THE SCIENTIFIC METHOD. HYPOTHESIS Tentative explanation to account for an observation Testable ...
Transcript of THE SCIENTIFIC METHOD. HYPOTHESIS Tentative explanation to account for an observation Testable ...
HYPOTHESISTentative explanation to account for an observation
Testable
Falsifiable
In accord with all dataCannot be proven!
Fairies cause warts.Toads cause warts.
HYPOTHESISHypothesis making and testing
Inductive reasoning
•Take many specific facts to come up with a general statement
Deductive reasoning
•If . . . . then . . .
HYPOTHESISHypothesis making
Inductive reasoning
•Specific General
Facts: Bacteria are made of cells, plants are made of cells, and animals are made of cells
Hypothesis: All organisms are composed of cells.
HYPOTHESISHypothesis testing
Deductive reasoning
•General Specific
Hypothesis: All organisms are composed of cells
Test: If all organisms are composed of cells, then fungi and
protist should be made of cells.
THE TESTExperiment or Observation
You can't prove your hypothesis, but you can disprove your null hypothesis
H0 versus H1
EXPERIMNENTAL DESIGNChange only one variable
Experimental Variable
Dependent Variable
Have something to compare it to
Experimental Groups
Control Groups
Numbers
Quantify data
Have replicates
PUBLISH YOUR DATAPrimary publication
Peer review
Evaluate, confirm, repeatReview articles
Popular literature
Characteristics of the rhizobia associated with Dalea spp. in the Ordway, Kellogg–Weaver Dunes, and Hayden prairies
Prevalence and airborne spore levels of Stachybotrys spp. in 200 houses with water incursions in Houston, Texas
Genome-wide comparison of phage M13-infected vs. uninfected Escherichia coliPolarity within pM and pE promoted phage lambda cI-rexA-rexB transcription and its suppression
Antimicrobial susceptibility of lactic acid bacteria isolated from a cheese environment
Characterization and regulation of new secondary metabolites from Aspergillus ochraceus M18 obtained by UV mutagenesis
Overexpression of the ftsZ gene from Corynebacterium glutamicum (Brevibacterium lactofermentum) in Escherichia coli
Influence of carbon source and surface hydrophobicity on the aggregation of the yeast Kluyveromyces bulgaricus
Isolation and PCR amplification of a species-specific oxidoreductase-coding gene region in Listeria grayi
The presence of novel 3-hydroxy oxylipins on surfaces of hat-shaped ascospores of Ascoidea africana
AVOID FAULTY REASONING
Cause and Effect-Fire trucks
Linked Variables-Cold weather causes the flu
Anecdotal Evidence-Toads cause warts
AVOID FAULTY REASONING
After training the flea for many months, the biologist was able to get a response to certain commands, such as jump. The professor would shout “jump”, and the flea would leap
into the air .
Before publishing, the professor decided to take his experiments one step further. He sought to determine the location of the receptor organ involved. He removed one leg and the flea continued to jump on command, but as
each successive leg was removed, its jumps became less spectacular. Finally, with the removal of its last leg, the flea
remained motionless.
The professor decided that at last he could publish his findings. He set pen to paper and his conclusion was one intended to startle the scientific world: When the legs of a
flea are removed, the flea can no longer hear.”