Regents Biology

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

Regents Biology

ControlControl(s) – part of the

experiment that DOES NOT change, kept constant or the same

Regents Biology

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

Regents Biology

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

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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

Regents Biology

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

Regents Biology 2005-2006

Regents Biology

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.

Regents Biology

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

Response Variable

Y - Axis

Independent Variable

Manipulated Variable

X - Axis

Regents Biology

Copy the definitions as we go thru the slides, copy what is in red.

Dependent Variable – the possible outcome of the experiment; the effect.

Regents Biology 2005-2006

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

Regents Biology 2005-2006

Y – Axis = The Vertical Axis on a graph.

Regents Biology 2005-2006

Manipulated Variable – What did I change in the experiment? What will happen if this changes?

Regents Biology 2005-2006

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

Regents Biology 2005-2006

X – Axis = The Horizontal Axis on a graph.

Regents Biology

Creating a Graphing Template

Dependent Variable (D.V.)

Response Variable

Y - Axis

Independent Variable (I.V.)

Manipulated Variable

X - Axis

Graph Title

Na

me

of

D.V

. go

es

he

re.

Name of I.V. goes here.

•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.

Y - Axis

X - Axis

Regents Biology

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

R

Y

M

I

X

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.

Regents Biology

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

R

Y

M

I

X

Regents Biology

Types of Graphs Line Graph – data that shows

continuous change

Regents Biology

Types of graphs

Bar Graph:

2005-2006

– data that shows no continuous change

Regents Biology

Types of Graphs

Pie Chart

2005-2006

– data that shows percentages of a whole

Regents Biology

Types of Graphs Scatter Plot Graph-shows a

relationship between two or more sets of data

2005-2006

Regents Biology

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

= X axis

Regents Biology

Graphing: DRY MIX

Independent Variable

Dep

end

ent

Var

iab

le