Biology coursework help

ExplosiveFly

could anyone please tell me what shape the graph should be? I got a graph tht starts to slope down then goes back up again (with concentration on the x axis and the mass on the y axis). If my graph is correct why does the graph go back up again at the end?

Hey if i had more info to help u with this...wots the experiment on?

Reply 2

OP

thats a good point... osmosis in potatoes

Reply 3

OP

well, we put the potatoes into solutions with different concentrations to see how osmosis changes the mass of the potato...

Reply 4

ExplosiveFly

well, we put the potatoes into solutions with different concentrations to see how osmosis changes the mass of the potato...

i did this one actually for my gcse...let me just check how my graph went!

Reply 5

Tazzie

i did this one actually for my gcse...let me just check how my graph went!

my graph went down all the way!...i dont know why your graph went back up...what concentrations did u do?

Reply 6

ExplosiveFly

could anyone please tell me what shape the graph should be? I got a graph tht starts to slope down then goes back up again (with concentration on the x axis and the mass on the y axis). If my graph is correct why does the graph go back up again at the end?

i reckon the graph could do that

because when the concentration inside the solution is low, water will move out of the cell and into the solution, due to osmosis thereofre decreasing the mass.
and as the concentration of the solution increases, water will move into the cell due to osmosis increasing the mass...so yes ure graph is right!

Reply 7

GH

Not supposed to go back up.

Reply 8

OP

2776

Not supposed to go back up.

hmm... i'm confused - so is my graph wrong or right

Reply 9

material breach

12

at low concentrations the concentration outside will lower than inside so water will flow out from the potato reducing the mass. When the conc. outside = conc. inside the mass of the potato will be equal to the mass of the potato out of the water. then as the conc outside increases the mass increases as water will flow in from outside. however it will stop at at point since the potato will become saturated.
this means the shape of the curve will be.......(thinks about it as has little knowledge of bio).....strange.

Reply 10

GH

ExplosiveFly

hmm... i'm confused - so is my graph wrong or right

Its wrong. Its supposed to go tangential at best.

Reply 11

OP

oh ok, an anomalie then? thanks very much - hey do you think i shud make up a result?

Reply 12

Lucy

ExplosiveFly

oh ok, an anomalie then? thanks very much - hey do you think i shud make up a result?

If the anomaly is way off then try and make it look less prominent. If you are drawing a line of best fit then make the gradient less steep or something. Do you know why this anomaly occured? Manual incompetence is not a good/acceptable reason. If you otherwise have 'perfect' results (which I doubt) then keep the anomaly because you have to write about inaccuracies/amendments in your evaluation. Nevertheless, either way, to gain a mark you must state whether you have any anomalous results.

Reply 13