• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Investigate the use of Osmosis in potatoes

Extracts from this document...

Introduction

Investigate the use of Osmosis in potatoes Aim: I will investigate how osmosis occurs and the effect of osmosis and the diffusion of salt to water and how the rate of osmosis changes. I will want to check the independent variables and independent variables and finally I will need to check the mass of the potato before and after the experiment. Equipment needed: 2/3 potatoes, cork borer, ruler, beaker, thermometer, potato cuttings, scales/TBP, measuring cylinder, pure water, timer, and a calculator. Prediction: I predict that the potato will take in more water when put in a high concentration of water. I think this because the theory of osmosis states that water will pass from a dilute solution i.e. a high concentration of water, to a more concentrated solution i.e. a low concentration of water through a partially permeable membrane. A partially permeable membrane is a cell membrane that only allows some molecules that are small enough to fit through the tiny holes e.g. water, through. It therefore prevents the passing through of molecules that are too big e.g. sucrose. The water can pass through the cell membrane in both directions but is likely to balance the amount of water in the container with the amount in the potato cell. ...read more.

Middle

* Group them into 6pairs and weigh each pair noting the average mass down to 2 decimal points. * Put each pair in separate containers. * Measure out 6cm3 of 0.0molar glucose concentration i.e. water and pour it into a container with a pair of cuttings, ensuring that the cuttings are completely covered by the solution. * Label the container with the amount of glucose concentration. * Then measure out 6cm3 of 0.2m of glucose concentration and put it in a container with a pair of potato cutting and label it. * Do the same for 0.4m, 0.6m, 0.8m, and 1.0m. * Leave the containers for 24 hours and then re-measure the size and mass of each potato cutting, noting the average of each pair to see if they have changed. * Measure how much liquid is left in the containers. * Repeat the whole experiment 3 times to ensure that it is a fair test and to ensure that accurate averages will be used in the graphs. Preliminary Experiment Concentration of Sucrose Vol. cm3 Average mass of cutting before experiment (g) Average length of cutting before experiment Average mass after experiment (g) ...read more.

Conclusion

I could have measured more accurately by having a larger scale on my measuring cylinders. Also, I could have found a way of drying the potatoes without losing too much of the solution, so that there would be an accurate amount of liquid remaining in the container after the experiment. I could have done more experiments in order to have a more precise average plotted on my graph. I could also have timed the experiment more accurately since each of the repeats may not have been exactly 24hours. Using two potato cuttings in each container was slightly inefficient as they weren't identical causing inaccuracies. The containers were moved around. This may have affected the rate at which the water diffused in and out of the cells and may have affected any evaporation. The movement of the containers could also have changed the environmental conditions causing inaccuracies. All these factors may have affected the quality of my results and could be improved on. So, although the results were fairly accurate, there were more considerations that should have been thought of to add to the result's reliability. Therefore my conclusion is that there is sufficient evidence to say that the results show correct osmosis in action yet, the results seen by osmosis could have been more accurate ...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 Green Plants as Organisms section.

Found what you're looking for?

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

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 Green Plants as Organisms essays

  1. Peer reviewed

    Osmosis in potato and apple

    3 star(s)

    The hypothesis is that there is a different in water potential between apple and potato tissue. I have done some background research on osmosis and related topics. The sources of the research are: 'A-level Biology' (page 214) by W.D. Phillips And T.J.

  2. Determine the water potential of potato tuber cell with the varying affect of solute ...

    As explained above, because water molecules move down the concentration gradient, it will mean a net movement of water will be going out of the cell. This basically happens because the concentration of water outside the cell is less than on the inside.

  1. Free essay

    Investigation osmosis in potato cells

    I can prove this because its in my results table showing average change in mass. The graph is evidence to backup my prediction showing it was correct. I also said that if the concentration of sugar in the water is high, the potato will then have a higher water potential

  2. What effect does the sucrose concentration have on osmosis?

    There are three rows to write in because three experiments were conducted for each concentration. The % Sucrose column is there to show how much of the solution was sucrose and the % water column is there to show how much of the solution was water.

  1. Investigate and find the water potential of baking potatoes and sweet potatoes in (N/mm2) ...

    It's hydrophobic/hydrophilic nature makes it theoretically impermeable to water molecules. So how does water get into a cell to affect its water potential? It is generally accepted that the cell membrane is a "fluid mosaic", that is the lipid molecules are free to orient as they like.

  2. Water moves from a high concentration gradient of water to a low concentration of ...

    The impermeable membrane controls what goes in and out. The impermeable membrane has tiny holes letting water to get through and other small substances. Concentration of sucrose solution (M) Prediction Analysis 0 There is no sucrose in the distilled water therefore water will go in rapidly to the potato by

  1. An investigation into the effect of differing water potentials on the mass or volume ...

    There would be no change in the mass or volume of the cells due to the balancing of the flow of water molecules in and out of the cells. The diagram below shows this. (Pictures referenced from www.koning.ecsu.ctstateu.edu/plants_human/osmosis.gif) Testing the tissue in solutions with different water potentials, and plotting the

  2. The factors affecting the rate of permeability in a cell membrane?

    The preliminary can also help decide how much water to use as too much water can dilute the colour of the beetroot too much and using too little water could leave too dark colour so the preliminary experiment should help decide how much water to use, I predict that 10cm� should be suitable amount.

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