biology osmosis question

hi, i have a question regarding biology
say you do an experiment like stated in a book, and say you weigh a plant sample, put it into a sucrose solution, and weigh it after to measure the change in weight
what if that plant cell BECAME plasmolysed,
so the cells in the plant lost WATER , so the cell membrane MOVED OUT.
and it became PLASMOLYSED
what would you have between the cell wall and membrane?
what would/ how would this affect your results
tyvm, looking foward to replies

PS ALSO : how would you represent this all on a graph? what would you use to represent the differnet things?
how do you represent perentage change in mass on a LINE graph?
tyvm!

Reply 1

jonathan3909

Original post by sixthformer

I could help if only you could explain the question much more clearly :smile:

Reply 2

sixthformer

Original post by jonathan3909

I could help if only you could explain the question much more clearly :smile:

Say you had 5 plant strips of equal mas
and you put them into FIVE different sucrose concentrated solutions
and measured the change in mass before, and after.
say you had:

percentage change in mass of 0.00 mol dm^3 = 10%
the next conc = 7%
then 0%
then -2%
then -3%

how would you plot the results
on a graph?
could you draw me one ?
:smile:

Reply 3

Pharm Boy

Original post by sixthformer

I don't really understand either.
But if the question is what kind of graph to plot the data on.. I'd suggest a bar chart..
EDIT: with the concentration as your x-axis and the mass of plant as your y. the negitive values would be plotted below the x-axis.
sorry I didn't read it properly first time :tongue:

(edited 13 years ago)

Reply 4

butterflyeffect1

Original post by sixthformer

What I would do,

The concentration of sucrose is your independent variable, so this usually goes on the X axis. Then (obviously by elimination!) put the % change in mass as your Y axis title. I would plot it as a scatter graph (as percentage change is continuous data... bar graphs are usually used for categoric data) And if is there is a trend, draw a free-hand curve (don't join each point with a ruler! and that relationship doesn't seem linear so I wouldn't use a straight line either.

Reply 5

int_applicant

Original post by sixthformer

I wish I understood your question.......

But when a plant cell is plasmolysed you have the external solution between the cell wall and the protoplast....so in your case it will be the sucrose solution.

Reply 6

sixthformer

Original post by Daniel-Ballingall

would you draw a line or curve, and when do you know when to do what?ty

Reply 7

sixthformer

Original post by butterflyeffect1

say you had two y axises, above is positive change, and below is negative
and the points went downwards
how do i know wether or not to use a curve , or a line
tyvm +1

Reply 8

butterflyeffect1

Original post by sixthformer

say you had two y axises, above is positive change, and below is negative
and the points went downwards
how do i know wether or not to use a curve , or a line
tyvm +1

Those axes sound good. There is no definite rule, judge which would represent the relationship best. Do not try to force a straight line for the sake of it if a lot of the points would be quite far from it. If the data you said earlier is what you have measured the relationship doesn't sound linear so I wouldn't use a straight line.