It is the process that is used to find answers to questions about the world around us.

What is the Scientific Method?

It is the process that is used to find answers to questions about the world around us.

The Scientific Method

The “tool” that scientists use to find answers to questions

Is there only one “scientific method”?

There are several versions of the scientific method

Some versions have more steps than others

They all begin with the identification of a problem or a question to be answered based on the world around us and

They provide an organized method for conducting and analyzing an experiment

5 Major Steps of the Scientific Method

1. Identify the Problem2. Form a Hypothesis3. Create and Perform an Experiment4. Analyze the Data (make conclusions)5. Communicate Results - OR- Modify

the Experiment and Start Over

1. Identify the Problem

What do you want to know or explain?

Do some research on the subject matter.

Write a question that addresses the problem or topic you want to investigate.

2. Form a Hypothesis

What is a Hypothesis? An educated guess based on

observations and your knowledge of the topic.

A testable explanation for an observation.

In other words, a suggested solution to a problem or questions

Written as an “If...then…” statement▪ Ex. IF you don’t study THEN you’ll get a bad grade on

the test

3. Create and Perform an Experiment

Follow the steps in your procedure to perform your experiment.

Record Data and Observations

What are observations? Something that you see,

feel, taste, or smell Something that can be

detected by your senses

3. Experiment - Vocabulary Control- Part of the experiment that is not

being tested and used for comparison

Variable- Any part of an experiment that can change

Independent Variable- Part of the experiment that is manipulated (what you are testing)

Dependent Variable- Part of the experiment that is affected by the change in the independent variable (what you expect to happen)

3. Experiment - Vocabulary

Validity – The procedure will accurately test the hypothesis Large sample size Adequate control (provides good

comparison) Only one variable is being tested

Reliability – when the experiment is redone, similar results are found (consistent)

3. Experiment – VocabularyLet’s practice …

Krusty Krab Breath Mints Mr. Krabs created a secret ingredient for a breath mint

that he thinks will cure the bad breath people get from eating crabby patties at the Krusty Krab. He asked 100 customers with a history of bad breath to try his new breath mint. He had 50 customers (Group A) eat the special ingredient breath mint after they finished eating a crabby patty. He had the other 50 customers (Group B) eat a regular breath mint after they finished eating a crabby patty. Both groups were told they were eating a breath mint that cures bad breath. Two hours after eating the crabby patties, 30 customers in Group A and 10 customers in Group B reported better breath than normal after eating a crabby patty.

Krusty Krab Breath Mints

5. What is the Control Group? a) Group Bb) Group Ac) Type of mintd) Curing Bad Breath

Hint- control groups DON’T have what is being tested

Krusty Krab Breath Mints

6. What is the Independent Variable? a) Group Bb) Group Ac) Type of mintd) Curing Bad Breath

Hint- the independent variable is WHAT YOU ARE TESTING

Krusty Krab Breath Mints

7. What is the Dependent Variable? a) Group Bb) Group Ac) Type of mintd) Curing Bad Breath

Hint- the dependent variable is what you expect to happen

Krusty Krab Breath Mints

8. What should Mr. Krabs conclusion be?

a) No conclusion- bad experimentb) His breath mints DO NOT cure bad

breath better than regular mintsc) His breath mints DO cure bad breath

better than regular mintsd) His breath mints actually make breath

WORSE!Last Slide

5 Major Steps of the Scientific Method

REVIEW… We have covered #1-3.

1. Identify the Problem2. Form a Hypothesis3. Create and Perform an Experiment4. Analyze the Data (make conclusions)5. Communicate Results - OR- Modify

the Experiment and Start Over

4. Analyze the Data

Charts & Graphs – This will help to organize and make sense of the data collected.

Conclusion – decided whether the original hypothesis was correct.

What is Data?

It is the information gathered during an experiment

Two main types of data Quantitative: Numerical (the most powerful

type of data)

▪ Ex. The plant grew 5 cm▪ Always measure in METRICS

Qualitative: Descriptive▪ Ex. The plant got bigger

Recording Data

Make charts, tables or graphs

Draw pictures or take photos

It is important to only state what is truly observed.

Observations VS Inferences

In our experiments, we often want to make OBSERVATIONS (not inferences) Inferences are often made after

experiments- like in the analysis or conclusion

Observations VS Inferences

Observations Any information collected with the

senses. The skill of describing scientific

events. Inferences

Conclusions or deductions based on observations

May be influenced by prior knowledge.

The process of drawing a conclusion from given evidence.

Practice: Observation vs. InferenceWrite down…A for observationB for inference

1. There is a representation of a face on one side of the coin.

2. The words printed on both sides of the coin are Latin.

3. The Latin word "Dei" means "God."4. The coin was made by deeply religious people.5. The date 1722 is printed on one side of the coin.6. The coin was made in 1722.7. The face on the coin is a representation of the

nation's president.

Make sure you know what you are observing!

OPTICAL ILLUSIONS

Is this image moving?

Are the streams moving?

How many prongs do you see?

What do you see?

Which way is the window facing?

What do you see?

Collecting and Displaying Data

Data Tables and Graphs

Artist Millions of CD’s Sold

Beatles 237.6

Elvis Presley 189.2

Michael Jackson 149.6

Queen 84.8

Variables

Ordered Pair

Units

Title

Data Table

Best Selling Music Artists

Data Table

Title- briefly describes the content of the data table

Variables- describe what information is being collected.

Units- describe the details of the information that was collected

Ordered Pairs- two pieces of data that correspond to each other.

Graphs

Used to show the relationships in data.

There are 3 main types:1. Pie2. Bar3. Line

Average Temperature and Rain in Las Vegas

Month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Rain (mm)

11.4 14.2 12.3 12.8 4.8 5.2 2.5 9.3 12.6 6.6 5.6 10.8

Temp (°C )

7.5 10.6 13.5 17.8 23.3 29.3 32.8 31.5 26.9 20.1 12.7 7.6

Using data tables to make graphs

05

101520253035

Month

Amou

nt

Rain (mm) Temp (oC)

Average Temperature and Rain in Las Vegas

Using data tables to make graphs

Make sure you include:

• Title• X Axis –

Horizontal (Variables & Label)• Y Axis –

Vertical (Variables & Label)• Key• Plot points on

the graph (clearly identified)

More About Graphs and Data TablesBigger is better when it comes to

graphsDo not forget to LABEL and TITLE

your graphs

4. Analyze the Data (make conclusions) Is the data reliable?

Reliable means if another scientist does your experiment (or you do it again), will they get similar results? ▪ If so, your experiment is reliable▪ If not, your experiment is unreliable

Does your data support your hypothesis? Your conclusion would answer this

question This is where inferences are made.

5. Communicate Results or Modify

If your data is inaccurate or your experiment is flawed…

Rewrite your procedure to address the flaws.

If your original hypothesis is not supported by your data…

Decide how you might change your hypothesis

If you believe you need more support… Think about what you might do to

experiment further and give more support to your hypothesis

5. Communicate Results or Modify

If you believe your experiment is reliable and valid Validity is concerned with the

study's success at measuring what the researchers set out to measure.

Then you can summarize the important parts of your experiment and the results

Other scientists may then verify your results by doing your experiment themselves

After the experiments…

Theory - a set of hypotheses for a general phenomenon that are supported by many experiments Theories are generally accepted

principles in science They can change based on new

evidence- but it would require A LOT of new evidence

Theories covered in Biology this year:▪ Theory of Evolution▪ Cell Theory

▪ Theory of Genetic Inheritance