Experiment Design

[ckstubbs]

I am back in college after more than 10 years, to get a degree in Biology. The lecturer gave us this as a lab assignment. My hypothesis after 2 hours was shot down as it looked at 2 variables at once. Can anyone point me in the right direction?

 

Design an experiment to determine the relationship of water properties & fish abundance (globally).

Give: 1. Hypothesis

2. 3-5 predictions, &

3. propose a way to come up with a collection of data.

 

 

Water properties - salinity

- oxygenation

- temperature

{- pH} possibly

 

I just need some help for old 'dummies', like those books. I have plopped myself in the thick of things, I can barely remember anything.

 

Thanks ya'll

 

 

[Horza2002]

Basically, you need to take each of the variable and alter them seperatly while keeping the other the same. Temperature is the easiest example; make up a lot of whatever solution your going to use (this will keep oxygen concetration, salinity and pH all constant), seperate them out into several different flask and then have each flask at a different temperature.

 

Then you just do the same for each of the variants you want to test. All you need to remember is change one variable at a time and change it to a range of values aswell (i.e. to an experiment at 10, 15, 20, 25, 30, 35, 40oC etc.)