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

Osmosis In Potatoes.

Extracts from this document...

Introduction

AT1- Osmosis In Potatoes Aim: Investigate the movement of osmosis through a selectively permeable membrane, in this case potato. Introduction: Osmosis is the movement of water through a semi permeable membrane, separating solutions of different concentrations. The water passes from a region of high concentration to a region of low concentration, until the two concentrations are equal in concentrations of water. Many cell membranes behave as semi permeable membranes, and osmosis is a vital mechanism in the transport of fluids in living organisms, for example, in the transport of water from the soil to the roots in plants. If a cell is in contact with a solution of lower water concentration than its own contents, then water leaves the cell by osmosis, through the cell membrane. Water is lost first from the cytoplasm, then the vacuole through the tonoplast. The living contents of the cell contracts and eventually pulls away from the cell wall and shrinks, this is known as Plasmolysis. If you put a plant cell in water, water enters by Osmosis, then swells up. However, the cell will not burst. This is due to the fact that the cell walls are made from cellulose, which is extremely strong. ...read more.

Middle

Weight (mm) Before After Before After Before After 0 molar 5mm 5 8mm 8 33mm 33 36mm 34 0.57g 0.48 0.67g 0.5 0.1 molar 5 5 8 7 33 33 35 34 0.72 0.86 0.91 0.90 0.15 molar 5 5 7 6 33 33 35 33 0.64 0.75 0.71 0.81 0.2 molar 5 5 6 7 33 33 32 33 0.73 0.75 0.81 0.77 0.25 molar 5 5 6 5 33 33 34 29 0.65 0.66 0.68 0.66 0.3 molar 5 5 5 5 33 33 33 25 0.68 0.73 0.85 0.57 1 molar 5 5 4 4 33 33 28 23 0.78 0.75 0.82 0.57 Concentration Average change in Width (mm) Average change in Length (mm) Average change in Weight (g) 0 molar 3 2 0.06 0.1 molar 2.5 1.5 0.11 0.15 molar 1.5 1 0.065 0.2 molar 1.5 -0.5 0.05 0.25 molar 0.5 -3 0.015 0.3 molar 0 -4 0 1 molar -1 -5 -0.14 Analysis Of Graphs: � Graph 1 'Average change in width' shows me that the higher the concentration, the more width the potato chip will lose. For example, the potato chip to gain most width was the one in pure water, or 0 molar concentration. ...read more.

Conclusion

However, in doing this we could have removed water that was not excess, and altered our results. Another inaccuracy was when we put the potato chips into the solutions, because it was impossible to not leave a small interval between each test tube. The first test would have been going for a few seconds longer than the last. I do not know how I would resolve this problem. I also found 2 anamalous results. The first, was on the graph which showed average change in width, the anamalous result was for the test for 0.2 molar solution. The second was on the graph that showed average change in weight, the anamalous result was for the test with 0.1 molar concentration. The main reason for this is inaccuracy. I used the mean when plotting my graphs. That way, the information is clear and can be understood quickly, however, the disadvantage of this, is the fact that if one of the two results is inaccurate, the mean will also be. I believe that this is the reason for the anamalous results. I could extend this AT1 by investigating osmosis with a different factor as opposed to concentration of water. I could investigate the effects of temperature on osmosis, or surface area. This would give me a very clear understanding and knowledge of osmosis in potatoes. ...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

    Human Reproductive System

    4 star(s)

    Other cells in the tube's endothelium nourish the egg and lubricate its path during its stay inside the fallopian tube. Once inside the fallopian tube, the egg and the sperm meet and the egg is fertilised. The fertilised egg will travel through the fallopian tube to implant in the uterus.

  2. Marked by a teacher

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

    4 star(s)

    Therefore, the surface area of all the potato strips should be the same for our comparisons of the rate of osmosis to be accurate. If all the strips do not have the same surface area, some will get more access to the solution, while some strips will get less access.

  1. Marked by a teacher

    The Effect Of Temperature On The Permeability Of The Cell Membrane

    3 star(s)

    the water expands the cholesterol, glycoproteins and phospholipids, which apply pressure on the membrane from the inside. The protein structure and the membrane is denatured and hence increases the surface permeability. All this suggests that high temperatures will allow the molecules to shake and vibrate more frequently.

  2. Osmosis in Potato cells

    0.00 0.00 Candice 10% Sucrose 4.44 4.23 -0.21 -4.73 55.00 52.00 3.00 5.45 Candice 15% Sucrose 4.59 3.79 -0.80 -17.73 55.00 51.00 4.00 7.27 Candice 20% Sucrose 4.68 3.95 -0.73 -15.60 55.00 50.00 5.00 9.09 Melanie 100% water 4.34 4.48 0.14 3.23 50.00 54.00 -4.00 -8.00 Melanie 5% Sucrose 4.22

  1. Investigating osmosis on swede cells.

    Knife- To cut the swede chips to a length of 3cm * Pipette- To accurately measure out the solutions * Funnel- To pour the solution into the boiling tube without spilling any solution. * Bungs- To place on every boiling tube to stop evaporation.

  2. The Endocrine System

    * In cases where glucose levels decrease, less insulin and more glucagon is released by the pancreas and targets the liver. The liver acts as a storehouse for glycogen, the storage form of glucose. When either of the above hormones target the liver, the following occurs * Insulin is released

  1. Investigation on Osmosis using a potato.

    So we have decided to put the potatoes in first then the solutions. To avoid any confusion the test tubes will all be labelled first. When using the balance, we will make sure that the balance is reading zero, before we put the 3 potatoes on it.

  2. What is the isotonic point of a plant cell?

    and can't have more than 1 molar because this is the maximum concentration of sugar that can be in the solution.. The rest of the concentrations were decided by dividing 1 molar by 5 (because I only had the resources and time to do six cups and we already had one used by the 0 molar solution)

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