ATAR Notes: Forum

VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Biology => Topic started by: dooodyo on February 23, 2011, 04:17:23 pm

Title: Dooodyo's question
Post by: dooodyo on February 23, 2011, 04:17:23 pm

Hey guys,

I was wondering what would be the control, if there even is one,
in an experiment in which potato cells were placed in differing
concentrations of sucrose and why?

P.S the experimental variables were 0% sucrose solution (distilled
water), 40% sucrose solution and 80% sucrose solution.

Title: Re: Dooodyo's question
Post by: Chromeo33 on February 23, 2011, 06:46:02 pm

If I learned anything from Psych, the control of any experiment is the condition in which the independent variable - in this case, the presence of sucrose - is totally absent from the (metaphorical) equation.

And so the control conditions of this experiment would be the potato cells placed in the solution of distilled water (i.e. 0% sucrose concentration).

Hope that helps? Someone could probs confirm this as it is Biology and not Psychology :)

Title: Re: Dooodyo's question
Post by: dooodyo on February 23, 2011, 06:55:25 pm

Oh haha thanks  :D

But do you happen to know why the
distilled water is the control?

Since the experiment was to observe
the changes in mass of potato cells due to
changing sucrose concentrations since,
the potato in the sucrose gained mass.  :P

Title: Re: Dooodyo's question
Post by: Russ on February 23, 2011, 06:57:07 pm

Not necessarily, depends on what your experiment is testing. If it's osmosis, changing the sucrose concentration (solute) outside the cell will affect the movement of water molecules - thus a 0% sucrose solution may not be ideal.

Best control would be no solution at all, just the potato cells.