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

investigate the effect of osmosis on pieces of potato in different concentrations of sucrose solution.

Extracts from this document...

Introduction

Biology Coursework - Year 11 Osmosis Investigation Planning Aim To investigate the effect of osmosis on pieces of potato in different concentrations of sucrose solution. Apparatus 6 Petri dishes Marker pen Beakers Stop clock Cutting tile Knife 25cm3 Measuring Cylinder Distilled water 1.0 Molar solution of sucrose Potatoes Tissue paper Mass balance Plan The factors that affect the volume of water taken in by the potato are: o The concentration of the sucrose solution that they are placed in o The size of the potato o The time the potato is left in the solution Before we started the experiment some preliminary work was done to establish the appropriate size of the potato pieces and the duration of time they were to be left in the solution. To ascertain the size of the potatoes we were to use various sizes of potato were put into the petri dish at different times, water was poured onto them until the piece investigated was completely covered. The size of the biggest piece of potato that was covered, but without the water overflowing the rim of the petri dish, was chosen to be the correct size. We found that 1cm x 3cm x 3cm was the best size. To determine the duration of time to leave the potato pieces in the solution we first placed a piece of potato in a solution of 0.5molar sucrose solution which was left for 10 minutes. ...read more.

Middle

The length of time the anyone potato piece is in the solution is 20 hours. 2) The volume of solution in the petri dish is always the same 3) The measurement of the potato is always the same 4) The potato is always skinless Obtaining Evidence After steadily changing the concentration of the sucrose solution I found out the following results before repeating the experiment another time. A Table To Show the Change in Mass of Potatoes in Different Concentrations of Sucrose Solutions for the first experiment Concentration (mol) Mass before Mass after % gain/loss 0.00 9.44 10.68 13.14 0.25 10.45 10.65 1.91 0.50 10.28 8.77 -14.69 0.75 8.70 6.60 -24.13 1.00 11.44 8.31 -27.36 A Table To Show the Change in Mass of Potatoes in Different Concentrations of Sucrose Solutions for the second experiment Concentration (mol) Mass before Mass after % gain/loss 0.00 11.00 12.17 10.64 0.25 11.21 10.84 -3.30 0.50 10.70 9.67 -9.63 0.75 10.11 7.73 -23.54 1.00 7.78 8.32 6.94 For the next table I calculated the averages of the change in mass of potatoes in different concentration of sucrose solution of the first two experiments. However, when working out the averages I did not include the anomalies. An anomaly is something that you do not expect; an irregularity. A Table To Show the Change in Mass of Potatoes in Different Concentrations of Sucrose Solutions for the average of the two experiments Concentration (mol) ...read more.

Conclusion

These are called anomalies. I could have obtained better results if I had performed more experiments, to do this I would have needed more time; more tests would have made the average more accurate. With more time I could have experimented with more concentrations. With these extra concentrations a trend in the results would be easier to see. If a microscope was used to view the potato cells after each experiment we may have noticed if the cells were either plasmolysed or had under gone lysis. As you can see the experiments were repeated twice, each time the results are similar. This should show that they are reliable enough to make a firm conclusion. There are a number of alterations that would allow us to investigate further into osmosis. o Test how different semi-permeable membranes could effect osmosis. This could be done by using other organisms instead of a potato. o Investigate the concentration at which the potatoes will undergo plasmolysis. o Investigate how changing surface area of the potato pieces and different volumes of solution affect the rate of osmosis. o Investigate what affect temperature has on osmosis o Investigate what affect sunlight has on osmosis o Investigate the size of the pieces of potato that osmosis occurred most rapidly o Investigate how long the poato piece had to be in a certain solution before it plasmolysed o Investigate how long the poato piece had to be in a certain solution before it under went lysis ...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

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

    Investigating the effect of Sucrose Concentration on the Rate of Osmosis in Potato Chips.

    5 star(s)

    This would possibly distort the results and it would be useless to do the experiment. The experiment proves that there is variation even within the same potato because I used chips from the same vegetable with the same length but their masses were still different to one another.

  2. Marked by a teacher

    How does the concentration of a sucrose solution affect the rate of Osmosis in ...

    5 star(s)

    The only anomaly is the one for 15%, which has a decrease of 0.3%, and according to the rest of the results it should be an even larger decrease in mass (larger than 0.5%). The results have shown that the experiment works quite well, and the ranges that I have chosen are appropriate.

  1. Marked by a teacher

    Investigating the effect of sucrose concentration on osmosis in potato cells

    4 star(s)

    o I will measure the percentage change in mass to find out how concentration affects osmosis. I will do this by measuring the mass using a balance before and after the potato tissue goes in the sucrose solution and working out the percentage change.

  2. To investigate the factors that effect osmosis in living tissue.

    Given that the radius' used shall be 0.5cm,0.7cm and 1cm the cross sectional area may thus be found by the formula ( x r2. The cross-sectional areas are thus 0.79, 1.54 and 3.14cm2. Two different concentrations will be used, i.e.

  1. Osmosis Coursework. Investigation Of The Effect of Different Concentrations of Sucrose Solution on Potato ...

    The cell will have decreased in volume and mass because of the decrease in water. If the potato tissue is placed in a solution with the same water concentration of that inside the cell, water will move out of the cell at the same rate as it enters the cell.

  2. Osmosis, What is the effect of sucrose concentration on the rate of osmosis in ...

    The potato that I use for my real experiment may not be the same variety, size, or from the same plant so 0.38 Moles/Litre an estimate.

  1. Osmosis is defined as 'the movement of water molecules from an area of high ...

    To make the mass readings more fair, I will take each chip, roll the chip gently on a paper towel, to remove all excess solution, and I must not squeeze the chip. I am also going to use the same balance to weigh my chips.

  2. Finding out the effect of osmosis on potato chips at different concentrations of sucrose ...

    I also stored them safely on the desk making sure know-one could knock into the solutions. Analysing evidence and concluding In this investigation we have found out that osmosis is a very importing factor in this experiment. Osmosis is defined as the movement of water molecules across a partially permeable

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