Regents Biology 2008-2009

Graphing Your Data

Showing patterns & trends

A picture is worth a

thousand words!

Regents Biology 2005-2006

Types of data (information) Variables

what you measure in an experiment dependent variable

measured variable unpredictable change: we don’t know how it

will change until we do the experiment Y-axis

independent variable manipulated variable predictable change: it only

changes because we chose how it would change

X-axis

The effect of _____________

on _____________

INDEPENDENT

DEPENDENT

Regents Biology 2005-2006

Examples of experiments 1 How does fertilizer affect the growth rate

of plants? we set up an experiment testing different

amounts of fertilizer on different plants & measuring the growth (height) of the plants: dependent variable (Y-axis)?

height of plants

independent variable (X-axis)? amount of fertilizer

The effect of _____________

on _____________

Amount of Fertilizer

Height of Plants

Regents Biology 2005-2006

Examples of experiments 2 How does exercise affect heart rate of

10th grade student? we set up an experiment testing

different lengths of time of exercise (minutes) on the heart rate of students: dependent variable (Y-axis)?

heart rate

independent variable (X-axis)? minutes of exercise

The effect of _____________

on _____________

Exercise

Heart Rate

Regents Biology 2005-2006

Examples of experiments 3 What’s the favorite drink of students?

we set up an experiment surveying students and asking which is their favorite drink : dependent variable (Y-axis)?

number of students

independent variable (X-axis)? type of drink

The effect of _____________

on _____________

Type of Drink

How many students chose it

Regents Biology 2005-2006

Making pictures out of data Graphs

line graphs graphing data that shows continuous change

bar graphs (or histograms) graphing data that is in disconnected groups

How’s a critterto choose?

Regents Biology 2005-2006

How does elevation affect temperature?

elevation

tem

pe

ratu

re

5

10

15

20

25

30

0 500 1000 1500 2000 25000

elevation (feet above sea level)

temp.

(°C)

0 30

500 25

1000 20

1500 15

2000 10

2500 5

1200 ft?

18

Line graph!

1200

Regents Biology 2005-2006

Which drink do you like best?

type of drink

nu

mb

er

of

stu

den

ts

1

2

3

4

5

6

Coke Pepsi water tea Gatorade0

drink number

Coke 1

Pepsi 1

Water 4

Iced tea 4

Gatorade 3

Red Bull?

RBRB

Bar graph!

Regents Biology 2008-2009

Any Questions??