The investigation I will be working on is does osmosis affect the weight of potatoes cells?

For this investigation I will be using

* Different levels of sugar solution e.g. 5% sugar 10%,15%,20% up to 30% , I will use these solutions to see the effects of stronger solutions has on the potatoes cells

* Potatoes (in thin slices), I will use these to see the effects of sugar solution on them.

* Scales, to measure the difference of weight on the potatoes after osmosis

* Stop watch, to measure the time the potatoes were kept in the solution and telling us when to remove them from the solution so the results were fairer

* Test tubes, to hold the liquid solution and the potatoes to stop them flowing over the table and making a mess.

Method

. Cut the potatoes into slices 1cm long using a knife.

2. Label test tubes and fill with ONE sugar solution.

3. Weigh the potato slices and record them on a table.

4. Insert the potatoes into the test tubes and use stop watch to record time.

5. wait 15 minutes then remove the potatoes and record their new weights

6. Repeat with different solutions

Prediction

I predict that on 30 percent of sugar solution the weight of the potatoes will increase but on the other solutions they will decrease.

I believe this because this solution has the highest sugar concentration. Therefore osmosis will have to transfer the sugar into the potato cells to even out the difference in concentration.

Planning to collect good data

Our group made the investigation fair because we used 5 potatoes on each concentration meaning we would have many results giving us a better average and a better result. We repeated the whole test using all the concentrations twice as this gave us two averages making sure our original was not corrupt. The concentrations we used were 5% sugar 10%, 15%, 20% and 30%.

In order to keep the test fair and accurate we used the same size potatoes and using a stopwatch to keep the emersion time constant in all the tests. The accuracy of the equipment was down to the condition of the scales and stopwatch when they were under our use.

Results shown in grams

Before Solution

5%

Before 10%

0%

Before

5%

5%

Before

20%

20%

Before

30%

30%

2.17

2.16

.78

.71

.97

.86

.89

.76

2.07

2.01

2.17

2.13

.91

.86

2.11

2.02

.81

.99

.92

.89

2.29

2.13

.88

.86

2.03

.95

.79

.87

.80

.79

2.51

2.40

.68

.65

2.01

.97

.74

.97

.92

.97

2.22

2.19

.89

.86

.98

.87

.87

.76

2.15

2.15

average

2.202

.788

.934

.87

.962

Conclusion

The charts average is showing me that the lowest concentration of sugar water has the highest average, it also shows it also has the highest recorded weight afterwards and its lowest weighted potato slices is near the same as the 30%s highest weighted potato slice. The trend I'm seeing is that the lowest sugar solution showed the greatest mass improvement but the 10% for some reason showed the least improvement and in a few of the potato slices actually decreased in their weight, this could be the answer to fast weight loss...then again maybe not.

This conclusion could be used to benefit medical science by explaining to us that if the right amount of salt is in someone blood then the cells will over absorb and release too much water making them shrivel and die , causing the test subject to die too, which would be unfortunate and quite nasty. We could also learn about why our bodies have diabetes and possibly learn to use reverse osmosis in our favour, for example using it to remove too much salt from someone who has eaten too much or to save someone's life that has overdosed on drugs and need to remove the drug from the cells in their body.

Evaluation

I feel that these result may not have been the most accurate, I predicted that the 30% solution would have been the more effective at increasing the weight of the potato slices and I still believe it would do so after this test. My theory was that because the sugar in the solution was higher than other the potatoes cells would take in more sugar because of its lower concentration. Anomalous results may have occurred because of defective cells in the potato, for example cells that have already died cannot absorb sugar as they are immobile.

As I said earlier I don't think my result were terribly accurate so in order to back up my prediction I could re-do the test, but this time take two sets of results in case the first or second result are incorrect which could have been the possibility with this test. As I'm not sure if I do have enough correct data I cannot yet give a certain conclusion and anything said could be incorrect. I don't believe that the equipment used, apart from the potato and the solution, could have changed the final results because they have no real purpose, apart from containing, timing and weighing which they all seemed good at doing. The method used I feel was fine, I could have used a better environment though, one that didn't involve me moving too much to reach the electronic scales or the test tubes etc.