Aim#5: What are the scientific methods used for Research?Textbook: 1.1-1.2 (p. 4-15)

9-17-13

H.W. Characteristics of Life Quiz:Period 2/3- Friday 9/12Period 8/9- Thursday 9/11

9/16-9/17: HW#4________ Complete the Web Activity: Characteristics of Life. Choose ANY 3 organisms and research how they carry out each of the characteristics listed on the handout. Please complete for Friday 9/12.

#5:Scientific Inquiry and the

Scientific Method

How does a hypothesis guide research?

Aim Log:

Aim#5: What are the scientific methods used for Research?

9-18-13

#5:Scientific Inquiry and the

Scientific Method

How do you design a reliable science experiment? How is the conclusion of a science experiment beneficial to scientists?

HW#5 _______Read p.4-15 in your textbook.  Define the following terms, and give an example of each term ON YOUR VOCABULARY LIST: theory, science, pseudoscience, peer review, dependent variable, independent variable, observation, inference, hypothesis. (pseudoscience is not on your vocabulary list, please add it to the bottom).

1. What is Scientific Inquiry:

• Development of explanations and theories

• Based on unbiased observations and explanations

-How do you know whether to believe headlines like the one to the left of not?

-How do you know when to trust claims in advertisements, on tv, on the internet, in newspapers, or in a magazine?

- What makes something science-based?

-How do you know whether to believe headlines like the one to the left of not?

-How do you know when to trust claims in advertisements, on tv, on the internet, in newspapers, or in a magazine?

- What makes something science-based?

-How do you know whether to believe headlines like the one to the left of not?

-How do you know when to trust claims in advertisements, on tv, on the internet, in newspapers, or in a magazine?

- What makes something science-based?

Scientific Method songs

• http://www.youtube.com/watch?v=jPaGOHwv7mQ

• http://www.youtube.com/watch?v=MV8lSmIo4Ac (Nelly)

2) Observation vs Inference2) Observation vs Inference

OBSERVATIONOBSERVATION Information we Information we

gather using our gather using our sensessenses

An interaction An interaction between your between your senses and the senses and the environmentenvironment

How do we make observations How do we make observations more accurate?more accurate?

InstrumentsInstruments extend our extend our senses and make senses and make observations more accurateobservations more accurate

Examples:Examples: RulersRulers MicroscopesMicroscopes TelescopesTelescopes ThermometerThermometer

2) Observation vs Inference2) Observation vs Inference

INFERENCEINFERENCE A conclusion based on an A conclusion based on an

observation; previous knowledgeobservation; previous knowledge

The more observations you make, The more observations you make, the more accurate your inferences the more accurate your inferences will be.will be.

Note the DifferencesNote the Differences

In laboratory exercises, In laboratory exercises, record observations record observations NOTNOT inferencesinferences

Let’s test your observation Let’s test your observation skills…skills…

“And Now Edgar is gone… Something’s going on around here”

Observations can be difficult at times…Observations can be difficult at times…

How many legs does the elephant How many legs does the elephant have?have?

What do you see? What do you see?

What animal do you perceive?What animal do you perceive?

A Duck, Bunny, or BOTH?

Ask a Question

Observations vs. Inferences

You can observe a lot just by watching!

You can observe a lot just by watching!

Qualitative Observation-

Quantitative Observation-

Observations-Use 5 senses to notice surroundings

Inference- decisions based on observations

Descriptions, shape, color, etc.

Numbers and Measurements

Make at least 2 quantitative and 2 qualitative observations about the

picture below

Experimental Questions must be testable:

Which of these is testable?

Does the Universe end?

Does drinking soda make you fat?

Answer the following questions based on the picture:

• Are there cars parked on the side of the road?

• What color is the pickup truck driving in the road?

• Any minivans around?

• What does the blue sign say?

• What’s the speed limit?

• Are there any pedestrians on the road?

– Go back to picture and make 2 inferences based on your observations above.

Aim#5: What are the scientific methods used for Research?

HW#6________Read the Key Concepts (1.1-1.3) on p. 26-27.  Please write the questions and the answers to the following questions:

p. 28:  7,9,10,12 p. 29: 19,22,29

#5:Scientific Inquiry and the

Scientific Method

Why is Peer Review an important step in the scientific method?

1. The boy is in the water.2. The weather is cold.3. The tree branch is

broken.4. The boy fell off the

branch.5. A goat is standing by the

pond.6. The boy fell off the rocks.7. There is a sailboat in the

water.8. The sailboat belongs to

the boy.9. The tree by the pond has

no leaves.10. There are three rocks in

the pond.11. The tree on the pond is

dead.12. If it rains leaves will grow

on the tree.

Scientific MethodScientific Method

Experimental DesignExperimental Design

What is the Scientific What is the Scientific Method?Method?

Scientists follow a set of steps in Scientists follow a set of steps in order to answer questions about order to answer questions about the world around them.the world around them.

There are 6 steps to the Scientific There are 6 steps to the Scientific Method.Method.

1. State the Problem1. State the Problem2. Form a Hypothesis2. Form a Hypothesis

3. Experiment and Observe3. Experiment and Observe4. Organize the Data4. Organize the Data

5. Interpret the data (inference)5. Interpret the data (inference)6. Draw Conclusions6. Draw Conclusions

1. State the Question or 1. State the Question or ProblemProblem

What are you trying to find out?What are you trying to find out?

Can you develop an experiment to Can you develop an experiment to answer your question?answer your question?

Research the topic using reliable Research the topic using reliable sources sources

Reliable: scientific journalsReliable: scientific journals Not reliable: WikipediaNot reliable: Wikipedia

2. Form a hypothesis2. Form a hypothesis

A hypothesis is an educated guess. It is A hypothesis is an educated guess. It is what you think will happen. BASED ON what you think will happen. BASED ON OBSERVATIONOBSERVATION

The hypothesis is The hypothesis is alwaysalways a statement, a statement, nevernever a question a question

Write it as an if/then statementWrite it as an if/then statement– Ex: If a plant is exposed to more light, then it will grow Ex: If a plant is exposed to more light, then it will grow

faster.faster. ~ “If (Independent variable), then (dependent variable)”~ “If (Independent variable), then (dependent variable)” ~ “If (cause-I perform this action), then (effect-I expect ~ “If (cause-I perform this action), then (effect-I expect

this outcome)”this outcome)”

3. Design an Experiment3. Design an Experiment

An experiment is a step by step An experiment is a step by step procedure used to test a hypothesis procedure used to test a hypothesis and find an answer to a question.and find an answer to a question.

The experiment must be detailed The experiment must be detailed and specific. Write it out in a and specific. Write it out in a numbered list numbered list ex: 1.ex: 1.

2.2.3.3.

3. Design an Experiment3. Design an Experiment

What materials will be used and what What materials will be used and what safety precautions will be followed?safety precautions will be followed?

How will you collect data?How will you collect data?

How many subjects will be used?How many subjects will be used?

How do make sure your data is valid?How do make sure your data is valid?– Repeated trialsRepeated trials– Use large numbers of subjectsUse large numbers of subjects

4. Collect and Organize Data4. Collect and Organize Data

Gather data throughout the Gather data throughout the experiment through observationsexperiment through observations

Keep data organized in tables and Keep data organized in tables and chartscharts

5. Analyze and Interpret Data5. Analyze and Interpret Data

Analyze data to see trends in dataAnalyze data to see trends in data Graphs – line and bar graphs. Graphs – line and bar graphs.

– Always use pencilAlways use pencil

6. Form a conclusion6. Form a conclusion

What happened in your experiment?What happened in your experiment?

Does the data support or refute the Does the data support or refute the hypothesis?hypothesis?– The data __________ my hypothesis. The data The data __________ my hypothesis. The data

showed ___________.showed ___________.

Identify unexpected results.Identify unexpected results.

Are your results reliable? Are your results reliable? – Can they be duplicated by other scientists?Can they be duplicated by other scientists?

Future experimentsFuture experiments

Did the experiment’s conclusion lead Did the experiment’s conclusion lead to more questions? The cycle can to more questions? The cycle can begin again.begin again.

Aim#5: What are the scientific methods used for Research?

HW#

#5:Scientific Inquiry and the

Scientific Method

What are the necessary components of a controlled experiment?

Controlled Experiments:

Control vs. Experimental groups:

Independent vs. Dependent Variables:

Constants (controlled variables):

What makes pill bugsan example ofa good experimental organism?

1) Key Vocabulary

There are 2 Groups in an experiment:

1. Control Group – the subjects who are kept under “normal” conditions. – Used as a basis for comparison.

2. Experimental Group – the subjects who are being tested.

1) Vocabulary

There are 2 Variables in an experiment:

1. Independent Variable – the part of the experiment that is controlled by the person conducting the experiment.- “I” can change the independent variable.

2. Dependent Variable – the data that is being collected in the experiment.

1) Vocabulary

• Constant: any other factor in an experiment that remains the same throughout.

Ex: testing how length of light affects plant growthconstants: amount of water, type of plant used, temperature of room

2) PracticeLet’s put our knowledge of the Scientific

Method to a realistic example that includes some of the terms you’ll be

needing to use and understand.

John watches his grandmother bake bread. He ask his grandmother what

makes the bread rise.

She explains that yeast releases a gas as it feeds on sugar.

John watches his grandmother bake bread. He ask his grandmother what

makes the bread rise.She explains that yeast releases a gas as

it feeds on sugar.• Design an investigation to test this Design an investigation to test this

hypothesis.hypothesis.

– Identify the variablesIdentify the variables

– What exactly will be changed? How What exactly will be changed? How will it be changed?will it be changed?

– What exactly will be measured? What exactly will be measured? How will it be measured?How will it be measured?

Problem/Question

John wonders if the amount of sugar used in the recipe will affect the size of the bread

loaf?

Observation/Research

John researches the areas of baking and

fermentation and tries to come up with a way

to test his question.

He keeps all of his information on this topic in a journal.

Formulate a Hypothesis

After talking with his teacher and

conducting further research, he comes

up with a hypothesis.

“If more sugar is added, then the bread will rise

higher.”

Hypothesis

The hypothesis is an educated guess about the relationship

between the independent and dependent variables.

Note: These variables will be defined in the next few slides.

Independent Variable The independent variable, is a factor that’s intentionally varied

by the experimenter.John is going to use 25g., 50g.,

100g., 250g., 500g. of sugar in his experiment.

Dependent Variable The dependent variable is the

factor that may change as a result of changes made in the independent variable. This is

your data.In this case, it would be the size

of the loaf of bread.

Control Group

In a scientific experiment, the control is the group that serves as the standard of comparison.

The control group may be considered the normal situation

where nothing has been changed.

Control Group

The control group is exposed to the same conditions as the

experimental group, except for the variable being tested.

All experiments should have a control group.

Control Group

Because his grandmother always used 50g. of sugar in

her recipe, John is going to use that amount in his control

group.

Constants

John’s teacher reminds him to keep all other factors the same so that any observed

changes in the bread can be attributed to the variation in the amount of sugar.

Constants

The constants in an experiment are all the

factors that the experimenter attempts

to keep the same.

Can you think of some Can you think of some constants for this constants for this

experiment?experiment?

ConstantsThey might include:

Other ingredients to the bread recipe, oven used,

rise time, brand of ingredients, cooking time,

type of pan used, air temperature and humidity

where the bread was rising, oven temperature,

age of the yeast…

TrialsTrial number is how many

times you performed the experiment.

The more trials you have, the more reliable you

can consider your results.

John is going to test each sugar variable 3 times.

Collect and Analyze Results

John comes up with a table he can use to record his data.John gets all his materials together and carries out his

experiment.

Size of Baked Bread (LxWxH) cm3

Amt. of Sugar (g.)

1 2 3 AverageAverage

Size (cmSize (cm33))

25 768 744 761 758

50 1296 1188 1296 1260

100 1188 1080 1080 1116

250 672 576 588 612

500 432 504 360 432

Size of Bread Loaf (cmSize of Bread Loaf (cm33))

TrialsTrials

Control group

Collect and Analyze Results

John examines his data and notices that

his control worked the best in this

experiment, but not significantly better

than 100g. of sugar.

Conclusion

John rejects his hypothesis, but

decides to re-test using sugar

amounts between 50g. and 100g.

Experiment

Once again, John gathers his materials and carries out his

experiment.

Here are the results.

Size of Baked Bread (LxWxH) cm3

Amt. of Sugar (g.)

1 2 3 AverageAverage

Size (cmSize (cm33))

50 1296 1440 1296 1344

60 1404 1296 1440 1380

70 1638 1638 1560 1612

80 1404 1296 1296 1332

90 1080 1200 972 1084

Size of Bread Loaf (cmSize of Bread Loaf (cm33))

TrialsTrials

Control group

Conclusion

John finds that 70g. of sugar produces

the largest loaf.

His hypothesis is accepted.

Communicate the Results

John tells his grandmother about

his findings and prepares to present

his project in Science class.

Look at each of the hypotheses below. Identify the independent and dependent

variables. Give a brief description of how you would test each.

1. If we add salt to soil, then plants will grow more leaves.

2. If we change the color of light, then a plant will grow taller.

3. If we increase the temperature, then bacterial growth will increase.

4. If plants are exposed to low temperatures, then there will be changes in leaf color.

5. If people are exposed to a high amount of UV light, then there will be a higher frequency of skin cancer.

Suppose you work for a Blabbit Labs, thedeveloper of many different pharmaceuticalproducts. Your research division has stumbledacross a new drug that you believe cures malepattern baldness. Before you can start selling thedrug, you must demonstrate to the U.S. Food andDrug Administration that the drug is effective.

1. What is the question/problem being asked?

2. Form a hypothesis for your experiment.

You design an experiment with 500 men who have been diagnosed with male pattern baldness. They are divided up into two groups, group A (men receiving the drug) and group B (men receiving a placebo).

3. Control Group-

4. Experimental Group-

5. Independent Variable-

6. Dependent Variable-

7. Constants-

3. Theory: • An explanation of a natural phenomenon supported by many observations (evidence) and experiments over time

• It can be revised as new evidence becomes available

*What are some examples of theories?

4. What is a LAW??- a summary of observed experimental

facts that is always truealways true.

5. Science vs. Pseudoscience:

• Imitate science but do not provide science-based explanations about the natural world

6. How do we know

information is science-based?

– Expand scientific knowledge

– Challenge theories and results (testable)

– Test claims

– Peer Review

– Uses metric system

7. Science in Every Day Life

• Ethics: moral values or principles• Ethical issues in science today:

*Exit Ticket:

• Bart believes that mice exposed to microwaves will become extra strong (maybe he's been reading too much Radioactive Man). He decides to perform an experiment by placing 10 mice in the microwave for 10 seconds. He then compared the performance of these 10 mice to another 10 mice that had not been exposed to the microwaves. His test consisted of a heavy block of wood that blocked the mouse from food. He found that 8 out of 10 of the microwaved mice were able to push the block away to get to the food. 7 out of 10 of the non-microwaved mice did the same.

- Identify:

– Control group-

– Independent variable-

– Dependent variable-

– What should Bart’s conclusion be?

– How can he improve this experiment?

– What are the ethical considerations in this experiment?

The Scientific Method in Action

• Do all scientific experiments occur in a lab?

– Field Studies

• http://app.discoveryeducation.com/player/view/assetGuid/84E4BD2D-33C9-4973-9058-39F4C413E7E5 (Yellow Fever and Dr. Walter Reed)

* Pill Bug Lab- Part 2Experimental Design Discussion

• With a partner, you have 5 minutes to discuss and design a well-written hypothesis for future research of pill bugs.

• Write your hypothesis NEATLY on the white board provided and attach it to the front board