1. Introduction to Living Environment Scientific Method, Graphing and Measurement

2. The Scientific Method
Scientists in every country use an organized means of solving a problem. This is called the ____________ ____________.
A. There are seven steps in the Scientific Method:
1. Define the ____________. The problem is in the form of a question. Asking questions is the first step to finding answers. The question to be answered should be clearly stated.
2. Gathering ____________. Scientists would begin by researching through many means(internet, other experiments, library) to aid his quest in answering his question.(problem)
3. Form a ____________. Scientists will think of a possible answer to their problem. Such an answer is called a hypothesis or an educated guess. It is a statement!
Scientific
Method
Problem
Information
Hypothesis

3. 4. Do a ___________ ____________
4. Do a ___________ ____________. In a controlled experiment, two procedures identical in every way except one are followed. These two procedures are called:
a. ____________ group. In a control group, no changes are made. This provides an important check on the results.
b. _____________ group. In an experimental group, ONE factor is changed. The factor that is changed is called the ____________.
VARIABLES: There are actually two kinds of ____________. The variable that the experimenter changes on purpose is called the _____________ variable. The variable that is measured in the experiment is called the ____________ variable because it depends on the other variable.
Controlled
Experiment
Control
Experimental
Variable
Variables
Independent
Dependent

4. 5. Every experiment must have a list of _______________
5. Every experiment must have a list of _______________. These are all the pieces of equipment and chemicals, plants or animals you will use to perform your experiment.
materials
6. Every experiment has a written ______________ to follow also. This lists step by step how you will perform the experiment.
procedure

5. observations
6. Record ____________. Everything about the experiment should be recorded. All this information is called ____________. You might use the data to make ____________, ____________ and ____________.
observations
Graphs
Charts
tables
7. State a ____________. The answer to the problem is called the conclusion. To be valid or true the conclusion must be backed up by your experimental data.
Conclusion

6. 9. In every experiment there is always something that can be measured incorrectly or performed incorrectly. This is called a ____________ ___ ____________. Many times we list the possible sources of error at the end of our findings.
Source of
error

7. Remember the steps to the Scientific Method
Problem
Hypothesis
Materials
Procedure
Observations
Conclusion
Source of Error
You can remember them by this sentence:
Please Help My Poor Old Cat Sam

8. 10. New ____________. Research often raises new questions and new problems to be experimented on.

9. In order for an experiment to be considered VALID, The following requirements must be met:
The experiment must be ____________ several times.
The sample size must be ____________.
The sample group must be chosen at _____________.
The data collected should be a ____________ value (height, weight, color…. )
Make sure there is only one ____________.
The experiment must have a ____________ for comparison.
The procedure must explain how you will ____________ the amount of change.
Every good procedure includes ____________ ____________.
Repeated
Large
random
recordable
variable
control
measure
Safety
instructions

10. Graphing and measurement

11. Graphing Guidance
Label “0” for the origin (where the X and Y axis meet)
Label the ____________ variable on the X axis (horizontal axis)
The independent variable is what you control in the experiment (time, temperature, age, pH)
Make sure you include the units (ex: if using time indicate hours, seconds, minutes)
3. Label the ___________ variable on the Y axis (vertical axis)
The dependent variable is what you are measuring during the experiment
It depends on the independent variable
Be sure to include units (example: height in cm, mm, )
4. Number each axis appropriately
Independent
Dependent

12. ____________ each axis appropriately
Number
____________ each axis appropriately
First look at the numbers you have to graph. Find the smallest number and the largest number that has to be plotted.
Then count the number of boxes you have to use. Make a scale that will fit but use the ___________ __________ for each box. Decide whether you want to go by ones or twos or fives or tens or twenty fives and then stick to it. Each box on that axis must represent the same interval.
Follow the same steps to number the other axis. The interval will probably be different. I
If you start with a high number, you may use a break for the axis unless you are instructed not to do so.
Plot each point with a _______. Surround each dot with a __________ and connect the dots.
Give the graph a TITLE.
Same
Interval
Dot
circle

13. Y-axis
100 80
Dependent
Variable 60 40 20
X-axis 1 2 3 4 5
Independent Variable

14. Measurements in scientific investigations are usually expressed in units of the ____________________
Metric system is based on units of __________
Basic units of measurements:
Basic unit of length: _______________
Use a metric ruler to measure length
Basic unit of mass or weight: _______________
Use a triple beam balance to measure mass
Basic unit of volume: _______________
Use a graduated cylinder to measure volume
Basic unit of temperature: _______________
Use a thermometer to measure temperature
_______________ (µ or µm) most commonly used measurement when working with cells or cell parts
1 millimeter = 1000 microns (µ)
To convert millimeters to microns move the decimal point 3 places to the right (milli to mic 3 to the right)
Examples:
5 mm
5 mm
5 mm
3.2 mm
.4 mm
.4 mm
.4 mm
.01 mm
.01 mm
.01 mm