invetigativedesign.html

Danger
in the Produce Aisle

Investigative Design

Materials

Eight large Petri dishes	45 apples
Two small Petri dishes	One electronic pipette
Ten volumetric flasks	Fluoroscein dye
Spectrofluorophotometer	Rhodamine dye
50 small vials	One volumetric pipette
Distilled water	Ivory Dish Soap
Organic Fruit Wash	Vinegar (5% acid)
Five containers with lids	Watch with second hand
Manual pipette	Black permanent marker

Investigative Design

The manipulated variable is the washes used on the apples, such as vinegar and water and soap and water, and the responding variable is the amount of dye in the rinse. Control variables are the types and brand of fruit, the amount of dye applied, the lab equipment and the types of dyes, which were Rhodamine and Fluorescein.