Fortune Telling Fish Why does the fish move

Experiments for testing Temp explanation, are they controlled? Warm hand, cold table? Results –

Conclusion Is the data reliable? Did we collect enough data? (trials) Was the experiment

The Miracle of Penicillin Alexander Fleming

Grew Bacteria on Agar plates Different colonies/species Bacterial “lawn” Bacteria being inhibited by mold

Possible Explanations - Hypothesis Mold is eating bacteria Hypothesis: If/then/because Mold’s waste is killing

Controlled Experiment: Independent & Dependent Variables, Control & Variable groups, Controlled variables Independent: what

Controlled Variables Same type of broth Same type of bacteria Same temperature Same type

Results – Collecting DATA Qualitative Quantitative Written Numbers description color of colonies, smell, photos

Conclusion The hypothesis that mold produces a toxin that kills bacteria is supported. On

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Fortune Telling Fish: Why does the fish move differently? Observations Explanations – Called what in science? Movement Temperature Red Surface Writing on it Static electricity Cellophane Moisture Translucent Lighting

Experiments for testing Temp explanation, are they controlled? Warm hand, cold table? Results – DATA Warm water, cold water? Qualitative? Warm with light bulb, ice cube? Quantitative? Tables? Several trials? Joe’s warm hand, Jill’s cold hand?

Conclusion Is the data reliable? Did we collect enough data? (trials) Was the experiment controlled and error free? Supported or Unsupported, not proven, correct, right or wrong. If not what other hypothesis can we test?

The Miracle of Penicillin Alexander Fleming

Grew Bacteria on Agar plates Different colonies/species Bacterial “lawn” Bacteria being inhibited by mold - penniclium

Possible Explanations - Hypothesis Mold is eating bacteria Hypothesis: If/then/because Mold’s waste is killing bacteria Mold is a better competitor of nutrients, thereby bacteria starve If there is mold present then it will produce a toxin that will kill the bacteria because the toxin will prevent the bacteria from reproducing. Mold is producing a toxin that kills bacteria Brainstorm a list and perform controlled experiments on each.

Controlled Experiment: Independent & Dependent Variables, Control & Variable groups, Controlled variables Independent: what is changed (manipulated) Dependent: what is measured (responding) Control group: no exposure to treatment Variable groups: exposed to various treatments Controlled variables: All other factors in the experiment are kept the same.

Controlled Variables Same type of broth Same type of bacteria Same temperature Same type of agar Grow for the same amount of time Do same number of trials (min = 3)

Results – Collecting DATA Qualitative Quantitative Written Numbers description color of colonies, smell, photos for averaging & graphing Ave control plates: 100 colonies Ave variable plates: 3 colonies

Conclusion The hypothesis that mold produces a toxin that kills bacteria is supported. On average only 3 colonies of bacteria remain, versus 100 s when no mold is present. Repeat, Repeat Others Repeat from around the world When hypothesis survives repeated testing it is now considered a THEORY