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

effects of concentrations of sugar solutions on potato chip cells

Extracts from this document...

Introduction

Biology Coursework My task is to investigate the effects of concentrations of sugar solutions on potato chip cells. Planning My controlled variables are to be the temperature the experiment is performed at, the starting length of the potato chips, the total quantity of solution to be used and the amount of stirring for each test. The effects of these variables if uncontrolled are listed in the table below. Variable How it will affect the investigation. How it will be controlled Temperature The higher the temperature the quicker the experiment will be so if one test was to be at a higher temperature than another then the test would be unfair. Osmosis is not directly affected by temperature, although the general mobility of molecules increases with temperature, and this means a slight increase in osmotic effects with temperature. Also the rate of the experiment could be increased when heated due to the collision theory. The collision theory states that when an experiment is heated the particles and molecules will move quicker, therefore giving them a higher chance of moving through the partially permeable membrane of the cell membrane. I will control this by taking all the tests at the same time at room temperature. Starting length of chips The larger the surface area, the more osmosis occurs, therefore proving unfair if any chips have a different surface area to another. Any larger chips would have been able to diffuse out more or taken in more water molecules, depending on the concentration, because it is has a large inner area and surface area than the smaller chips. I will cut the chips so that they are all the same length, width and depth. ...read more.

Middle

The following table shows how these items will produce reliable results. Plan For my experiments I will use six different concentrations of sucrose solution: 0M, 0.2M, 0.4M, 0.6M, 0.8M and 1M. This will provide me with a large range of results, from which to base my analysis on. I will test each concentration three times, so in total will need 18 boiling tubes. I will always use a total of 20mls of solution. I will weigh and record the mass of each chip after cutting them all down to 5.3cms in length. This means I will be able to collect reliable data for my results. I will place all the chips in the solution as quickly as possible so they all have the same time. I will then leave them for 24 hours and then take them all out of their solutions. I will do this again as quickly as possible to make it a fair test. I will surface dry them with a paper towel to make sure I am only weighing the potato chip, rather than the potato chip and any excess solution. I will weigh each chip again so I can tell the mass change, and percentage difference later. These are how I will mix all my concentrations so they are all exactly the same. Concentration of sucrose solution/ M Volume of sucrose solution added/ cm3 Volume of water added/ cm3 0 0 20 0.2 4 16 0.4 8 12 0.6 12 8 0.8 16 4 1.0 20 0 I will carry out my experiment as shown in the plan above. The evidence I will collect is the mass change of the potato chips in the range of different solutions. ...read more.

Conclusion

This will mean that some chips would be in a lower concentration so the results would be affected. You can cover the tops of the boiling tubes with cling film and place them in a cool, dark place in a room. The chips might not have properly been dried. This would mean that you might be weighing at the end of the experiment the mass of the chips and excess sucrose solution. I could dry them with a paper towel and weigh them, then dry them again and reweigh and continue to do this for each one until I get a constant weight. Evaluation of Procedure I think my experiment went according to plan and the procedure I used was quite suitable. It was a fair test as all the chips had the same amount of sucrose solution, the same length of time and the conditions they were left in were all the same. There were more limitations to my experiment though: * Measuring cylinder - It would have been much more accurate to use a burette or graduated pipette. * Chips from different potatoes - Different potatoes have different dilutes and minerals, so some potatoes might have behaved differently. To improve on this you could take all your chips from one potato. I think the limitation that had the most significance was if the chips were not dried properly. If you did not take off all the excess water then the results would be different and incorrect. Next time, to improve my experiment I will use a burette or graduated pipette to measure out my concentrations of sucrose solution and make sure that I spend more time drying my chips after the experiment to ensure I get the maximum in reliability in my results. Page 1 of 7 Lizzie Wright ...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

    Biology coursework planning - the effect of lead chloride on the growth of cress ...

    5 star(s)

    mediums Medium in which cress seeds are grown Average length of shoot of cress seeds (mm) Cotton pad 46.7 Filter paper 36.0 Cotton wool 39.9 Note: All figures in the table are correct to 3 significant figures as per the Institute of Biology guidelines.

  2. Marked by a teacher

    The Effect Of Temperature On The Permeability Of The Cell Membrane

    3 star(s)

    skin if used incorrectly, however the position of the first aid kit was known in case of an emergency, an apron was used to protect the clothes from the red pigment anthocyanin which stains clothes Control Experiment A control experiment is required to ensure that nothing else apart from the independent variable will affect the results.

  1. Osmosis. Question 5: In a lab setting, examine the effects of osmosis on plant ...

    the cylinders were allowed to dry out because they are not in any kind of solution where there's a difference in concentration. Although most of the water would be extracted out of the cells, it is mostly due to evaporation or absorption of water molecules.

  2. Investigation into the effects of different

    there is an increase in the number of DNA , as DNA replication occurs and the subsequent mitotic stages develop .This results in the size of the mother cell to reach a critical size. When this occurs yeast buds are initiated, as when reached this critical size the cell wall weakens, due to the tension.

  1. An investigation into changing the concentration of sucrose soltion on the rate of osmosis ...

    And because the plant cell wall is so strong and rigid the cell will not burst. Sometimes in plant cells there is a process called plasmolysis which occurs. This is where the protoplast begins to decrease in size and water moves out of the cell, due to a higher water potential outside the cell.

  2. the role of the microbiology department

    HIV (Human Immunodeficiency Virus) Disease The features of HIV Pathogen Human Immunodeficiency Virus Methods of transmission In s***n and v*****l fluids during s****l intercourse, infected blood or blood products, contaminated hypodermic syringes, mother to fetus across placenta, mother to infant in breast milk. Global distribution Worldwide, especially in sub-Saharan Africa and South-East Asia Incubation

  1. Design an experiment to investigate the effect of temperature on the movement of a ...

    Also I could not use a Bunsen burner because it does not have an even temperature distribution, and it would not be possible to have different temperatures for each piece of beetroot. I will also check the temperature of the water bath with a thermometer before I place the test

  2. Hypothesis: To investigate the effect of different concentrations of ethanol on the permeability of ...

    for this purpose. (Information from The Hutchinson: Dictionary of Science) The pH affects proteins that make up about 70% of most cell membranes. Proteins are made of amino-acids with a variable number of nitrogen and oxygen atoms in the protein.

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