A control treatment is when the level of the factor is zero. Dependent Variable -As the investigator changes given independent variable, those factors that that depend on the independent variable will change. Thus the investigator measures the dependent variables in the attempt to understand the relationship of independent and dependent variables. Standardized Variables -Variables that may cause changes in the dependent variables but which the investigator attempts to keep equal across all treatments involving the independent variable. Replicates -The number of times one repeats a given experiment or part thereof.
Daphnia use their large second antennae to swim, resulting in jerky movements through the water.
This movement should be visible with the naked eye. These organisms are good for our research purposes and similar drug exposure experiments because their exoskeleton is completely transparent permitting observation of internal organs. A two-chambered heart can be seen with the microscope. Under low oxygen conditions, the blood is red due to the production of hemoglobin. You will be measuring the effect of drugs on the Daphnia heart rate by placing the crustaceans in water containing the drugs.