Unit 1-target 7-scientific Method Quiz

During an experiment, this should be done so that there is evidence to support or reject the hypothesis.

A hypothesis is

• A definite answer to a given problem.

• A testable possible explanation of an observation.

• A proven statement.

• A concluding statement.

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?

• Discard those results and repeat the experiment.

• Accept the hypothesis and exclude data that does not fit.

• Reject the hypothesis and assume it is incorrect.

• Create a new hypothesis and a new experiment to test it.

A scientist noticed that in acidic pond water some salamanders developed with curved spines. This was a(n)

• Hypothesis.

• Theory.

• Observation.

• Control.

Typically, the order in which the steps of the scientific method are applied is

• Data collection, observations, hypothesis, controlled testing, verification, theory.

• Observations, hypothesis, controlled testing, data collection, verification, theory.

• Observations, hypothesis, controlled testing, theory, data collection, verification.

• Observations, hypothesis, data collection, controlled testing, verification, theory.

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?

• Accept the results; one trial is all that is necessary to test a hypothesis.

• Accept the results; the results of this experiment support their hypothesis.

• Perform more trials using a different type of meat, under the same conditions as the first experiment.

• Perform more trials using the same type of meat, under the same conditions as the first experiment.

Dr. Graham has written a paper on the internal temperature of nests of alligator eggs. His data shows that temperature determines the sex of the hatchlings. What is the best method of validating the reliability of Dr. Graham’s experiment?

• Dr. Graham should clearly document the experimental process.

• Dr. Graham should repeat the experiment at another time of year.

• Several scientists should repeat the experiment using Dr. Graham’s design.

• Several scientists should observe Dr. Graham as he repeats the experiment.

Which example of scientific methodology is incorrect?

• Observation—a number of people in a certain place dying of a disease outbreak

• Measurement—a record of the number of people with symptoms of a disease and the number of people who had died from the disease

• Analysis of data—comparison of the effects of mixing monkey cells with virus-containing blood in test tubes and the effects of mixing liquid from these test tubes with fresh monkey cells

• Inference making—identification of the Ebola virus as the cause of a disease by taking electron micrographs of substances found in the blood of persons affected with the disease

A hypothesis that does not explain an observation

• Is known as an inaccurate forecast.

• Often predicts a different observation.

• Is rejected.

• None of the above

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?

• Change the focus of the research from moisture to light sensitivity.

• Assume these findings are representative of all pill bugs and accept the null hypothesis.

• Find other organisms at the site to test for changes in moisture level.

• Look for more pill bugs at the site to generate a larger sample size.

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?

• 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

• 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

• Placing 5 grams of sugar in 10 pots, and no sugar in the other 10 pots; then giving all 20 pots 40 mL of water daily.

• 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

This is necessary so that other scientists can confirm the validity of the results of an experiment.