• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  7. 7
    7
  8. 8
    8
  9. 9
    9
  10. 10
    10
  11. 11
    11
  12. 12
    12
  13. 13
    13
  14. 14
    14

An experiment to show osmosis in potato chips in different concentrations of sucrose solution - also investigating how potato chips change in volume and weight when placed in different concentrations of sucrose solution

Extracts from this document...

Introduction

Factors affecting osmosis in potato tissue Introduction: I am going to design and modify an experiment used to show osmosis in potato chips in different concentrations of sucrose solution. I am also going to investigate on how potato chips change in volume and weight when placed in different concentrations of sucrose solution. I will also conduct a preliminary experiment before my final experiment. Aim: To investigate the effect of different concentration of sucrose solution on potato chips. Hypothesis: I would expect the potato chips to turn flaccid when they are placed in a strong sucrose solution because the water from within the cells will diffuse out leaving the potato flaccid. The potato chips left in the weak sucrose solutions should turn turgid in a weak sucrose solution, due to the water being absorbed by osmosis into the cells of the potatoes, this will make the potato chip larger in size. I should also be able to find some potato chips, which have neither increased nor decreased in size because the concentration in the potato is the same as the sucrose solution, so no mass or length would be gained or lost. Scientific knowledge: Osmosis is a type of diffusion, where the molecules move from an area of high concentration to an area of low concentration passing through a partially permeable membrane. When distilled water or a weak sucrose solution or a diluted sucrose solution is used, the water molecules will pass through the semi-permeable membrane into the potato. This is due to the fact that the water is more concentrated outside, so the molecules in the water will move through the permeable membrane, and in this experiment it will pass through into the potato. The potato chip will increase in length, and weight due to osmosis. When a strong sucrose solution or a concentrated sucrose solution is used, the water within the potato will move out of the potato through the semi-permeable membrane, and into the strong sugar solution, of which the potato is soaked in. ...read more.

Middle

Graphs: See graph paper. Evaluation: Studying the results I obtained I realized that having three different concentrations were not enough, and I could increase the amount to six different concentrations. I only placed two potato chips into each solution, there weren't enough results and so to increase the reliability I will also increase the amount to three potato chips to each beaker. The length was hard to measure accurately, and so if I were a millimetre out it would have made a large percentage difference. I also realized that that length was very hard to measure and was difficult to measure the length precisely and weight the mass of the chips in two minutes. I have decided to measure the volume of solution instead of the length for my actual experiment, because the volume of solution is a lot easier and quicker to measure and is also more accurate. I will also be changing the volume of solution to 100cm3 of water, because 120ml was hard to calculate the percentage and so using 100ml3 would be easier to work out the percentage. The results collected are rather poor. There aren't enough concentrations for me to plot a good graph. It is also very hard to plot the graph when one of the results is an anomaly, and because there are only three concentrations it is very hard to defy which one is the anomaly, and even whether there are any anomalous results plotted. Conclusion: I have made some changes to my method and will be using the new method for my actual experiment. Final Experiment Introduction: I have done my preliminary experiment and with the experience gained from the experiment I have re-written the method and apparatus list to fit my new method. My experiment should work better this time due to the numerous changes and improvements made. Aim: To investigate the effect of different concentration of sucrose solution on potato chips. ...read more.

Conclusion

I have realized that the volume of solution also increases as the concentration increases, and so when there is a low concentration the volume also decreases. Graphs: See graph papers Scientific explanation: The volume of water increase as the concentration becomes stronger, this is because the water in the potato chips' cells are in the area of high concentration and so the water moves out of the cells and into the solution. So when a weak solution is used the sucrose solution is more concentrated than the water within the potato cells, therefore the solution moves into the cells and so the volume of solution will decrease and the size of the potato chip increase. Evaluation: My results were better this time, but I still remain unsatisfied with the amount of results gathered. I think the experiment would of worked better if I could use more potato chips. Instead of only using three potato chips to a concentration I think I could of used five potato chips instead. When I did this experiment I was limited to half an hour to set up everything and so it was very rushed and I didn't have enough time to make my measurements accurate. Cutting the potato chips to all the same dimensions was very difficult because the dimensions are very small. The apparatus used was also very inaccurate, for instance instead of using a measuring cylinder I could have used a burette to make the reading more accurate. I increased the amount of concentrations from three to six but I still think six solutions are still very unreliable and that it should be ten or twenty different concentrations. When the experiment was conducted the temperature was not kept the same and this could increased or decreased the rate of which osmosis took place. Conclusion: Overall I think my experiment was relatively good, and if more modifications were made the experiment could have been better. My results were fair and I am pleased with the results. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Life Processes & Cells section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Here's what a teacher thought of this essay

3 star(s)

*** Overall a well planned and carried out experiment which needed more thought put into the discussion of results and the evaluation of the method.
Planning was well carried out with a trial experiment. The prediction could be made clearer. If the prediction could be made quantitative ( perhaps by doing some background research) this would be helpful
Obtaining results The student carried out and trial experiments and a good range of the independent variable with a fair number of repeats. The student should try to ensure all units and concentrations are clearly recorded. It would have been better to only use one method of recording the dependent variable. This would have allowed more time for repeating anomalous results.
Analysing Evidence and Evaluation The graph was not available to view. The student needed to explain the extent to which the conclusion supported the prediction and look at ways of improving the reliability of the evidence. The student should try to account for the anomalies mentioned.

Marked by teacher Stevie Fleming 01/01/1970

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Life Processes & Cells essays

  1. Marked by a teacher

    Biology Coursework - Osmosis

    5 star(s)

    I hope this preliminary test will make it easier for me to find accurate results in my full investigation and to predict the results I should expect. Preliminary: Variable & Controlled Variables Just as with the main investigation to conduct a fair test, I will need to choose the independent

  2. Marked by a teacher

    Potato / Osmosis Experiment.

    5 star(s)

    Calculate the percentage gain/loss and plot on a graph. Preliminary Results: Preliminary Results Graph: The preliminary experiment has also served to support and justify the prediction and theory of the experiment further. It has done this by displaying the negative correlation (between % gain/mass and sucrose concentration) that I expected there to be because of the reasons stated in my theory.

  1. Marked by a teacher

    An Experiment to determine Water Potential in Potato Tissue.

    4 star(s)

    This means that the more solute in a solution, then the water potential will be lower. Solute potential is the amount the solute molecule is lower then the water potential. Pressure potential is the amount of pressure that is applied on the plasma membrane by water diffusing into the cell,

  2. Marked by a teacher

    Experiment to find the effect of sucrose solution concentration on potato and apple tissue.

    4 star(s)

    tissue is placed in solution with the same X as the cells there is no net gain or loss in water from the cells and the tissue does not gain or lose mass. This is the point of equilibrium and can be used to calculate the average X of the

  1. Marked by a teacher

    Gcse Biology Assessment - Osmosis

    3 star(s)

    osmosis goes down, and after that point the rate increases as water moves faster and faster out of the potato cells, due to the increased concentration of sugar, and therefore the decreased concentration of water in the solution. GCSE BIOLOGY ASSESSMENT - OSMOSIS Evaluating Evidence The prediction that I made

  2. Marked by a teacher

    Find the rate of osmosis in different vegetables (Carrot, Potato, Swede, Parsnip and Sweet ...

    3 star(s)

    1 mass change (g) Exp. 2 mass change (g) Average mass change (g) Potato Swede Sweet Potato Carrot Parsnip Results table for percentage change: Vegetable Percentage change in Exp. 1 (%) Percentage change in Exp. 2 (%) Average percentage change (%) Potato Swede Sweet Potato Carrot Parsnip * I will put the results into bar and/or pie charts in my analysis.

  1. Peer reviewed

    To investigate the effect of different concentrations of sucrose solution on plant tissue/cells

    4 star(s)

    I am using a cork borer because it will give pieces the same and thickness. I am weighing the potato because I need to know its starting weight so I can work out the weight change. * I will fill the test tubes with: Test tube 1- 25ml of distilled

  2. Aim To determine the water potential of a potato tuber cell

    I tried to have consistent blotting, and so any error due to too much or too little blotting is likely to be minimal given that the error is quite likely to be consistent. The improvements I can put to my method, especially to the blotting error would benefit the experiment.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work