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Water Potential And Potato's Coursework HELP!!!

hiya, im new to this forum so hi to all

i need some help on this coursework. i havent started the plan yet so can someone please send me their coursework, i wont copy it or owt i just want to have a look at it and hope that it helps me figure it out.

im doin aqa biology b as level and the cws titled:

determination of the water potential of potato tuber cells

i dont want no one telling me to pay this much and goto this site. can someone please either give me a free source of info or a copy of theirs.

and i am sorry if this is not allowed to be posted here.

regards
Reply 1
right, ive just found out abit more.

i have to find the concentration of the sucrose where the solution will be isotonic to the potato.

i did some research and found that the molarity of the sucrose solution will be around 0.4 to be isotonic so im going to use 0.2-0.6 molarity's in my experiment.

has anyone done this experiment before and can someone please give me some tips or something

sorry for posting in the wrong section too

regards

yus786
Reply 2
I'm sure I've done something like this before.
If you have to find the conc of sucrose at which it is isotonic with the potato you do it like this;

Cut equal sizes of potato pieces and weigh them. Put each one in a different conc of sucrose solution (0.1, 0.2, 0.3, 0.4, 0.5, 0.6). Leave them for a while.
Take the potato out and reweigh.
If there has been an increase in weight then the solution is hyptonic to the potato cells, if there has been a decrease then the solution is hypertonic.
The potato in the solution which is isotonic will not have gained or lost weight so the potato in the 0.4. solution shouldn't have any weight change.

Hope that's what you were looking for.
Reply 3
thanks for your help mate, by any chance have you still got the coursework??

or arent i allowed to ask for it?!

thats cleared a few things up though, i read up on it and i found that 0.4 is probably the solution thats isotonic. i will probably carry out your procedure in weighing the potato.

another question:

if i cut the potatos into smaller pieces will this be better for my experiment and why??

regards
Do it yourself! People can only help.
Reply 5
My God...this experiment...I can still remember it's the most basic experiment....
and Legend Killer is right...u must do it yourself...
and if you have doubt, you can think by yourself...like theorically is that so...
then utry to put the answer here...so they can guide you...