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

To investigate the effects of osmosis, in a potato, whilst in glucose and water.

Extracts from this document...

Introduction

To investigate the effects of osmosis, in a potato, whilst in glucose and water. Aim I am investigating the effects of osmosis in a potato whilst in glucose and water. Prediction I predict that the potato will expand more in the glucose solution than in the water. I think this because osmosis will take place. Osmosis is where the membrane only allows certain molecules through. This is because the membrane is selectively permeable. Scientific Knowledge Osmosis is the diffusion of water or other solvents through a semi permeable membrane, from where it is in a high concentration to an area of low concentration. Turgor is the pressure exerted by fluid in a cell that presses the cell membrane against the cell wall. Turgor is what makes living plant tissue rigid. Loss of Turgor, resulting from the loss of water from plant cells, causes flowers and leaves to wilt. Turgor plays a key role in the opening and closing of stomata in leaves. Diffusion is the process by which there is a net flow of matter from a region of high concentration to one of low concentration. ...read more.

Middle

Safety It was not necessary to take any safety precautions, as there wasn't any thing dangerously in the experiment. Fairness So as to make this experiment fair we were very precise when measuring the amount of water and glucose. We also made sure that the five pieces of potato were the same length. As well as this we removed the pieces of potato exactly on time. Variable used The variable that we used was the amount of glucose and water that was used in each test tube. Affecting variables The possible variables were the: Temperature, Size of potato, Length of Time which the potato, was left in the solution, Amount of glucose and water in each test tube. Measurement We did two trials for the experiment and we did two ranges. The piece of potato was three centre metres each time and we used fifteen millilitres of solution. Results Time (minutes) Test tube 1. (15mm glucose) Test tube 2. (5mm water, 10 glucose) Test tube 3. (7.5mm water, 7.5 glucose) Test tube 4. (10mm water, 5mm glucose) ...read more.

Conclusion

(10mm water, 5mm glucose) Test tube 5. (15mm water) 5 3.3 3.2 3.15 3.0 2.9 10 3.3 3.2 3.1 3.175 3.1 My prediction is supported by the results as the slices of potato increased in size when they were placed in the mainly glucose solution more than when they were placed in the mainly water solutions in fact the pieces of potato shrunk in the pure water. The glucose obviously induces osmosis whereas water doesn't. Evaluation This experiment is not particularly accurate as it was quite hard to remove the potato exactly on time therefore some samples spent more time in the solutions than others. This could well explain why there were so many anomalies. In order to improve this experiment I think that we would have to find an easier method for removing the pieces of potato, so that we could get them out on time. There were anomalies in: The first attempt, test tube 3 at ten minutes (3.2) The second attempt, test tube 4 at five minutes (3.25) The second attempt, test tube 5 at five minutes (3.1) I think that if I were going to repeat this experiment then I would continue taking readings up to twenty minutes. As well as this I would run four experiments instead of only two. ...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

    Investigate the water potential of celeriac.

    5 star(s)

    The water potential of celeriac was found to be -1700 kPa. From the results, I can see that as the concentration of sucrose solution increases, the percentage change in mass of the celeriac discs decreases. For example, when the molarity of the sucrose solution is 0.2 mol dm-3, the average percentage change in mass is 14.4%.

  2. Marked by a teacher

    Determining the Water Potential of Sweet Potato Tissue

    4 star(s)

    So the fixed variables are: 1. Volume 2. Time left in solution 3. Temperature 4. Morality 5. Same vegetable used 6. Surface area In this investigation, I am going to calculate ? of the solution inside the cells by working out the molarity of the solution.

  1. Marked by a teacher

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

    4 star(s)

    * I will cut all the potato strips to a same length. * During measurements of water in a measuring cylinder, I will check the lower meniscus to avoid perplex errors. * I will check the Petri dishes and beakers for cracks to avoid any leakage of the solutions.

  2. Investigation into the effects of different

    and a polysaccharide (starch). Glucose; Maltose; Starch; Alternative hypothesis; Starch will have the least effect on the yeast growth. (Lowest number of yeast cells) Glucose will have the largest effect on yeast growth. (Highest number of yeast cells) Maltose will have a slight effect on yeast growth.

  1. the role of the microbiology department

    Methods of diagnosis Blood tests for antibodies to HIV. Annual incidence worldwide 33.4 million Annual mortality worldwide 2.5 million (one third due to Tb) Infection with HIV occurs by the transfer of blood, semen, vaginal fluid, pre-ejaculate, or breast milk.

  2. Investigation on Osmosis using a potato.

    readings possible which is to the nearest 2 decimal places or to the hundredth of a gram. But I believe one of the most important steps in the fair testing is to make sure that the potato is fully covered by the solution.

  1. Investigating the stomata density in Hedera up a wall?

    Hypothesis There will be no difference between the stomata density between the two sites. There will be a difference between stomata density of the two sites. Apparatus Hedera Leafs, Microscope, Lamp, Clear Nail Varnish, Slides, Hedera leafs, as they are easy to get results out off, and therefore more relievable to use for this investigation.

  2. This experiment aims to investigate the effects of 4 different types of fish food ...

    So far, no land carnivore has been successfully mass farmed and salmon farming is far from efficient (9). Even if we find an alternative food source for the salmon, we still depend on wild fish stocks for Omega 3 Fatty acids which the salmon require (salmon do not produce their own Omega 3 fatty acids)

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