue light, 10 under green, 10 under red, and 10 under yellow light.

D

Before Gregor Mendel's experiments with pea plants, many scientists believed that offspring inherited a blend of parental traits. Mendel's results contradicted this theory. What aspect of the nature and philosophy of science does this change in thinking exemplify? A. Prior knowledge affects scientific observation B. Scientific knowledge is more often wrong than right C. Scientists guess when formulating scientific theories D. Scientific knowledge changes as new data becomes available.

D

Biology students carried out an experiment to determine if a certain fertilizer increased the height of plants. The students selected 4 types of plants and planted 10 seeds of each type. Five seeds of each type were treated with fertilizer and 5 seeds of each type were not treated with fertilizer. All other conditions were identical. The students recorded the plant height after 120 days. The castor bean - plants with fertilizer -150 cm, 145 cm, 155 cm, 160 cm, and 140 cm and plants without fertilizer - 145 cm, 140 cm, 150 cm, 155 cm, and 140 cm. The okra - plants with fertilizer - 75 cm, 80 cm, 75 cm, 75 cm, and 75 cm and plants without fertilizer - 70 cm, 80 cm, 70 cm, 65 cm, 70 cm. The radish - plants with fertilizer - 15 cm, 20 cm, 25 cm, 20 cm, and 20 cm, and plants without fertilizer - 10 cm, 15 cm, 20 cm, 15 cm, 20 cm. The tomato - with fertilizer - 150 cm, 145 cm, 155 cm, 160 cm, 165 cm, and plants without fertilizer - 140 cm, 130 cm, 135 cm, 120 cm, and 125 cm. Based on the results shown in this table, the difference (in cm) between the average height of the plants treated with fertilizer and the average height of the unfertilized plants was greatest for which of these plant types? A. Castor bean B. Okra C. Radish D. Tomato

C

Bryce is planning to plant tomatoes in his garden. He wants to determine if tomato seeds will germinate (sprout) faster in soil with sugar added than in soil with no sugar added. He plants one seed in 100 grams of soil in each of 20 pots. Which experiment will give him the most useful results? A. Placing 5 grams of sugar in all 20 pots; then giving 10 pots 40 mL of water daily and the other 10 pots 80 mL of water daily B. Placing 5 grams of sugar in 10 pots, and 10 grams of sugar in the other 10 pots; then giving all 20 pots 40 mL of water daily C. Placing 5 grams of sugar in 10 pots and no sugar in the other 10 pots; then giving all pots 40 mL of water daily D. Placing 5 grams of sugar in 10 pots, and no sugar in the other 10 pots; then giving the 10 pots with sugar 40 mL of water daily and the 10 pots without sugar 80 mL of water daily

C

Dr. Graham has written a paper on the internal temperature of nests of alligator eggs. His data show that temperature determines the sex of the hatchlings. What is the best method of validating the reliability of Dr. Graham's experiment? A. Dr. Graham should clearly document the experimental process B. Dr. Graham should repeat the experiment at another time of year C. Several scientists should repeat the experiment using Dr. Graham's design D. Several scientists should observe Dr. Graham as he repeats the experiment.

A

Dr. Hansen performs an experiment testing the effectiveness of different cough syrups. Identify the independent variable in the experiment. A. Type of cough syrup B. Flavor of the cough syrup C. Number of people taking each cough syrup D. Number of day people take each cough syrup.

D

Ebola virus is a potentially deadly virus in the blood which causes Ebola fever. Ebola virus if often spread by monkeys. Scientists used 2 groups of monkey kidney cells in an experiment to confirm the first human case of Ebola fever. The scientists inoculated cells in Group 1 with samples of the Ebola virus taken from a human with Ebola fever. They did not inoculate the cells in Group 2. What was the control group in the experiment? A. The Ebola virus B. All of the monkey kidney cells C. Monkey kidney cells in Group 1 D. Monkey kidney cells in Group 2

A

Ella told her sister the sun would set at 6:30 p.m. and there would be a full moon on Thursday night. Under which basic assumption of science is she operating? A. Nature is orderly B. Knowledge is superior to ignorance C. Nothing is self-evident D. All phenomena have natural causes

D

Ethan wants to determine whether temperature affects the rate at which mold grows on bread. He puts one piece of bread inside a petri dish, closes the lid, and places the petri dish in the refrigerator. To determine whether temperature affects the growth of mold, Ethan should place another piece of bread into a petri dish: A. leave the dish uncovered, and place the dish in the refrigerator B. cover the dish, and place the dish in the refrigerator C. leave the dish uncovered, and place the dish in a dark, room temperature cabinet D. cover the dish, and place the dish in a dark, room temperature cabinet

B

If a researcher makes an experimental observation that is contrary to well-established scientific understanding, what should the next step be? A. Ignoring the results of the experiment if they support the hypothesis B. Re-evaluating the procedure and replicating the experiment C. Publishing the research in a well-known journal D. Manipulating the data so it conforms to current understanding

D

In an experiment to study the digestion of casein (a protein found in milk), students prepared 5 test tubes containing a casein suspension. The students recorded the contents and treatment of each test tube in this table. Pancreatin contains a mixture of enzymes in aqueous suspension. Each tube appeared clear during the entire process until calcium chloride (CaCltwo) was added, at which time some cloudy. Tube 1 had a Casein suspension of 1.0 mL and Pancreatin of 1.0 mL and incubated at 20 degrees, Tube 2 had a Casein suspension of 1.0 and Pancreatin of 1.0 and incubated at 37 degrees, Tube 3 repeated number 2 (from what we can see on the worksheet), Tube 4 had a Casein suspension of 1.0 and Pancreatin of 0.0 and a temperature of 20 degrees, and Tube 5 had a Casein suspension of 0.0 and Pancreatin 0.0 and temperature of 20 degrees. How should the students modify their procedure to make Tube 4 the best control for Tube 1? A. By incubating Tube 4 at 37 degrees (C) instead of 20 degrees B. By incubating Tube 4 for 2 minutes instead of 10 minutes C. By adding 1.0 mL of pancreatin to Tube 4 for a total volume of 2.0 mL D. By adding 1.0 mL of distilled water to Tube 4 for a total volume of 2.0 mL

A

In an experiment to study the digestion of casein (a protein found in milk), students prepared 5 test tubes containing a casein suspension. The students recorded the contents and treatment of each test tube in this table. Pancreatin contains a mixture of enzymes in aqueous suspension. Each tube appeared clear during the entire process until calcium chloride (CaCltwo) was added, at which time some cloudy. Tube 1 had a Casein suspension of 1.0 mL and Pancreatin of 1.0 mL and incubated at 20 degrees, Tube 2 had a Casein suspension of 1.0 and Pancreatin of 1.0 and incubated at 37 degrees, Tube 3 repeated number 2 (from what we can see on the worksheet), Tube 4 had a Casein suspension of 1.0 and Pancreatin of 0.0 and a temperature of 20 degrees, and Tube 5 had a Casein suspension of 0.0 and Pancreatin 0.0 and temperature of 20 degrees. To determine the effect of temperature on the rate of protein digestion, which tubes should the students compare? A. Tubes 1 and 2 B. Tubes 1 and 3 C. Tubes 2 and 3 D. Tubes 2 and 4

C

In an experiment to study the digestion of casein (a protein found in milk), students prepared 5 test tubes containing a casein suspension. The students recorded the contents and treatment of each test tube in this table. Pancreatin contains a mixture of enzymes in aqueous suspension. Each tube appeared clear during the entire process until calcium chloride (CaCltwo) was added, at which time some cloudy. Tube 1 had a Casein suspension of 1.0 mL and Pancreatin of 1.0 mL and incubated at 20 degrees, Tube 2 had a Casein suspension of 1.0 and Pancreatin of 1.0 and incubated at 37 degrees, Tube 3 repeated number 2 (from what we can see on the worksheet), Tube 4 had a Casein suspension of 1.0 and Pancreatin of 0.0 and a temperature of 20 degrees, and Tube 5 had a Casein suspension of 0.0 and Pancreatin 0.0 and temperature of 20 degrees. Which question can the students answer by comparing the results of Tubes 2 and 3? A. What effect does incubation temperature have on the rate of protein digestion? B. What effect do incubation temperature and time have on the total quantity of protein digested? C. How does incubation time influence the relative amount of protein digested? D. How does the addition of an enzyme influence the rate of protein digestion?

B

In an experiment, 6,000 people with a common cold who drank orange juice daily had symptoms that lasted an average of 4 days. Another 6,000 people with a common cold who did not drink orange juice daily had symptoms that lasted an average of 7 days. Scientists repeated the experiment 3 times with the same results. They concluded that orange juice reduces the length of the common cold. Was this conclusion valid, and why? A. Yes, because vitamin C is a known common cold cure B. Yes, because scientists repeated the experiment C. No, because the sample size was too small D. No, because some of the people who drank orange juice did not feel better

B

Jaime plans to use a variety of sources in writing his term paper on global warming. Which source would likely contain the most unbiased scientific information? A. A website sponsored by an environmental organization B. A research paper in the peer-reviewed journal Climatology C. A Scientific American article written by a journalist D. A telephone interview with an energy company representative

D

Lupe performed an experiment to test the ability of different heavy metals to inhibit normal enzyme activity in liver. Lupe placed 5g of liver in each of 5 test tubes. In 4 of the tubes, she also placed equal amounts of a heavy metal. She then added 6mL of hydrogen peroxide to all 5 tubes. She used the resulting bubble column as an indicator of enzyme activity in the liver and recorded the data. (Note: The greater the height of the bubble column, the greater the enzyme activity.) Control (No heavy metal) - Trial#1 - 7, Trial#2 - 8, Trial#3 - 8, Average - 7.7 Lead (Pb) - Trial#1 - 4, Trial#2 - 4, Trial#3 - 5, Average - 4.3 Mercury (Hg) - Trial#1 - 4, Trial#2 - 6, Trial#3 -5, Average - 5.0 Magnesium (Mg) - Trial#1 - 5, Trial#2 - 5, Trial#3 - 6, Average - 5.3 Zinc (Zn) - Trial#1 - 10, Trial#2 - 9, Trial#3 - 3, Average - 9.3 Based on Lupe's data, enzyme activity was inhibited the most by which of the 4 heavy metals? A. Zn B. Mg C. Hg D. Pb

B

Lydia works in a flower shop after school. She notices that the hydrangeas in Container 1 have pink blossoms, while the hydrangeas in Container 2 have blue blossoms. She make sure they all receive the same amount of light and water. Her boss tells her that the flowers were all grown from the same seed variety. Lydia discovers, after testing the soil, that although the same type of soil was used, the soil in Container 1 has a pH of 6.0, and the soil in Container 2 has a pH of 5.0. As described in the scenario above which fundamental assumption of science did Lydia put into practice while working at the flower shop? A. We arrive at knowledge mainly by using our sense of intuition B. We learn how the natural world works by observing it and by conducting experiments. C. We can develop a theory based on a few consistent experimental results. D. We can manipulate several variables at a time in a controlled experiment

A

Lydia works in a flower shop after school. She notices that the hydrangeas in Container 1 have pink blossoms, while the hydrangeas in Container 2 have blue blossoms. She makes sure they all receive the same amount of light and water. Her boss tells her that the flowers were all grown from the same seed variety. Lydia discovers, after testing the soil, that although the same type of soil was used, the soil in Container 1 has a pH of 6.0, and the soil in Container 2 has a pH of 5.0. Lydia most likely conducted her investigation to answer what question about hydrangeas? A.How does the chemistry of the soil affect the color hydrangea blossoms? B.What role do genetic factors play in hydrangea color? C.Do varying degrees of light affect hydrangea color? D.What type of soil will produce a hydrangea with both pink and blue blossoms?

D

Many insects produce pheromones (chemical signals) to facilitate mating and reproduction. Scientists have discovered that pheromones, if given at a certain time in an insect's life cycle, can confuse male insects and disrupt the mating process. Crop growers want to use this knowledge to help control insect pests. Which step would be LEAST likely to change this scientific information into a usable technology? A. Determining which pheromones most disrupt the mating of common insect pests B. Determining when, during an insect pest's life cycle, the application of pheromones would most disrupt mating C. Developing a practical means of dispersing the pheromones D. Developing stronger insecticides to kill insects not affected by the pheromones

A

Ming volunteers for a study to determine whether a certain medication helps people sleep. Volunteers are assigned to 1 of 2 groups. Volunteers in Group 1 are given the medication, and volunteers in Group 2 are given a placebo. Which of the following steps is necessary to ensure the scientific validity of the results? A. Assigning the subjects to each group at random B. Assigning all of the subjects with sleeping problems to the placebo group C. Telling subjects if they are receiving the medicine or the placebo D. Placing 100 volunteers in Group 1 and 10 volunteers in Group 2

A

Morgan hypothesizes that the activity of amylase, an enzyme that catalyses the breakdown of starch, will be greater at 37 degrees C than at 25 degrees C. She prepares 2 tubes: Tube 1 and Tube 2. Morgan adds 2g of starch and 1mL of an enzyme suspension to Tube 1 and incubates it at 37 degrees C for 20 min. To accurately test her hypothesis, Morgan should add 2g of the starch and 1mL of the enzyme suspension to Tube 2 and incubate it at _____ for _______. A. 25 degrees C; 20 minutes B. 37 degrees C; 20 minutes C. 25 degrees C; 10 minutes D. 37 degrees C; 10 minutes

B

Mrs. Lewis set up a lab for her biology students using a culture of the small crustacean Daphnia, obtained from a pond that was 20 degrees C. The students are to investigate the effect temperature has on Daphnia. The students will observe the crustacean's heartbeat under the microscope, at different temperatures, and count the number of heartbeats per sec. If the experiment is designed correctly, what will the students choose for the experimental treatment? A. Placing 5 identical cultures of Daphnia at 20 degrees C B. Placing each of 5 identical cultures of Daphnia at a different temperature C. Placing 5 cultures, each with a different type of crustacean, at 20 degrees C D. Placing 5 cultures, each with a different type of crustacean, at a different temperature

A

Mrs. Lewis set up a lab for her biology students using a culture of the small crustacean Daphnia, obtained from a pond that was 20 degrees C. The students are to investigate the effect temperature has on Daphnia. The students will observe the crustacean's heartbeat under the microscope, at different temperatures, and count the number of heartbeats per sec. What is the independent variable in this experiment? A.Temperature of the samples B.Number of heartbeats/sec C.Number of Daphnia in the cultures D.Type of microscope used

D

Paul and Simon want to determine who is more git. They decide to run in place for 5 minutes and then measure their blood pressures to see whose returns to normal most quickly. They record the data. For Paul, his sitting Systole/Diastole (mm Hg) is 114/73 and his pulse (beats/min) is 58, exercising Systole/Diastole is 150/75 and his pulse is 94, 1 minute after exercising is 142/72 and the pulse is 74, 3 minutes after exercising is 122/72 and the pulse is 65, and 5 minutes after exercising his Systole/Diastole is 114/73 and his pulse is 58. For Simon, his sitting Systole/Diastole is 113/74 and his pulse is 62, exercising, it is 170/75 and pulse is 100, 1 minute after exercising 158/73 and pulse is 76, 3 minutes after exercising 139/73 and pulse is 70, and 5 minutes after exercising his Systole/Diastole is 121/74 and pulse is 66. Paul told Simon that the heart pumps more blood during exercise than at rest. How do the experiment's results support Paul's statement? A. Exercise increases only the pulses. B. Exercise increases only the systolic pressure. C. Exercise increases both the systolic and diastolic pressure. D. Exercise increases both pulse and the systolic pressure.

C

Scientific experimentation can most likely answer which question regarding a bird population? A. How does a baby bird learn to recognize the type of food it can eat? B. How does the type of food a bird eats affect the number of offspring it produces? C. What is the relationship between beak size and the number of offspring a bird produces? D. Why does a bird with a very short beak produce more offspring than a bird with a very long beak?

D

Scientists collected data on the height and weight of individuals in a population. They recorded their results in the scatterplot in the 1st worksheet (no 26). What is the most accurate conclusion regarding the relationship between height and weight? A. Tall individuals are always heavier than short individuals. B. There is no relationship between height and weight. C. There is a negative relationship between height and weight. D. There is a positive relationship between height and weight.

C

Several students in a biology lab tested mealworms' preference for damp or dry conditions. The students placed 50 mealworms one-by-one in the middle of a layer of paper towels with a damp area and a dry area. The mealworms were allowed to move freely over the paper towels for 10 min. After 10 min the students noted the location of each mealworm. The data is summarized below. 47 Damp and 3 Dry In a second experiment the same 50 mealworms were exposed to each of 4 different arrangements of paper towels with food sources in different locations. Food sources just off the paper towels can be sensed by the mealworms, but are out of their reach. The diagram below shows the location of the worms after 10 min. Food source on the side of the damp side - 45 on the damp side and 5 on the dry side Food source on the side of the dry side and in the middle of the damp side - 49 damp side and 1 dry side Food source on the side of the damp side and in the middle of the dry side - 2 damp side and 48 dry side Food source in the middle of both damp and dry sides - 24 damp and 26 dry Which conclusion best supports the data collected in both experiments? A. Mealworms prefer damp conditions over dry conditions. B. Mealworms prefer dry conditions over damp conditions C. Mealworms are more strongly influenced by food than by damp or dry conditions D. Mealworms are more strongly influenced by damp or dry conditions than by food

C

Sunee and Jamila grow 2 distinct strains of E. coli bacteria following appropriate lab procedures. In Experiment 1, they use a new culture of Strain X and a 30-day old culture of Strain Y. In Experiment 2, they use a new culture of Strain Y and a 30-day old culture of Strain X. Sunee and Jamila measure the nuber of bacterial colonies and record the data. Experiment 1 - new Strain X - goes down daily (then goes up slightly at day 20) 30-day-old Strain Y - goes up daily (then slightly down at 20) Experiment 2 - 30-day-old Strain X - goes up daily (then down slightly at 20) new Strain Y - goes down daily What is the most accurate conclusion about the growth rate of the bacteria? A. Strain X grows faster than Strain Y regardless of the culture's age. B. Strain Y grows faster than Strain X regardless of the culture's age C. The 30-day old culture grows faster regardless of the strain D. The new culture grows faster regardless of the strain.

A

The DNA of a genetically modified (GM) plant contains genes from other species. Some environmentalists claim that GM plants may pose environmental problems. Which occurrence involving a GM plant will most likely cause an environmental problem? A. Herbicide-resistant genes transfer to weeds when weeds hybridize with a GM plant B. An insect-resistant GM plant produces 20% more grain than the same non-GM variety of the plant C. A disease-resistant GM plant that cannot reproduce is transported into surrounding fields D. A GM plant is resistant to its most threatening pest, but is not resistant to less threatening pests.

C

The number and type of macroinvertbrates are good indicators of the amount of pollution in a stream because they tolerate varying levels of pollution. A biology textbook provides this of tolerance levels. Stonefly - Low Crayfish - Medium Blackfly - High Leech - Very High Biology students gather samples from a local stream and conclude that it is extremely polluted. Which most likely reflects the data gathered by the students? A. Stonefly - 2 Crayfish - 10 Blackfly - 5 Leech - 3 B. Stonefly - 2 Crayfish - 1 Blackfly - 3 Leech - 2 C. Stonefly - 0 Crayfish - 2 Blackfly - 5 Leech - 5 D. Stonefly - 0 Crayfish - 12 Blackfly - 8 Leech - 3

B

The roll of a control in an experiment A. Prove a hypothesis is correct B. Proved a basis of comparison to the experimental group C. Insure comparability

C

There was a growth curve for Paramecium grown in a 1.0 L flask containing pond water at 20 degrees C. The pond water is continually filtered to remove waste products, and nutrients are added at a constant rate. How could the experiment be modified to determine whether temperature influences the population size of Paramecium? A. Repeat the procedures described using 1 flask, and increase the temperature to 25 degrees C for Days 10-15 B. Repeat the procedures described using 1 flask, and vary the temperature randomly during the entire incubation time C. Repeat the procedures described using 2 flasks; incubate 1 flask at 15 degrees C and the other at 25 degrees C D. Repeat the procedures described using 2 flasks, incubate both flasks at 20 degrees C.

C

These graphs on the first worksheet (no 27) represent Earth's estimated carbon dioxide (CO2) levels and temperature over the past 400,000 years. Using the data in the graphs determine the relationship between Earth's CO2 levels and temperature. A. The temperature falls as the CO2 level rises. B. The CO2 level and the temperature are equal. C. There is a positive correlation between CO2 levels and temperature. D. There is a negative correlation between CO2 levels and temperature.

D

Two students conducted studies to determine the amount of bacteria in hamburgers cooked to different internal temperatures. The students cooked 3 hamburgers: 1 rare, 1 medium, and 1 well-done. The students then took a core from the center of each hamburger and placed each core in a separate petri dish with nutrient agar. Each dish was incubated until colonies formed. The students hypothesized that the rare hamburger core would generate the most bacteria colonies. Eight hundred colonies grew in the dish containing the rare hamburger core, 400 colonies grew in the dish containing the medium hamburger core, and 0 colonies grew in the dish containing the well-done hamburger core. What is the most appropriate next step for the students to take in this study? A. Accept the results; one trial is all that is necessary to test a hypothesis. B. Accept the results; the results of this experiment support their hypothesis. C. Perform more trials using a different type of meat, under the same conditions as the first experiment. D. Perform more trials using the same type of meat, under the same conditions as the first experiment.

B

Two students wanted to estimate and compare the density of 2 species of plants in a grassland habitat. Student 1 randomly located 10 sampling plots and counted the number of plants of each species in each sampling plot. Each sampling plot was 1 m squared. The number of individuals of each species that Student 1 counted in each sampling plot were: Species A: 9, 8, 15, 21, 8, 4, 25, 1, 11, 0 Species B: 15, 14, 15, 16, 15, 17, 14, 15, 18, 16 Student 2 was in a hurry and decided to locate his 10 sampling plots in the areas with the least amount of vegetation. He counted the number of plants of each species in each 1 m squared sampling plot. The number of individuals of each species that Student 2 counted in each sampling plot were: Species A: 2, 4, 1, 0, 0, 4, 2, 1, 1, 0 Species B: 13, 15, 14, 15, 14, 14, 15, 15, 14, 14 Based on the data provided by Student 1, how would you best describe the spatial distribution of Species B relative to Species A? A. Species A appears to be more evenly distributed than Species B. B. Species B appears to be more evenly distributed than Species A. C. Both Species A and Species B appear to be distributed evenly. D. Neither Species A or Species B appear to be distributed evenly.

A

What is the best definition of a scientific theory? A. An explanation of how and why a natural phenomenon behaves the way it does B. A description of an invariable relationship that exists in nature C. A speculation or guess about how nature works D. An unproven fact

C

What is the goal of basic scientific research in biology? A. Finding cures that will prolong human life through the study of disease B. Providing a better understanding of the origin of life in the universe C. Developing a more complete understanding of the interactions within and surrounding living organisms D. Creating a comprehensive set of laws that allow us to predict how matter behaves and interacts

B

Which experimental design would provide scientists with the best data for investigating which type of feed yields the greatest gain in lean muscle mass in cattle? A. Test 5 different types of cows with the same feed mixture and measure their weight gain at the end of a 6-week trial. B. Test 5 similar groups of cows with 5 different feed mixtures and measure their weight gain at the end of a 6-week trial. C. Test 5 similar groups of cows with the same feed mixture, give each group varying amounts of feed, and measure their weight gain at the end of a 6-week trial D. Test 5 different types of cows with 5 different feed mixtures, give each group varying amounts of feed, and measure their weight gain at the ends of a 6-week trial

C

You notice that over the past month many students on campus have started wearing a new style sweatshirt. You think to yourself that perhaps the bookstore has recently started selling this new sweatshirt style. This prediction is an example of ? A. Type of experimental question B. Type of observation C. Type of hypothesis D. Type of experiment