Lab 2: The Scientific Method

Point of Today’s Lab

• In a real job, in real science, you will not have a lab manual with a cookbook recipe of steps for you follow

• Scientists get paid to figure things out….not do experiments they already KNOW the answer to

• A lot of being a scientist….is sitting in confusion

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Experimentation

• It’s how we learn important things about the world

• Good experimentation: baby monkey• Poor experimentation: kitten• Observation: you

Movies

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You play the “Scientist” everyday

• You stumble out of your room at 4 a.m. and turn on a lamp

• Nothing happens• Now what? Curse the darkness?

How has this been used?

• John Snow– London Cholera Outbreak in 1854– Thought it was spread by fog and mist– Discovered it was from a contaminated water

pump

John Snow’s Map

The Road to DNA Discovery

• Erwin Chargaff• Data displays that organisms have roughly

equal amounts of DNA base pairs• Real structure later discovered by James

Watson and Francis Crick….Rosalyn Franklin?

Chargaff’s data

%A %T %G %C

Mycobacterium 15.1 14.6 34.9 35.4

Yeast 31.3 32.9 18.7 17.1

Wheat 27.3 27.1 22.7 22.8

Sea Urchin 32.8 32.1 17.7 17.3

Marine Crab 47.3 47.3 2.7 2.7

Turtle 29.7 27.9 22 21.3

Rat 28.6 28.4 21.4 21.5

Human 30.9 29.4 19.9 19.8

Chargaff

• Maybe Chargaff didn’t discover the structure of DNA….but he contributed a VERY IMPORTANT OBSERVATION that lead to the discovery. Sometimes we don’t always get a conclusion. That’s okay. His observations many scientists later

Unknown Liquids

• Mix samples and deduce something about their relationship

• 3 mL in each tube • You have indicators A & B, you also have

substances 1-6– Addition of 5 drops should be enough for change

• KEEP TRACK OF WHAT YOU ADD TO WHAT

Pattern Master

• Bio 181L Go Folder Pattern Master– Pattern Master for Fun- Select Demo

• Find a pattern relating to shapes, colors, numbers, letters, etc.

• Put cards in correct order to make them all “happy” or green

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Rule Quest

*NEIGHBOR definitions are clockwise, counterclockwise

Given 1-step clockwise*, it could be...

• Perimeter to top inner color

• Top inner color to lower left color

• Lower right color to lower left color

Homework

• Quantum Mine (BONUS)• Logic of Disproof Assessor• Pattern Master (Individual)• Easy= 45 Points, Medium= 50, Hard= 55– 50 for written portion (follow rubric)

• Written explanation of unknown liquids (Group)– Rubric and example on lab calendar

Quantum Mine

• Bio 181L Go Folder Quantum Mine– Don’t Log in- click “New Mine”

• Shoot light beams, find out where gems are

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Rules of the Mine

http://en.wikipedia.org/wiki/Black_Box_(game)

or...