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

The aim of this experiment is to investigate the movement of water into and out of plant cells by osmosis. The cells chosen for study will be taken from potato as they provide a ready supply of homogeneous material.

Extracts from this document...

Introduction

Osmosis Aim - The aim of this experiment is to investigate the movement of water into and out of plant cells by osmosis. The cells chosen for study will be taken from potato as they provide a ready supply of homogeneous material. Osmosis is the diffusion of water molecules across a partially permeable membrane from a high concentration of water to a low concentration of water. Movement of substances takes place through the cell membrane, which separates the different substances in the cell from its surroundings. This type of membrane allows small molecules such as water to pass through it, but it denies entry to large particles, such as glucose, to pass. This membrane is called a partially permeable membrane. The amount of water inside a cell is called water potential. Variables that may affect the experiment (rate of osmosis) - * Concentration of Salt Solution * Size of the potato * Temperature of surroundings * Time Prediction - Osmosis is the movement of water molecules, where water molecules diffuse from a highly concentrated region, to a region in which they are less concentrated. ...read more.

Middle

Weight of potatoes Before Experiment (g) Salt Concentration (%) A B C 0 0.67 0.73 0.77 0.5 0.75 0.80 0.67 1 0.73 0.68 0.72 1.5 0.64 0.60 0.67 2 0.78 0.64 0.73 2.5 0.74 0.74 0.71 3 0.68 0.64 0.70 Weight of potatoes After Experiment (g) Salt Concentration (%) A B C 0 0.87 0.78 0.89 0.5 0.71 0.79 0.63 1 0.71 0.64 0.71 1.5 0.58 0.54 0.58 2 0.58 0.51 0.59 2.5 0.51 0.53 0.50 3 0.40 0.42 0.46 Observations: 0 - Hard, 0.5 - Fairly Hard, 1 - Hard, 1.5 - Soft, 2.0 - Slightly Soft, 2.5 - Very Soft and 3 - Very Soft. Change In Mass (g) Concentration Of Salt Solution (%) A B C Average Change In Mass (X) Average Start Mass (Y) Percentage Change In Mass (X/Y *100) 0 0.2 0.05 0.12 0.123 0.723 17.01% 0.5 0.04 0.01 0.01 0.02 0.73 -2.73% 1 0.2 0.04 0.01 0.023 0.71 -3.23% 1.5 0.06 0.06 0.09 0.07 0.636 -11.01% 2 0.2 0.13 0.15 0.16 1.663 -9.62% 2.5 0.23 0.21 0.21 0.216 1.72 -12.55% 3 0.28 0.22 0.24 0.246 1.553 -14.30% The graph clearly shows as I increase the concentration of the salt solution, the weight change (%) ...read more.

Conclusion

would expect the beaker which contains plant tissue of 5% salt to decrease slightly compared to the plant tissue which decreases more in size and mass because it was placed in a solution of 10% salt. This is because water molecules move from a high concentration i.e. the solution, to a low concentration i.e. the plant tissues. Therefore, the potatoes cylinders in higher water concentrations will become swollen and increase in mass compared to the salt concentrations. After a certain period of time I predicted that the plant tissue will not be able to increase in size any further this is because the plant tissue is completely swollen. And the opposite will happen if I place the plant tissue in a solution with higher salt concentration than water concentration. I predict that the potato tissue will have become soft and weak, and its size will decrease more according to the concentration. This is because osmosis is the diffusion of water from a region of high concentration of water i.e. plant tissue, to a region of low concentration i.e. salt solution. Using this I can say that my prediction was correct. ?? ?? ?? ?? By David Pryse ...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

    An experiment to investigate how the effect of varying concentrations of salt solutions play ...

    4 star(s)

    0.5 2.40 1.95 - 0.45 -19 3.05 2.40 - 0.65 -21 2.63 2.78 + 0.15 6 1 3.11 3.28 + 0.17 5 3.05 3.17 + 0. 12 4 3.37 3.41 + 0.04 1 1.5 2.23 2.55 + 0.32 14 2.41 3.10 + 0.69 29 1.98 2.67 + 0.69 35 2

  2. An experiment to investigate osmosis in plant tissue.

    Keep the test tubes in the same area so they will be in the same conditions, don't leave one in the sun and the others in shade ect. However some variables cannot be controlled: i. The initial potato chips all vary in density which means they might be able

  1. Efeects of Osmosis in Plant Cells

    This will prevent any anomalies or errors interfering too much in my end. The visking tubing bags will then be left the solutions for 24 hours. After this period, they are taken out of the beaker, dried and re-weighed. The overall change in mass will then be worked out and then the percentage change in mass.

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

    Molarity Sample Weight Original: New: Loss/Gain (g): Loss/Gain (%): Average Loss/Gain (%): 0.0m 1 1.17 1.34 + 0.17 + 14.53 +12.66 2 1.05 1.18 + 0.13 + 12.38 3 1.11 1.25 + 0.14 + 12.61 4 1.07 1.20 + 0.13 + 12.15 5 1.03 1.15 + 0.12 + 11.65 0.05m

  1. An experiment to show the movement of water into and out of plant cells ...

    weak solution it will most likely mean that it will swell up and become turgid, taking in all the water it can possibly take in. (Written from Hypothesis). Scientific Knowledge Osmosis is the passage of water molecules from a weaker solution into a stronger solution, through a partially permeable membrane.

  2. Investigating The Effect Of Osmosis On Plant Cells And Tissue

    Getting and experimenting with the exact measurement of concentration of sugar solution is extremely vital to the experiment. If the volume of one solution in a test tube is higher or lower than another, it will affect the pattern of results.

  1. How Does Osmosis Affect Plant Cells?

    My results from the test in the sugar solution were fairly accurate with no anomalies as seen in the graph, but my results in the water solution had a few anomalies. As time went on there was a consistent increase in mass and length, but once the cuttings had been

  2. To Investigate water uptake by Plant Cells

    As cells use food and energy, they produce carbon dioxide waste. This must be removed before it poisons the cells. Carbon dioxide diffuses from cells into the blood, which carries it away to the lungs to be breathed out of the body.

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