Welcome to Biology. Concepts in scientific method 1 Match the word with the correct example Observation Inference Generalisation Theory Law For every.

Welcome to Biology

Concepts in scientific method 1Match the word with the correct example

• Observation• Inference• Generalisation• Theory• Law

• For every reaction there is an equal and opposite reaction.

• The leaf is green.• All living things contain cells. All

cells come from other cells.• The leaf must contain

chlorophyll.• All plant cells contain

chloroplasts.

Concepts in scientific method 1Match the word with the correct example

• Observation• Inference• Generalisation• Theory• Law

• For every reaction there is an equal and opposite reaction.

• The leaf is green.• All living things contain cells. All

cells come from other cells.• The leaf must contain

chlorophyll.• All plant cells contain

chloroplasts.

Concepts in scientific method 2

Identify the:• Hypothesis

• Independent variable

• Dependent variable

• Control

• Variables that need to be controlled

Question: Which type of insect repellent is the most effective?Experiment: Spray sticky strips with different repellents. Leave

outside for several hours. Count the number of insects that are stuck to each strip.

Concepts in scientific method 2

Identify the:• Hypothesis Brand X will repel less/more insects than Brand Y

• Independent variable brand/type of repellent

• Dependent variable insects stuck to strip

• Control sticky strip with no repellent

• Variables that need to be controlled – same size, shape & colour of strip, same amount of repellent, same temperature, humidity, location of strip

Question: Which type of insect repellent is the most effective?Experiment: Spray sticky strips with different repellents. Leave

outside for several hours. Count the number of insects that are stuck to each strip.

Dealing with data

Collecting, displaying and analysing data

Tables

• Key points:

Independent variable

Dependent variable(s)

Graphs - Key points

Title

Dependent variable 3 Grid

goes on the

Vertical axis (Y) 2 Plotted points or line or curve

Use an even scale 1

and include units

0

1 2 3 4 5

Independent variable goes on the Horizontal axis (X)

Use an even scale and include units

Graph should take up 1/2 – 2/3 of the page. Allow enough space to extrapolate the next point or two.

Types of graphs

growth of a plant

0

0.5

1

1.5

2

2.5

3

1 2 3 4 5 6 7

day

hei

gh

t (c

m)

height (cm)

types of trees in the school

0

2

4

6

8

10

12

14

16

18

bank

sia

bottl

ebru

sh

euca

lypt

gras

s tre

e

wattle

type of tree

nu

mb

er

numbers

fruit production in tomatoes

0

2

4

6

8

10

12

14

0 - 0.5 0.6 - 1.0 1.1 - 1.5 1.6 - 2.0

weight of fruit harvested

nu

mb

er o

f p

lan

ts

number

height and weight

0

10

20

30

40

50

60

70

0 0.5 1 1.5 2

height (m)

wei

gh

t (k

g)

Line graphsgrowth of a plant

0

0.5

1

1.5

2

2.5

3

1 2 3 4 5 6 7

day

hei

gh

t (c

m)

height (cm)

• used to plot continuous data• used to look for relationships where one affects

the other

Column or Bar graphs

• used to plot discontinuous data (categories)• used to show how many in each category

types of trees in the school

0

2

4

6

8

10

12

14

16

18

bank

sia

bottl

ebru

sh

euca

lypt

gras

s tre

e

wattle

type of tree

nu

mb

er

numbers

Histogramsfruit production in tomatoes

0

2

4

6

8

10

12

14

0 - 0.5 0.6 - 1.0 1.1 - 1.5 1.6 - 2.0

weight of fruit harvested

nu

mb

er o

f p

lan

ts

number

• used for grouped data

Scatter graphs

• used for look for relationships

height and weight

0

10

20

30

40

50

60

70

0 0.5 1 1.5 2

height (m)

wei

gh

t (k

g)

Day Height (cm)

1 64

2 68

5 92

7 110

10 134

12 140

14 152

17 160

18 162

20 168

Growth of a plant

Growth of plant

0

20

40

60

80

100

120

140

160

180

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Day

Hei

gh

t (c

m)

Height (cm)

Birds seen at school

Galah 4Raven 7Pigeon 6Wattle bird 3Willie wagtail 1

Birds seen at school

0

1

2

3

4

5

6

7

8

Galah Raven Pigeon Wattle bird Willie wagtail

Type of bird

Nu

mb

er o

f b

ird

Height (m) Number of

students

139 140 – 149

2 1

150 - 159 2

160 - 169 3

170 - 179 1

180 - 189 1

190 - 199 1

200 0

Number of students of different heights

0

0.5

1

1.5

2

2.5

3

3.5

<139 140– 149

150 - 159 160 - 169 170 - 179 180 - 189 190 - 199 >200

Height (cm)

Nu

mb

er o

f st

ud

ents

Number of students

Student Height (m)

Leg length

(m)

10 steps (m)

1 1.64 0.97 5.9

2 1.67 1.05 7.45

3 1.54 0.93 6.1

4 1.49 0.91 6.78

5 1.83 1.02 6.58

6 1.76 1.0 8.0

7 1.53 0.87 6.5

8 1.91 1.07 10.1

9 1.68 0.95 6.45

10 1.44 0.79 5.7

height vs 10 steps

0

24

6

810

12

0 0.5 1 1.5 2 2.5

height

10 s

tep

s

10 steps (m)

leg length vs 10 steps

0

2

4

6

8

10

12

0 0.2 0.4 0.6 0.8 1 1.2

leg length (m)

10 s

tep

s (m

)

10 steps (m)