The Goals of Science – The physical universe is a system composed of parts and processes that...

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The Goals of Science – The physical universe is a system composed of parts and processes that

interact. All objects in the universe, and all interactions among those objects, are governed by universal natural laws.

–provide natural explanations for events in the natural world through observation.

– Science also aims to use those explanations to understand patterns in nature

–make useful predictions about natural events.

Learning about science means understanding

what we know… and what we don’t know.

Science rarely“ proves” anything in absolute terms.

Scientists aim for the best understanding of the

natural world that current methods can reveal.

Scientists propose explanations that are

based on evidence, not belief. Then they test

those explanations with more evidence.

Scientific Methodology: The Heart of Science

– What procedures are at the core of scientific methodology?

– Scientific methodology involves observing and asking questions, making inferences and forming hypotheses, conducting controlled experiments, collecting and analyzing data, and drawing conclusions.

Common Theory vs Scientific Theory a hunch or guess.

What a scientist would call a hypothesis.

A well tested explanation that tiestogether many hypotheses allowingscientist to make accurate predictionsabout new situations.

There are six steps to the scientific Method

Use your senses to find out what’s

going on.

Step 1 Step 2 Step 3

Step 5 Step 4Step 6

Make Observations State the Problem Form a Hypothesis

Make a Conclusion Record &Analyze Experiment

going on.

What is it that youdon’t like

Step 5 Step 4Step 6

. Use your senses to

find out what’s going on.

Use IF to tell what to do to solve the problem

and THEN to state what you think will happen

Step 5 Step 4Step 6

going on.

Perform your hypothesis

Step 5 Step 4Step 6

going on.

Write or chartwhat happened

Step 5 Step 4Step 6

going on.

Did the experimentsupport the hypothesis

Step 5 Step 4Step 6

Where do maggots come from?

In the past people did not know. Somethought they just appeared spontaneouslywithout any cause…Were they right? How could you find out?

List and label the IV, independent variable or (manipulated variable) in Redi’s experiment.

Independent Variables = IV(manipulated variables) (do their own thing…What’s different?)

Gauze coveringadded to 1 set of jars keeps flies away from meat is different. next

What would the DV, dependent variable in Reddi’s experiment be?(the response to the the IV)

DV = response to the IV :whether or not the maggots appear

What would the DV, dependent variable be?(the response to the the IV)

Control Variables (Stay the same)jars, type of meat,location, temperature,time

Independent orManipulated Variables: (do their own thing…What’s different?)

gauze coveringthat keeps flies away from meat.

DV= responding Variable: whether maggots appear

What does a scientist do if the experiment refutes the hypothesis (does not supportthe hypothesis)?

1. Check that they did the experiment correctly.2. Check the hypothesis

This summer did you put on sun block and stillget a sunburn?

How could we use the scientific method to test if sun blockreduces UV exposure?

How do you know there is a problem.

Step 5 Step 4Step 6

UV radiation causes sunburn

How do you know there is a problem.

Step 5 Step 4Step 6

Sunburn leadsto skin cancer

time no block block

going on.

Step 5 Step 4Step 6

If I use sun blockthen I won’t get asmuch UV radiation

time no block block

OBSERVATIONS: Flies land on meat that is left uncovered. Later, maggots appear on the meat.

HYPOTHESIS: Flies produce maggots.PROCEDURE

Controlled Variables:jars, type of meat,location, temperature,time

Manipulated or Independent Variables:gauze covering thatkeeps flies away from meat

Uncovered jars Covered jars

Several days pass

Maggots appear No maggots appearResponding or Dependent Variable: whether maggots appear

CONCLUSION: Maggots form only when flies come in contact with meat. Spontaneous generation of maggots did not occur.

Section 1-2

Go to Section:

The Scientific Method changes just 1 variable ata time.

Change just 1 thing in your sun block experiment.

going on.

How many seconds did it take your bead ___

Step 5 Step 4Step 6

Expose 2 UV sensitivebeads to UV after coating one beadwith sun block

time no block block

going on.

Step 5 Step 4Step 6

I don’t want to burn

# changed/time no block

going on.

Step 5 Step 4Step 6

I don’t want to burn

#Changed/time DVno block

I V Yes… it took longer to get the same UV exposure with sun block

When starting an experiment design a Data Table to record your observationsin a useable way.

The first column of a data table uses the independent variable as it’s heading.

The dependent variable is the heading for next column.

Make a linear graph of the results over time.

fill 2 lines, one for sun block and another for no sun block

Include the following • Full Title• Label for the X & Y axis• Key for colors or shapes for block & no block

No block Sun block

Independent Variable(manipulated)

Dependent Variable (Responding)

# of beadsthat changed

Time till# beads changed

The title for an experiment states the Affect of the IV on the DV

The Affect of Sun Block on Exposure toUV Radiation

This is the process that all scientists follow so their experiments are documented and repeatable…

even though decadesor centuries may have passed.

The Goals of Science – The physical universe is a system composed of parts and processes that...

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