Performing an experiment multiple times in the same conditions to see if the results are the same
What is repetition?
Sue is conducting an experiment. She takes four plants, gives one no water, one 1 cup of water a week, one 2 cups of water a week, and one 3 cups of water a week. She gives each plant the same soil, fertilizer, and sunlight. Sue measures how much each plant's height changes once a week. Her test variable (independent variable) is :
Ian reads a scientific article every day, demonstrating this step in the scientific method.
What is doing research / gathering information?
This branch of science is often studied using computers for modeling, physical models of the solar system, and telescopes to observe things that are far away.
What is astronomy? (Earth space science)
Phil was murdered! Forensic investigators perform tests of his hair, skin, and blood to check for DNA. They should complete multiple repetitions for this reason.
What is to show the results are valid?
Having a different experimenter perform the same experiment with the same conditions to see if the results are the same.
What is replication?
Sue is conducting an experiment. She takes four plants, gives one no water, one 1 cup of water a week, one 2 cups of water a week, and one 3 cups of water a week. She gives each plant the same soil, fertilizer, and sunlight. Sue measures how much each plant's height changes once a week. Her constants are:
What are the soil, the fertilizer, and the sunlight?
Isaac thinks, "Why do apples fall down instead of up?" Isaac is doing this step in the scientific method.
What is asking questions?
Computers are often used to sort data into neat columns which make it easier to read, called this.
What is a data table?
Abby wants to know if her soup is poisoned. She takes poison and measures its pH, then takes the pH of unpoisoned soup. Finally, she measures the pH of her soup. What is the control group in her investigation?
What is the unpoisoned soup?
Its purpose is to help show that the results are accurate and valid because one person can get the same results multiple times.
What is repetition?
Sue is conducting an experiment. She takes four plants, gives one no water, one 1 cup of water a week, one 2 cups of water a week, and one 3 cups of water a week. She gives each plant the same soil, fertilizer, and sunlight. Sue measures how much each plant's height changes once a week. Her outcome variable (dependent variable) is :
What is the change in the plant's height?
Isaac sits under a tree daydreaming. He notices an apple fall. What step in the scientific method is Isaac doing?
What is an observation?
This type of graph shows changes over a long period of time for a test (independent) variable that does not fit into distinct categories.
What is a line graph?
Joseph performs an experiment to see if blood reacts with an antibody. He compares this to blood mixed with a different antibody, which is this kind of scientific inquiry.
What is a comparison?
Its purpose is to help show that the results are accurate and valid because different person can get the same results multiple times.
What is replication?
Betsy is testing if bacteria will mutate after being exposed to different substances. Betsy has 12 groups of E-Coli bacteria that will not grow in Agar unless they mutate. She puts 3 in Agar with Laundry detergent A, 3 in Agar with Laundry detergent B, 3 in Agar with Laundry detergent C, and 3 in Agar. Betsy measures the number of bacteria colonies after 1 week. Betsy's control group is this.
What are the bacteria in agar alone?
Skylar puts mice on a raised platform after giving them a drug. She measures how much time they spend hiding vs. on the open arms. She then compares these results to the results of mice that were not given a drug before being put on the platform. Skylar is doing this step in the scientific method.
What is a controlled experiment?
The change in average global temperature is shown in the chart below. This culd be driving that increase.
What is an increase in carbon dioxide in the atmosphere?
Lori is testing to see how insects can interact with ecosystems. She counts the number of insects in a wooded area one morning, then the number of insects in an open area in the evening. A problem with this investigation is this.
What is changing multiple things at a time or not doing repetitions?
Joseph performs an experiment to test if potatoes grow better sitting on his desk or buried in dirt. He takes two potatoes, cuts each into 8 identical pieces, and buries 8 in dirt while leaving 8 on his desk. The purpose of cutting each potato into 8 is this.
What is repetition to show his results are valid?
Betsy is testing if bacteria will mutate after being exposed to different substances. Betsy has 12 groups of E-Coli bacteria that will not grow in Agar unless they mutate. She puts 3 in Agar with Laundry detergent A, 3 in Agar with Laundry detergent B, 3 in Agar with Laundry detergent C, and 3 in Agar. Betsy measures the number of bacteria colonies after 1 week. Betsy's test variable (independent variable) is this.
What is the type of laundry detergent used?
CJ performs a test to see if DNA can be isolated from fruit flies using a particular chemical. His result does not match up with those of other scientists. His immediate next step should be this.
What is repeat the experiment several more times to see if he gets the same result?
Geologists often analyze rocks to determine how old they are. They use relative dating, where they determine which kind is older, and absolute dating, such as this method shown below.
What is radioactive/radiometric dating?
These are the coolest science teachers.
Who are Coach Rubin and Ms. Sandum?