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

Determination of Water PotentialOf Potato Tissue

Extracts from this document...


EHSEN KHOKHER Determination of Water Potential Of Potato Tissue Introduction: Osmosis: is the movement of water through a semi permeable membrane from a high water concentration to low concentration. Osmosis is movement of water, which takes place through the cell membrane that separates the cell contents from the surroundings. Cell membranes allow some substances to pass through and stop other substances from passing: they are partially permeable. In general, substances pass through a membrane if their particles are smaller than the pores in the membrane. When a partially permeable membrane separates two solutions, water passes through the membrane in both directions. The net flow of water is from the more dilute solution to the more concentrated solution. The flow continues until the two concentrations are equal. The flow of water from a more dilute solution to a more concentrated solution is called osmosis (see diagram). Partially permeable membrane Concentrated Sugar Solution Dilute Sugar Solution Sugar Molecule Water Molecule Water potential is how likely the water is to leave the solution. High water potential is when the water is highly likely to leave. ...read more.


Mean length of potato at end CHIP 2 (cm) Mean length of potato at end CHIP 3 (cm) Mean change in length of potato (cm) Mean Chan-ge (cm) % Mean chan-ge in leng-th 1.0 6.0 5.5 5.3 5.5 5.43 -0.57 -9.5 0.75 6.0 5.5 5.4 5.4 5.43 -0.57 -9.5 0.5 6.0 5.9 6.0 5.9 5.93 -0.07 -1.17 0.3 6.0 6.0 6.0 5.9 5.96 -0.04 -0.5 0.2 6.0 6.0 6.2 6.0 6.07 +0.07 +1.17 0.1 6.0 6.0 6.4 6.0 6.13 +0.13 +2.17 Table 2 Showing Water Potential Conc. Of Sucrose (M) Water Potential (kPa) 0.05 0.13 0.10 0.26 0.15 0.41 0.20 0.54 0.25 0.68 0.30 0.86 0.35 0.97 0.40 1.12 0.45 1.28 0.50 1.45 0.55 1.62 0.60 1.80 0.65 1.98 0.70 2.18 0.75 2.37 0.80 2.58 0.85 2.79 0.90 3.00 0.95 3.25 1.00 3.50 Conclusion: The mean % change in length of potato tissues increased by 2.22% in the 0.1M sucrose solution. This is because the water concentration of the sucrose solution was higher than that of the potato tissue. Water moved from the more concentrated water to the less concentrated potato tissues resulting in full turgor tissues with greater length. ...read more.


not to 0g but to 0.00g. This is to get more accurate results. There was one anomalous result, which was the 0.75M sucrose concentration; this was anomalous because it was way off from the line. Looking at my graph it should have been -0.6 or -0.7%. This may have been caused by human error, which was the making of the sucrose concentrations and measuring the potato chips, or one out of my six results could have been more inaccurate, and changed the average drastically. Or perhaps the potato chip was not cut accurately, or that part of the potatoes, cells did not loose/gain mass well. One or two of my results did vary a lot for the same concentration. The fact that a certain part of the potato may not be the same as another was shown as the chips all of the same length but we did not weigh them so they might not have been the same weight, or even close. I could extend my enquiry by testing the percentage change in mass with molarity using more concentrations and different kinds of potatoes. By this I mean using potatoes of different seasons, perhaps different types of potatoes. Then I could find out whether osmosis occurs with the same patterns and trends with any potato. ...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

Here's what a teacher thought of this essay

4 star(s)

A clear account with good explanations but confusion over the use of some terms and no discussion of variables.

Marked by teacher Adam Roberts 20/05/2013

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

    Biology Coursework - Osmosis

    5 star(s)

    No running. Also wearing safety goggles, would prevent an injury to the eye. Spillages - Spilling any of the solutions could result in a slippery and sticky floor. Take care when transporting fluids, make sure that paper towel is available, and clear up any spillages promptly.

  2. Marked by a teacher

    Isotonic Point of Potatoes

    5 star(s)

    quite smooth * The colour of the potato changed from bright yellow to pale yellow. 0.2M - * The potato cylinders looked slightly longer than before * They were hard but not as much as those of 0.1M solution. * They did not bend very easily.

  1. Marked by a teacher

    To determine the water potential of a potato tuber cell using varying salt solution.

    5 star(s)

    Therefore you should cut the potatoes jus when it is necessary. * Make sure all the boiling tubes are in the boiling tube racks. * Take the bottle of distilled water and empty some out into one of the beakers.

  2. Marked by a teacher

    An Experiment to determine Water Potential in Potato Tissue.

    4 star(s)

    This is quite an important factor because the heavier the potato, the more cells it contains, thus more osmosis. 4. The length of time the potatoes are in the solution- the time that the potatoes were kept in the solution was the same.

  1. Marked by a teacher

    Science Coursework: Investigating Osmosis in potato tissue

    4 star(s)

    We had measured out 100ml for each boiling tube because we wanted it to be a fair test. Then we cut up and measured the two bits of potato that were going into the boiling tubes. They were equal mass and length for as fair test.

  2. The determination of the Water Potential of Potato Tuber Cells

    0.11 0.06 0.02 0.01 -0.15 -0.20 % change in mass 11.96% 5.94% 1.75% 1.05% -15.63% -21.51% Discussion My results showed that as the molarity of the solution increased, the weight loss in the potato's also increased. This is due to the process known as osmosis and water potential within the different substance strengths.

  1. Aim To determine the water potential of a potato tuber cell

    the potato cylinder before and after the solution Boiling tube 12 To place the solution and potato cylinder in Rubber bung 12 To stop evaporation from occurring and to stop foreign objects from entering. Filter paper 12 To absorb any excess solution from the potato cylinder Boiling tube rack 2

  2. Water potential of potato tuber cells - the weighing method.

    0.4 Molar solution had water potential of -1120kPa and thus the potato tubers had an average mass decrease of 18%. This must mean that the 0.4M of sucrose is greater than the concentration of sucrose in the potato cells.

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