Scientific Method

Steps of the scientific method

Observe: the environmentQuestion: Recognize there is a problem

and state it in question formHypothesis- take an educated guess as to

the answerPredict what we will see if we are right or

wrongTest the predictionsDraw a conclusion

Write the template in yr NB

Observe:Question:Hypothesize:Predict:Test/ExperimentDraw Conclusion:

Observe

X-mas trees, how do we keep them alive longer?

Question

I wonder if that will work for simple plants too, like a bean plant

Hypothesize

I think it will help it grow faster

Predict

If it grows faster, it will be taller than the control , within the next 2 weeks

Test/Experiment

Get beansGet cupsLabel them:Give spriteWatch and measure growth- every other

day

Draw Conclusion

Either it did grow faster or it did not, or still grew at the same rate.Which means……

What makes a hypothesis valid?

It must be “testable” (able to be tested)Creationism: Not considered a valid

hypothesisEvolution: We evolved from a primate-like

ancestor.

What makes an experiment valid?

Observe: Many reports of cancer in people who live down the valley

Question: It’s the oldest part of Belleville, and its by the polluted Passaic River

Hypothesis: Maybe the water supply is contaminated by river water

Predict: If this is true, I will find 10 or more families down the valley, where someone has cancer

Test: I sent all the families down the valley a survey to fill out and they all sent it back

Conclusion: 10 out of 500 families there have people in the home suffering from Cancer, so our hypothesis is right

What’s wrong with this experiment?

Experimental vs. ControlControl: other areas of BellevilleVariables?Type of Water, food, radon, age-

old/young…. You have to keep everything the same

and test 1 thing at a time

There are 2 types of variables

Independent variable:Independent variable: (manipulated variable) stands alone

Dependent variable:Dependent variable: (responding variable) responds/ follows/ is expected to follow the independent variable

In the Sprite vs. water…what are we adding/controlling….

What do we expect to change because of that?....

Why do we need a control?Why do we need a control?

It validates the experiment…It establishes what is normal, or what

would have happened anyway….For comparison…

When testing medication, what is the control?

Placebo Hair re-growth pill Results: 10 men (5 got placebo and 5 got the

pill) What if 4 pill and 0 placebo re-grew hair, does it

work? What about if… 4 pill and 2 placebo re-grew hair What about if 2 placebo and 2 pill re-grew hair?

For our Sprite experiment…

How many variables should we have?

How many variables should stay the same? List them

What is the independent or manipulated variable?

What is the dependent or responding variable?

Observe:Question:Hypothesize:Predict:Test/ExperimentTest/ExperimentDraw Conclusion:

Test/ExperimentTest/Experiment

Get beans- Get cupsLabel them:Give spritePut them asideWatch and measure growth- every other

day

Observe:Question:Hypothesize:Predict:Test/ExperimentDraw Conclusion:Draw Conclusion:Sprite causes growth of bacteria and Sprite causes growth of bacteria and

fungus thereby killing the plant…fungus thereby killing the plant…

After conclusion…..Then you PUBLISH your findings in a

professional journal, in order to share your work with other scientists.

They are allowed to try to recreate your experiment… if they can’t come to the same conclusion you did, you will be considered a LIAR!!!!!