1. Types of Variables
Dependent Variable - what you measure in an experiment, graphed on the Y-axis
unpredictable change - we don’t know how it will change until we do the experiment
Independent Variable - what I change in the experiment, graphed on the X-axis
predictable change - it only changes because you made it change

2. Control
Control(s) – part of the experiment that DOES NOT change, kept constant or the same

3. Example How does fertilizer affect the growth rate of plants?
We set up an experiment testing different amounts of fertilizer on plants and measuring the growth of the plants.
Dependent variable (Y-axis)?
Height of plants
Independent variable (X-axis)?
Amount of fertilizer
Control?
Type of plant

4. Example
How does exercise affect the heart rate of a 10th grade student?
We set up an experiment testing different lengths of time of exercise on the heart rate of a student.
Dependent variable (Y-axis)?
Heart rate
Independent variable (X-axis)?
Minutes of exercise
Control?
Student

5. Example If you spend more time studying, then your grade will improve?
Dependent variable (Y-axis)?
Grade
Independent variable (X-axis)?
Amount of time spent studying
Control?
Student

6. Example
If the temperature of the room is increased, then the bacteria will grow faster.
Dependent variable (Y-axis)?
Bacterial growth
Independent variable (X-axis)?
Temperature of room
Control?
Type of bacteria

8. Create a Graphing Template
In your IAN notebook, you will create the a foldable to help you create and read graphs in this unit.
Take the 8½” x 11” sheet of paper you are given and turn it Landscape Style as shown.

9. Creating a Graphing Template
Write the follow terms at the top of each box on the doors. Leave room to define these terms in the box.
Dependent Variable
Manipulated Variable
Response Variable
Independent Variable
X - Axis
Y - Axis

10. Copy the definitions as we go thru the slides, copy what is in red.
Dependent Variable – the possible outcome of the experiment; the effect.
graphed on the Y-axis
Measured in experiment

11. Response Variable – What did I measure
Response Variable – What did I measure? What was the effect of the change?

12. Y – Axis = The Vertical Axis on a graph. Up and down, Y to the sky!

13. Manipulated, Independent Variable(control) – What did I change in the experiment? What will happen if this changes?
Graphed on X axis.

14. Independent Variable – the variable that you have control over, what you can choose and manipulate.

15. X – Axis = The Horizontal Axis on a graph, X is across.

16. Creating a Graphing Template
Graph Title
Dependent Variable (D.V.)
Manipulated Variable
Name of D.V. goes here.
Y-Axis
Independent Variable (I.V.)
Response Variable
X - Axis
Y - Axis
Name of I.V. goes here.
X - Axis
Start each axis with zero.
Each axis should be divided into even increments.
Label all parts of the graph.
Label the units of each axis.

17. Creating a Graphing Template
Close the doors to your foldable and draw the lines shown on the two doors to separate them into 3 sections each. Then write the letter shown on each section. DRY-MIX is the acronym we will use to remind you about graphing! D M
This side of the foldable gives the definition for the Dependent Variable, explains it is the Response to a change in the experiment, and shows it is located on the Y-Axis.
This side of the foldable gives the definition for the Independent Variable, explains that it Manipulates a change to the experiment, and shows it is located on the X-Axis. R I Y X

18. Creating a Graphing Template
Now paste your foldable with the DRY-MIX side up in your IAN. You should be able to open the doors and read everything that is inside! D M R I Y X

19. Types of Graphs
Line Graph – data that shows continuous change

20. Bar Graph: – data that shows no continuous change Types of graphs

21. Pie Chart Types of Graphs – data that shows percentages of a whole

22. Types of Graphs
Scatter Plot Graph-shows a relationship between two or more sets of data

23. DRY MIX Dependent Variable = Responding Variable = Y axis
Manipulated Variable = Independent Variable =I control = X axis

24. Graphing: DRY MIX
Dependent Variable
Independent Variable

25. Exit Ticket Write ALL of the following question in your IAN and answer it.
A scientist plants two rows of corn for experimentation. She puts fertilizer on row 1 but does not put fertilizer on row 2. Both rows receive the same amount of water and light intensity. She checks the growth of the corn over the course of 5 months. What is a constant in this experiment?
A. Amount of water
B. Corn without fertilizer
C. Corn with fertilizer
D. Plant height
Justify your answer:
_________________________________________________