• 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
  • Level: GCSE
  • Subject: Science
  • Document length: 2224 words

What effect different solutions, with the same water potential, have on potato and cucumber strips (by mass).

Extracts from this document...

Introduction

Jessica Rossi What effect different solutions, with the same water potential, have on potato and cucumber strips (by mass). Plan Introduction Plants in the soil have their roots in a dilute solution of various mineral ions. Sometimes, the soil they are planted in gets flooded with sea water (which has an average of 0.3 sodium chloride concentration). In these cases the roots are observed to wilt and become flaccid. In my experiment, I will simulate this situation using potato and cucumber strips, placing them in different solutions (sodium chloride, glucose and sucrose) at different molar concentrations. A substance dissolved in water is called a solute. A solvent is a liquid that is able to dissolve another substance, a solute, to form a solution. Water potential is a measure of the ability of a solution to give out water. Water potential (y) can be expressed as the sum of the solute potential (ys) and the pressure potential (yp). (y) = (ys) + (yp) The water potential of pure water is zero and all other solutions have a negative water potential. The greater the solute concentration, the more negative is the value for water potential. Background Information The water content of plants depends on environmental conditions. In land plants, water plays a vital role in structural support and mineral transport, thus, the lack of water may lead to wilting or possibly death. ...read more.

Middle

[image006.jpg] * Place the correct quantity of pure distilled water into a beaker, measured using a different measuring cylinder. * Place all test tubes in test tube rack. * Place 20cm of each solution into each of the test tubes, so that all 30 test tubes will be holding each a different concentration of any solution. * Place 20cm of distilled water in another two test tubes, these will be used as the control in order for the test to be fair. * Cut 16 potato cores and 16 cucumber cores and place them on a ceramic tile. Using a scalpel and ruler (calibrated in millimeters) cut the cores at 50mm, taking care that no peel is left and that all the cores are accurately cut at the nearest millimeter. * The cores will be individually weighed on a top pan balance to an accuracy of 0.01grams. * Each of the cores will then be placed into one of the 32 test tubes for 2 hours, timing kept by a stopwatch. * After 15 hours the cores will be removed from the solutions, blot-dried on top of a filter paper, and weighed straight away. * After the experiment has been completed, all apparatus has to be washed and properly placed away, and all organic material should be disposed of. ...read more.

Conclusion

However, this was impossible to do as 48 plant tissue samples were needed for each vegetable. * A variety of other similar plant roots could have been placed through the same procedure in order for comparison of different tissues. * A larger cucumber should have been used, in order to cut the chips out of the same tissue, and trying to exclude the seeds and placenta, as this could have lead to inaccuracy in the experiment. [image008.jpg] * Some results could have been inaccurate due to not allowing excess solution on the external surface of the cores from draining away before placing it onto the top pan balance. This superficial water would be measured as extra mass by the sensitive weighing scales, even if the cores have been blot-dried on filter paper beforehand. * Once the cells have been plasmolysed, it is possible that some of the solution has entered the cell between the cell wall and the cell membrane, given that the cell wall is fully permeable. This could lead to inaccuracy of results, as part of the mass in the plasmolysed plant cores would be caused by this intake of water, which has not been caused by osmosis. [image010.jpg] * The experiment was also lmited by the accuracy of the top pan balance, which showed mass in grams to one decimal place. ...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. The effect that different concentrations of salt solution in the water has on strips ...

    But because there are more on one side than the other, there's a steady net flow into the region with fewer water molecules, i.e. into the stronger solution (of salt). This causes the salt rich region to fill up with water.

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

    Lower water concentration so water moves out However even though I predict that there will be a loss of mass, I also predict that the loss will only be a little since the cylinder is almost at equilibrium. This means that I predict that the rate of water entering the

  1. Experiment to Compare Stomata Density in Different Dicotyledonous

    I found that through using a cover slip I got increased visibility and more defined stomata as they were thinner than the glass slides and cleaner too. I also developed a method to remove a large section of a epidermis peel from the leaf cleanly and with out taking parts

  2. The effects of organic effluent from the seweage on the biodiversty in a freshwater ...

    14. Temperature probes will be used to determine the temperature difference between the sites and hence determining the biodiversty.Sun is the main source of light for an ecosystem and hence the main source of heat. High heat capacity of water effectively buffers the temperature changes in aquatic habitats.

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

    Also, I must make the surface area available the same. Each of the potato chips will be cut 3cm by 1cm by 1cm. 2. After weighing the potato chips I will place them into 5 different test tubes. Now I must make the solutions of distilled water and sucrose concentration.

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

    results on a graph can measure the water potential of a tissue. Some water potentials would cause the mass or volume of the potato tissue to increase as it takes in the water molecules through osmosis and some of the water potentials will cause the potato tissue to loose mass

  1. An investigation into the effects of different concentrations of lead chloride on the growth ...

    The aim of the preliminary work was to find out: 1. Which medium cress seeds grow best in. 2. The method in which to distribute the cress seed, on the most effective medium, to obtain maximum growth. 3. The range of concentrations of lead chloride to use in the experiment,

  2. Osmosis investigation. My prediction is that as the concentration of the solute increases, ...

    I will take the potato lay it on the tile and bore downwards with the tool. Once I have 5 separate cylinders of potato I will roll them on the paper towel to soak the excess moisture. Thereafter I will weigh them and cut them down till they are 1.00 gram each.

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