• 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

An investigation to find out the water potential of potato cells

Extracts from this document...

Introduction

An investigation to find out the water potential of potato cells using sucrose solution Aim The aim of this experiment is to investigate the movement of water into and out of cells by osmosis. The cells chosen for study will be taken from potatoes as they provide a ready supply of uniform material. Hypothesis My hypothesis is that as you increase the concentrations of the sucrose solutions there will be a net loss in mass of the potato cores, due to the water molecules moving out of the potato cells by osmosis. Background knowledge Water potential is a measure of the ability of water molecules to move from one region to another.' The more water molecules there are per volume of the cell the more likely that by random movement they will collide with the cell's plasma membrane, and travel out of it. Pure water has a water potential of 0. As all solutions have less water molecules per volume than pure water they have lower water potential, therefore all solutions have negative water potentials. The movement of water molecules is not totally random. ...read more.

Middle

Suitable background to observe variations in the tissue. Tweezers Enables potato to be held securely without skin contact, increasing accuracy of results. Tissue paper Used to blot the sides of the potato chips meaning the mass is not affected by any remaining solution on the surface of the potato. Each chip is blotted once, making the effect on mass uniform across all chips Electronic scales Measures the mass of potato chips, in grams, to two decimal places. To ensure the results are reliable use the same balance throughout the experiment Safety Apparatus Safety evaluation Boiling tubes Handle carefully to avoid breakage. Dispose of in sharp bin Potato chipper Minimal risk if used correctly Scalpel Sharp, avoid contact with blade Distilled water Minimal risk Sucrose solution Minimal -use fresh to avoid microbial contamination Tissue paper Minimal risk Electronic scales Avoid contact with liquids Potato tubers Minimal risk Beakers Handle carefully to avoid breakage. Dispose of in sharp bin Tube rack Minimal risk Tweezers Minimal risk White tile Minimal risk Measurements In my experiment, 2 sets of results are going to be taken. However, in my investigation, I am going to use the class results, as it will be more accurate. ...read more.

Conclusion

from 0-to1 mole, this would enable me to get more accurate results, and The main variable with the experiment was the drying of the chips, as some may not have been dried as much as the others may, if they were not dry, this could effect the concentration of the sugar. In addition, different areas of the potato may have different concentrations of cells, which can affect the experiment, although it is a minor point it could have a great impact also not all potatoes in the test are exactly in the same size as there will be measuring errors in both instrument and human. Even if the potatoes are in the same size, may not contain same no. of cells which will affect the rate of osmosis. When you cut the potato, you cannot avoid to "destroy" some of the cells. It also causes leakage of cell contents to the outside which causes shrinkage of the cells. Systematic errors like the measurement error when making the solutions can also cause errors. These are all minor points because they cannot be improved in a more accurate way except having better measuring instruments would help. ?? ?? ?? ?? .Page 1 of 9 Y.12B Janice Lau ...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. An Investigation to determine the Water potential of Potato cells.

    Incipient plasmolysis is when pressure potential has just reached zero:coab abr seababw orab abk inab foab ab. ?p = 0 , so ?w = ?s shayon, please do not redistribute this writing. We work very hard to create this website, and we trust our visitors to respect it for the good of other students.

  2. Investigate the water potential of potato tissue and compare this with the water potential ...

    suggest that leaving the potato and apple tissue in the sucrose solutions for too long will effect the osmotic balance. In 0M solutions, the potato cells started to gain in mass and then lost mass.

  1. The endeavour of this investigation is to ascertain if there is any effect of ...

    not clear due to poor resolution of the light microscope - there was a tendency to estimate the number of cells so therefore the figures were not totally precise or accurate - the experiment was only conducted once. Repeats would have ascertained any trends or findings The preliminary experiment may

  2. Osmosis investigation

    I unfortunately used one scale to measure my chips' mass before they were put into solutions and another to measure their mass after. This means that there may be a roughly 0.1g difference between the two results. Another reason for anomalies may be the cutting of the potato chips.

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

    C 1.01 0.93 - 0.08 - 7.92 D 1.00 0.93 - 0.07 - 7.00 E 1.00 0.95 - 0.05 - 5.00 The weight increased in each potato sample until just above 0.25 and below 0.30. This shows the solute content of the potato is equal with the concentration of the bathing solution.

  2. Our aim was to discover the water potential of potatoes cells using different concentrations ...

    potato cells will have a water potential of the equivalent of around 0.3M of sucrose because this was the solution that had little net movement of water, this water potential is -900kPa (ref- teacher support: coursework guidance OCR- graph). Variables: * Concentration of sucrose solution - as the concentration of

  1. Osmosis Investigation

    safety precautions to take and have utilized the required equipment appropriately; I have placed the potato on a raised platform before forming the potato cylinders preventing the chance of any injury to my hands. Furthermore, I was extremely careful when using the razor blade to cut the potato cylinders to an exact length of four centimeters each.

  2. INVESTIGATING OSMOSIS AND WATER POTENTIAL IN POTATO CORES

    to cut the potato this will give the same mass and dimensions of the potato core. Mass is bound to vary slightly this is why a percentage will be used to compare the change in mass using the original mass and the end mass.

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