Nature Of Science

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

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

• Replication of experiments helps to confirm and verify results.

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

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

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?

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

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

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

• 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.

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

The variable that is being measured or observed is called the _______________. Hint: this is the variable that is the result or effect

• independent variable

• dependent variable

• control variable

What is being kept constant?

• ramp height
• speed of the ball rolling
• type of ball

What is being changed in this experiment?

• ramp height
• the speed that the ball rolls
• type of ball

Match the following parts of an experiment set up

• controlled variables

• things kept the same in an experiment

• dependent variable

• does NOT receive the experiment treatment

• control group

• factor that is measured

• experiment

• factor the experimenter changes

• independent variable

• procedure done to test a hypothesis

Tags

NGSS.MS-PS2-2

Match the following

• prediction

• examination to discover facts

• investigation

• interpreting the things you observe

• replication

• a different scientist conducts the same experiment

• repetition

• what will happen in the future based on evidence

• inferring

• doing multiple trials of the same experimet

Tags

NGSS.MS-PS2-2

Match the parts of a controlled experiment

• hypothesis

• explains experiment results

• conclusion

• If...then statement that gives a prediction of what will happen in the test

• repetition

• finding patterns in the data

• observation

• doing multiple trials

• analysis

• using senses to gather information

Tags

NGSS.MS-PS2-2

The summary at the end of an experiment that explains the results, and referrers to the hypothesis using data. 

• conclusion
• procedures
• materials
• responding variable