Sc N 1 2

SC.7.N.1.2

Scientists frequently repeat the experiments of others scientists. Why is this important in science?

a. Scientists often ask each other for help in performing experiments.

b. Replication of experiments helps to confirm and verify results.

c. Scientists frequently perform other scientists’ experiments in order to practice their technique.

d. Repeating experiments is an effective way to make sure a laboratory is in optimal condition.

• a

• b

• c

• d

SC.7.N.1.2

Cara read an article on why repetition and replication are so important, but she did not understand the difference between them. Which of the following best explains the two terms?

a. Repetition is when a scientist repeats an experiment; replication is when a scientist conducts an experiment on genetic material.

b. Repetition is when a scientist does the same experiment a number of times; replication is when other scientists reproduce a scientist’s experiment.

c. Repetition is when a scientist publishes in more than one scientific periodical; replication is when another scientist reproduces another scientist’s results.

d. Repetition is when a scientist commits an error in an experiment the first time and must repeat it; replication is when a scientist repeats an experiment to make sure it is valid.

• a

• b

• c

• d

SC.7.N.1.4

Jason states the following prediction: “As the air temperature increases, the air in a balloon will expand, increasing the circumference of the balloon.”

Some of Jason’s observations during his experiment are shown below. Which of the following is the outcome variable (dependent variable) for an experiment designed to test Jason’s prediction?

a. circumference of the balloon

b. material the balloon is made of

c. length of the balloon’s string

d. air temperature

• a

• b

• c

• d

Tags

NGSS.MS-PS1-4

SC.7.N.1.4

Kaylee reads an article that states that the frequency of chirping by crickets is related to the temperature of their environment. She wants to conduct an experiment to see if this is true. Kaylee states this hypothesis: Crickets chirp more frequently when the temperature of their environment increases. What is the test variable (independent variable) and outcome variable (dependent variable) in Kaylee’s experiment?

a. test variable (independent variable): number of crickets; outcome variable (dependent variable): frequency of chirping

b. test variable (independent variable): temperature of environment; outcome variable (dependent variable): frequency of chirping

c. test variable (independent variable): number of crickets; outcome variable (dependent variable): temperature of environment

d.test variable (independent variable): frequency of chirping; outcome variable (dependent variable): temperature of environment

• a

• b

• c

• d

SC.6.N.1.2

Experiments are often repeated many times by the same or different scientists. What is the most important reason more than one scientist should conduct an investigation using the same methods?

a. If the results are the same, replication of the investigation helps to confirm the results.

b. The competition makes the scientists work more carefully.

c. More than one scientist is interested in the problem.

d. Different scientists might perform the experiment differently.

• a

• b

• c

• d

SC.6.N.1.4

Ty and Crystal are working together to learn about surface tension. They each add pennies to their own cup of water to see how many they can add before the cup overflows. Ty is able to add 15 pennies. Crystal is able to add 38. What should their next step be?

a. They should discuss differences in their methods.

b. They should each claim that their answer is right.

c. They should record their results and move on to a different investigation.

d. They should repeat the experiment using different pennies.

• a

• b

• c

• d

SC.6.N.1.4

Miguel and Blanca are each using a questionnaire with different groups of students to determine which flavor of juice is preferred. After administering their questionnaire, they compare their results and find that they are very different. How should Miguel and Blanca proceed?

a. They should throw out their results and start over.

b. They should decide which set of results is better and throw out the other set.

c. They should compare their methods to see if they can explain why their results varied.

d. One of the students should change their results so the two sets of results match up better.

• a

• b

• c

• d