• 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

Investigation of the effect of differing concentrations of sucrose solution on potato.

Extracts from this document...

Introduction

Investigation of the effect of differing concentrations of sucrose solution on potato Background Knowledge Osmosis is the diffusion of water molecules from an area of high concentration of water molecules to an area of low concentration of water molecules through a selectively permeable membrane. Osmosis occurring across a selectively permeable membrane The molecules move down a concentration gradient Plant cells are surrounded by a cell wall. Osmosis acting on a plant cell when a cell is in a less concentrated solution occurs with the water molecules into the cell. Water diffuses into the cytoplasm and vacuole through the selectively permeable membrane causing the cell to swell and become burgid. Plant cell in a less concentrated solution In a concentrated solution when osmosis takes place water diffuses out of the cytoplasm and vacuole. First the cell shrinks a little and becomes flaccid. The membrane then pulls away from the cell wall and the cell is plasmolysed. Plant cell in a more concentrated solution Plan for Investigation I plan in this investigation to investigate the hypothesis that the higher the concentration of sucrose solution the potato will shrink, but in a less concentrated solution it will expand. ...read more.

Middle

Put 20 cm of 2M sucrose solution into two of the test tubes 6) Add a potato piece into each test tube and leave overnight 7) Repeat steps 2 to 6 four times using a different concentration of sucrose solution each time. Follow the table below to be able to make up the required solutions. 8) Remove the potato pieces and measure their final length and final mass and work out the percentage change in mass and length using the following two equations- Percentage change in length Final length - initial length = Change in length Change in length Initial mass X 100 Percentage change in mass Final mass - initial mass = Change in mass Change in mass Initial mass X 100 9) Record all your results unto a table and plot your results onto a graph Strategy for dealing with results I will record my results unto 3 tables like the 3 three below- I will plot two graphs using the following axes- Fair test To ensure a fair test and accurate results I will conduct two experiments for each different concentration and will calculate the average loss in weight and length. ...read more.

Conclusion

I can see from my graph and results that the hypothesis was proved correct and I can also see that my graphs follow the trend, which I predicted they would. The reason why my predictions and my hypothesis were proved correct is because of osmosis. Water molecules move from cell to cell by osmosis. Osmosis is when water molecules move from an area of high concentration of water molecules through a selectively permeable membrane to an area of low concentration of water molecules. The water molecules move down a concentration gradient. Plant cell in a less concentrated solution In a less concentrated solution the cell will swell, however in a more concentrated solution the opposite occurs. Plant cell in a more concentrated solution Evaluation My results support the firm conclusion that the potato shrinks in a higher concentrated solution but expands in a less concentrated solution. If I were to do the investigation again I would conduct three experiments for each concentration and calculate the average result. I would also take a range of concentrations between 0M and 2M at 0.25M intervals rather than at 0.5M intervals. Doing both these things would ensure that I would get even more accurate and precise 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 AS and A Level Molecules & Cells 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 Molecules & Cells essays

  1. Investigation of the effect of adding different concentrations of NaCl to an enzyme-substrate (amylase-starch) ...

    0.0 1.0 0.0 1.0 0.0 1.0 0.8 0.2 0.8 0.6 0.4 0.6 0.4 0.6 0.4 0.2 0.8 0.2 11. Place one respectively labelled syringe in each of the test tubes placed in the rack 12. Using a pipette and the iodine solution, add a drop of iodine in each of the spots in both spotting tiles.

  2. Experiment to investigate the water potential of potato tissues when immersed in various sucrose ...

    The following figure summarises the stages involved in the osmosis that occurs when potato tissues are immersed in solutions of different concentrations (varying water potentials): Figure 1: Summary of osmosis in a plant cell: Water potential (?) of external solution compared to cell solution: Higher water potential: Equal water potential:

  1. To find out how different concentrations of sucrose solution affect the incipient plasmolysis of ...

    Lids need to be placed on the McCartney bottles to prevent substances from entering the McCartney bottles and contamination from occurring also to prevent the solution from evaporating because this will affect the rate of osmosis as some of the solution is evaporating so there is less solution left

  2. Catalyse Investigation

    substrate increase; not all the collisions of the substrate will be successful because some active sites will be saturated (occupied by substrate/products). The frequency of this occurrence increases with the substrate concentration, and eventually the terms cancel out, leading to no rate increase with substrate concentration increase at high concentrations.

  1. Biology Osmosis Plan

    - Scales to measure the mass of the potato. - Knife to peel the bits of potato I did not want in the experiment. -Test tube rack to hold the test tubes whilst reacting. - Tile for the potatoes to lie on whilst measuring. Prediction I predicted that the more concentration of sucrose in the test tube, the mass after would be less than at the start.

  2. Investigating Osmosis.

    number of results are used, or a difference in the potato for those cylinders. Either of these would easily be recognised if a larger number of results were collected and used. Another result that appeared unusual was the 'step' in the graph for the sucrose solution between 0.25% and 1%

  1. Amylase Investigation

    In older names the suffix is added to the name of the substrate, as in amylase, an enzyme that breaks down the polysaccharide amylose. In newer names, the suffix is added to the type of reaction, as in lactase dehydrogenase, an enzyme that converts lactase to pyruvate by transferring a hydrogen atom to nicotinamide-adenine dinucleotide (NAD).

  2. Peroxide Investigation

    Competitive and Non-competitive Inhibition - Enzymes are not required to work at their optimum rate, i.e. a reaction may stop when sufficient product has been formed, and this is called end product inhibition. Another type of inhibitor is a non-competitive inhibitor, which binds to an enzyme at a place

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