Science uncertainty -exists because scientist can’t investigate things that can’t be seen.

Hypothesis - possible explanation for event or set of observations.

Changing science – mid – 1970’s technique for altering genes developed.

Collaboration - scientists work in teams.

Observing and questioning - can only study things that are seen.

Observations - made directly with senses and indirectly with instruments to extend senses.

Test hypothesis - carefully designed experiment.

Variable - factor that can influence experiment.

Experiment - designed to investigate effects of one variable.

Experiment parts - control setup and experiment setup.

Prediction - uses form of If…then statement.

Sources for science - interviews, college and public libraries, experiments.

Microscope - instrument that enlarges the image of specimen.

Resolution - ability to see 2 points separately; sharper the image, better resolution.

0.1mm - resolving power of unaided human eye.

Light microscope - magnify images of 1500 times.

Electron microscope - uses electrons instead of light; 1000 times better than light microscope.

   Field studies – studies that take place in organisms natural environment.

Electrophoresis – molecules separated by shape, size and electrical charge.

Cell Fractionation – study with large,pure samples of various organelles.

Centrifuge – tool that separates mixtures by spinning them at various speeds.

 Chromatography – technique to separate mixtures of liquid or gas

Tissue culture – technique used to grow large amounts of a single kind of cell. It decreases the need for animal experiments.