Repeated and Replicated Review

Module: The Practice of Science

7th Grade

In Science, It is important
for a science experiment to be able to be repeated.

This makes sure that your
results are trustworthy or

valid.

Repeating the experiment
means the same person
does multiple trials of the
same experiment.

Repetition in science means that the scientist repeats the experiment in the hopes to get
the same results.

Replication is also very important in an experiment.

Why is replication important in Science?

● It's another way to ensure the validity of the
work. It is a way for scientists to “check their work”

● Repetition reduces error in an experiment.
● Less mistakes

So what is the difference between Repetition and Replication?

Replication is when another
person completes the same
experiment in the hopes to
get the same results.

Exactly 35 grams

Repetition

Replication

The same scientist conducts multiple trials of a measurement or an observation. Reduces errors in the data.

Another scientist conducts the same experiment. (redo the entire experiment). Experiment will be well accepted.

Exactly 35 grams

Multiple Choice

Steve was given a set of 5 metal cubes. Steve calculated the densities of each to determine the type of metal in each. The densities were really close to each other, so they asked Robert to do the same experiment and see if they both gets the same results.

• Repetition

• Replication

Multiple Choice

Billy is testing golf balls. They drops three different brands of balls from 40 cm and measures how high they bounce. Billy drops each ball 10 times.

• Repetition

• Replication

Multiple Choice

Dr. Smith has been reading about another scientist’s research in a physics journal. They plan to do these experiments to see if they get the same result.

• Repetition

• Replication

Multiple Choice

Julie goes to Silver River each week for 4 weeks and collects 5 samples of water to test the pH.

• Repetition

• Replication

Multiple Choice

An environmental group contacts Julie to get a record of the procedures and methods used so that they can check Julie's findings.

• Repetition

• Replication

Multiple Choice

John was mixing a batch of glue and borax solution to make silly putty and discovered a new substance that glows in the dark. John gave Ryan a copy of the specific amounts of ingredients and the procedure steps and asked Ryan to try the experiment. John plans to look at Ryan's results to see if they get the same results.

• Repetition

• Replication

Multiple Choice

Samantha has taught their pet rat to run a maze. They hypothesize that the rat will go faster if their favorite treat is at the end of the maze. 

Samantha has the rat run the maze ten times with the favorite treat at the end and ten times with a regular food pellet at the end of the maze. Samantha used a stopwatch to measure how long it took for the rat to get to the reward.

• Repetition

• Replication

● Repetition is the repeating of trials within an investigation ● Replication is the repeating of an investigation by another scientist.
○ This leads to the acceptance of evidence.