25 terms

Interactive Science Grade 5 Chapter 1, Lesson 2

How do scientists investigate?
STUDY
PLAY
How does a scientific investigation usually begin?
Someone makes an observation.
After a scientist makes an observation, she does something. What does she do?
Asks a question and collects data.
To find reliable answers to a question, a scientist does this.
Performs an experiment.
This is the use of the scientific methods to test a hypothesis.
Definition of experiment.
A hypothesis is:
A statement of what you think will happen in an investigation.
Studies stars:
Astronomer
Studies living things:
Biologist
When scientists can't do a controlled experiment, they can:
Do one of three types of investigations- models, surveys, and sampling.
A model is:
Objects or ideas that represent other things. An example would be testing car safety with computers or a clay car.
Surveys:
Asking people questions, then recording or analyzing answers. An example would be asking all the people at a picnic what they ate and drank if people were sick.
Sampling is:
Collecting data by asking only some people at random questions. This would be asking some of the people at a picnic what they ate or drank. They would generalize the results to all the people there.
True or false: Scientists do the scientific methods in the exact same order each time.
False
True or false: Scientists may skip steps of the scientific methods.
True
Tell what step of the scientific methods is being used: IF I put lemon juice on a slice of apple THEN it will not turn brown, BECAUSE the juice keeps the apple from reacting to the air.
hypothesis
Tell what step of the scientific methods is being used: What happens if I leave an ice cube in the sun?
question
Something that can change a test is a:
variable
A variable that "stands alone" like someone's age in an experiment would be an example of an/a:
independent variable
A variable that depends on other factors. An example would be a test score because it would depend on how much you studied, if you were absent, etc.
dependent variable
True or false: A scientist should choose only one variable at a time to change so that it is a fair test.
true
A control group is:
A standard in which change is measured. An example would be giving one group of mice a vitamin and one group no vitamins and measuring any difference between the mice.
Deciding what materials to use is part of:
Making a plan to test a hypothesis.
An inference is:
Coming up with a conclusion based on our observations, data and using logic to connect ideas. An example would be: after taking data about plants, you can infer that plants grow less when given soda.
A conclusion is:
The last step of the method in which you look at all your data and use inferencing to tell if your data supports your hypothesis. An example would be: Nail polish dries faster if you spray Pam cooking spray on it, than if you leave it air dry.
True or false: In repeated trials, you change a variable each time and do the experiment a little differently each time, so that you can tell if your conclusion is valid (true).
false
True or false: It is not important if other scientists get the same results when doing experiments.
false