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

Find out the concentration of sucrose solution that is equivalent to the osmotic potential of Potato tuber cells.

Extracts from this document...

Introduction

Osmosis Investigation By Christopher Stylianou Aim The aim is to find out the concentration of sucrose solution that is equivalent to the osmotic potential of Potato tuber cells. Factors All the independent variables, which could affect the investigation of Osmosis, are: > Mass- By changing the size of the cell could change the amount Osmosis occurring. > Concentration of Solution- By changing the concentration of the solution surrounding the cell could change the amount of Osmosis occurring. > Temperature- By changing the temperature of the solution or cell could change the amount of Osmosis occurring. > Size- By changing the surface area of the cell could change the amount of Osmosis occurring. Investigation I have decided with the research I have below to investigate the Concentration of the Sucrose Solution independent variable. This is because I can use a scale of 10 different solutions. E.g.: - 1 Molar of Sucrose Solution to Water or 0 Molar of Sucrose Solution to Water. Then I can work out how much each cell has gained or lost by weighing them and then see which is the nearest Potato tuber cell not to change it's concentration from the beginning will be the right concentration of sucrose solution to equal the concentration inside the Potato tuber cell. ...read more.

Middle

Water (cm�) 1 Molar 30 0 0.9 Molar 27 3 0.8 Molar 24 6 0.7 Molar 21 9 0.6 Molar 18 12 0.5 Molar 15 15 0.4 Molar 12 18 0.3 Molar 9 21 0.2 Molar 6 24 0.1 Molar 3 27 0 Molar 0 30 Mix the solutions using a glass rod. Then take 11 of the potato tuber cells (potato cubes) and place 1 into each beaker. Then set the timer on and leave for 24 hours. Repeat this again to get two sets of results. After 24 hours, take each potato tuber cells out of their beakers and wipe off any excess solution. Then weigh each cell again and record this into your results. Then work out how much weight the cell has gained or lost in each solution by subtracting the starting weight by the finishing weight. Fair Test: - To make it a fair test you must carry out these precautions: - * The measuring and the Sucrose and Water are accurate by using a measuring cylinder. * Don't use the same measuring cylinder for the Sucrose and the Water because it might contaminate the solutions and make it an un-accurate and un-fair test. * Make sure that each potato tuber cell is 1cm� and doesn't have excess liquids on them. ...read more.

Conclusion

Also, the temperature, mass or/and surface area of the potato tuber cell could have changed which would affect the results. I think my method is good because you can get accurate results by using simple apparatus and knowledge. But it could improve my method by controlling the other factors better by making sure that the potato didn't have any kind of excess liquids on it, the mass was the same weight every time and the surface area was the same size every time. I could only do this with special equipment that wasn't provided for this experiment. Also, if we put the experiment in a controlled temperature environment, this wouldn't affect the results either. I had preliminary work to help me with the investigation, which was very useful in making my prediction. But now I have done the experiment, I could concentrate around the 0.3 - 0.4 Molar Sucrose Solution and go up in hundredths instead of tenths to get a more precise result. I could do another experiment which the same method but instead of using sucrose, I could use a different mineral to see if it will affect the results in anyway. E.g.: - Starch. I got my research from the Biology GCSE textbook and from the Internet- http://www.purchon.com/biology/osmosis.htm ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Exchange, Transport & Reproduction 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 AS and A Level Exchange, Transport & Reproduction essays

  1. Marked by a teacher

    Investigate the water potential of celeriac.

    5 star(s)

    Volume of 1.00 mol dm-3 sucrose solution (ml) Volume of water (ml) Test tube 1 0.0 10.0 Test tube 2 2.5 7.5 Test tube 3 5.0 5.0 Test tube 4 7.5 2.5 Test tube 5 10.0 0.0 Use the cork borer, cut 5 cylindrical pieces of celeriac from a single piece of celeriac.

  2. Marked by a teacher

    Osmosis. Aim: To find the molarity of potato tubers cell sap. BIOLOGICAL ...

    4 star(s)

    of molecules that can pass at one go, as more area of the semi-permeable membrane is exposed to the solution. So, when the surface area is less, the rate of osmosis decreases because only a few can pass at one time.

  1. Marked by a teacher

    Determining the Water Potential of Sweet Potato Tissue

    4 star(s)

    200ml = 1 mole using this calculation the molarity was worked out. Percentage change is worked out using the formula: Weight after - Weight before Weight before Variables These factors must not be changed and are the fixed variables of this experiment.

  2. Water Potential of Potato Tuber Cells: The Density Method

    Rise - remains close to solution surface. Rise - slower than before. Rise - much slower. Rise - very very slowly. None - drop remains at the bottom. Fall - slowly. Conclusion As the concentration of the solution increased, the speed of the drop rising decreased until eventually at 0.5 mol dm-3 it remained in the same place and the fell at 1 mol dm-3.

  1. Osmosis in Potato cells

    From these results I can say that the experiment was an accurate and fair one and my results prove that osmosis has taken place by water moving from the cell to the solution. When looking at the percentage change in length table and graph, it can be seen that there

  2. To find out the factors affecting the refractive index of liquid by using different ...

    There are two important right angle triangles involved in determining the refractive index. This is illustrated by the diagram below. Use the following formula to measure the refractive index. Pilot test The main purpose of the pilot test is to find out whether this plan is reliable and whether the apparatus can give out appropriate results.

  1. Investigation on Osmosis using a potato.

    It will be a lot harder for me to predict the ones I am about to take on because in the final experiment there is going to be a large range solutions therefore making it difficult to predict exactly. Although these are not all of the molar solutions they are the basic ones and will be used to compare.

  2. Investigating osmosis on swede cells.

    A solution that contains more solute particles than another, and hence has a low water potential, is referred to as being hypertonic, whilst the less concentrated solution is hypotonic. Simpkins. J, William, J.I, Advanced Biology, Collins Educational, 1990 A diagram to show a plant cell in full turgidity and total plasmolysis.

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