Intro & Investigation vocab and practice

Steps to the Scientific Method

1. Make an observation and ask a question 2. Form a hypothesis (a proposed answer to a scientific question) 3. Perform an experiment 4. Analyze your data (determine what the data means through graphs, charts, calculations, etc...) 5. Conclude- Was the hypothesis correct?

Variable

A factor in an experiment that can be changed

Plant A

A scientist who wants to study the affects of fertilizer on plant growth sets up an experiment. Plant A gets no fertilizer, Plant B gets 5 mg. of fertilizer each day, and Plant C gets 10mg. of fertilizer each day. All plants receive the same amount of sunlight and water. What is the control group?

Plant growth

A scientist who wants to study the affects of fertilizer on plant growth sets up an experiment. Plant A gets no fertilizer, Plant B gets 5 mg. of fertilizer each day, and Plant C gets 10mg. of fertilizer each day. All plants receive the same amount of sunlight and water. What is the dependent variable?

sunlight, water, # of plants

A scientist who wants to study the affects of fertilizer on plant growth sets up an experiment. Plant A gets no fertilizer, Plant B gets 5 mg. of fertilizer each day, and Plant C gets 10mg. of fertilizer each day. All plants receive the same amount of sunlight and water. What is the dependent variable?

Plants B & C

A scientist who wants to study the affects of fertilizer on plant growth sets up an experiment. Plant A gets no fertilizer, Plant B gets 5 mg. of fertilizer each day, and Plant C gets 10mg. of fertilizer each day. All plants receive the same amount of sunlight and water. What is the experimental group?

Fertilizer

A scientist who wants to study the affects of fertilizer on plant growth sets up an experiment. Plant A gets no fertilizer, Plant B gets 5 mg. of fertilizer each day, and Plant C gets 10mg. of fertilizer each day. All plants receive the same amount of sunlight and water. What is the independent variable?

Hypothesis

A tentative explanation to a problem that is based on research, or a proposed answer to a scientific question; an "educated guess"; written in an "If _____then_____ statement" Example: If a plant is given sunlight then it will grow taller than a plant given no light

Controlled Experiment

An experiment that has only one variable tested while everything else remains the same. example: Testing the effect of salt water versus fresh water in an experiment

Analysis/Analyze

Determine what your data MEANS through charts, graphs, calculations, etc....

Conclusion

Determine whether or not your hypothesis was correct, back it up with evidence and provide a reason

Control Group

Group in an experiment that does not have a variable and used as a comparison; the "normal standard" to compare the experimental group to example: Nothing was changed in the experiment for the mushrooms on the right

Experimental Group

The EXPERIMENTAL GROUP is identical to the control group except for one variable which is changed This is the group getting the "treatment" Example: The plants on the left in the picture were given special fertilizer and therefore are the experimental group. The plants on the right did not get the special fertilizer and therefore were the control group.

Control Variables/Constants

The factors that stay the same between the control and experimental groups are called Example: If you are testing the effect that sunlight has on plant growth, the controls would be the amount of water the plants get get, the type of plant tested, the size of the pot, the amount of soil, etc.. These factors you would keep the same between all test groups.

Independent Variable

The one variable that you CHANGE in a controlled experiment; the "treatment" ex: Changing the amount of light a plant receives

Dependent Variable

The outcome of a controlled experiment; what you are MEASURING. example: HOW MUCH A PLANT GROWS when you change the amount of light it receives

Observation

information gathered by the senses and/or with tools