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

The effect of temperature on the cell membranes of beetroot cells and amount of pigment released.

Extracts from this document...

Introduction

The effect of temperature on the cell membranes of beetroot cells and amount of pigment released. Apparatus * Corer size 4 * White tile * A Beetroot * Automatic Water Bath * Segregated knife * A thermometer * Stopwatch Method: * First take the white tile and the corer. Then collect a cylinder of beetroot by pushing the corer into the beetroot and withdrawing it. The cylinder remains inside the corer- so push it out with the end of a pencil. * Collect 3 cylinders, and then cut them into 6 pieces of 3 cm with a segregated knife. * The beetroot was cut to 1cm. Because the beetroot has been cut some of the cell membranes had been broken, which means some anthocyanin will leak out. This must be completely washed off in order to maintain the reliability of the results. * The water bath must then be heated to 20oC (the first temperature for the experiment) * Once the water bath is at the correct temperature (measured using the thermometer), one piece of beetroot is placed into the hot water directly and left for exactly1 minute (using a stopwatch). ...read more.

Middle

However when we increase the temperature the relatively weak forces holding the different parts of the polypeptide chains together (like hydrogen bonds, sulphur bridges and ionic bonds) can be disrupted very easily- this damages the vacuole and makes holes in the cell membrane, inducing leakage. The cell membrane is also damaged and so diffusion of betalain occurs through the partially permeable membrane by osmosis- the betalain molecules move by diffusion from an area where they are more highly concentrated to an area where they are at a lower concentration, along a concentration gradient. The reason why the amount of betalain pigment increases rapidly (from 40oC to 60oC) is because most mammalian protein's denature and tertiary structure unravels (the strong covalent bonds between the R groups of amino acids in the polypeptide chains are destroyed) at temperatures over 40oC. The reason why the curve starts to flattens out (between 60oC and 80oC), is because although the denaturing of the protein causes a rapid rise in the amount of betalain released to start with, when the temperatures begin to get higher still, the protein's tertiary structure blocks some of the holes in the cell membrane and therefore slows down the release of betalain. ...read more.

Conclusion

Another limitation was cutting the beetroot into pieces. The pieces cut had roughly the same surface area to volume ratio- but not exactly the same. This would have had a slight effect on my results because the rate of diffusion of betalain particles across the plasma membrane is increased, as the surface area of the beetroot increases. So the slightly thinner and smaller pieces of beetroot I cut would have released more betalain from their vacuole. I only looked at one type of plant cell, so I can not be sure that every plant cell and indeed eykaryote- which have different plasma membranes, that may be adapted to cope with heat better or worse than beetroot cells willl have the same results. I can firmly conclude that there are no apparent anomalies in my results and none of my sources of error or limitations of my experiment are enough to deem my results unreliable. However the sources of error and limitations in my results may have made my results slightly less accurate, but other students in my class found the same patterns occuring and roughly the same results- which would vary slightly between each beetroot anyway. ...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 Molecules & 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 AS and A Level Molecules & Cells essays

  1. Marked by a teacher

    Beetroot Experiment. The purpose of this experiment is to determine the effect of temperature ...

    4 star(s)

    Variables Dependent variable = temperature. The purpose of this study is to investigate the effect of temperature on the plasma membrane. In order to carry out this investigation, the experiment will be repeated at several temperatures to discover at which intervals the plasma membrane begins to break down.

  2. Marked by a teacher

    Investigating the effect of temperature on the movement of pigment through beetroot cell membranes.

    4 star(s)

    Cold distilled water added to speed up the cooling process. 5. Leave the beetroot discs in the sample tubes of distilled water for exactly 30 minutes. 6. After 30 minutes shake the sample tubes vigorously and remove the beetroot discs.

  1. Marked by a teacher

    The Effect of Ethanol Concentration on the Permeability of Beetroot Cell Membranes to Betalain

    3 star(s)

    2 m - Ethanol Solutions: beaker 1 200cm� Ethanol solutions 1080 cm� water, 720 cm� 100% ethanol 0 - 80% Boiling tubes 10 - Chop Sticks 9 pairs - Bungs 10 - Test tube racks 3 - Water Bath: Water Bath 1 - thermometer 1 - Colorimetry: colorimeter 1 -

  2. Marked by a teacher

    effect of temperature on beetroot pigment through membrane

    3 star(s)

    - Hair must be tied back, to give a clear view of the working area and away from open fire. Equipment / per temperature points experiment - - 3 x Boiling tube - 2 x 500 cm3 beaker - 2 x Thermometers - 9 x Beetroot disks - 200 cm3

  1. Marked by a teacher

    An investigation to examine the effects of temperature on membrane stability in beetroot, by ...

    3 star(s)

    Hydrophilic R-groups are soluble within water and are so water 'loving', whereas hydrophobic R-groups are not soluble in water and are water 'hating'. The properties of the R-groups on amino acids within a protein are very important as they affect the characteristics and functions of the protein.

  2. Marked by a teacher

    The effect of temperature on the permeability of beetroot membrane

    3 star(s)

    The confidence limits also show if the results are significant or insignificant. I will also be using standard deviation which shows me the variation between the results. The lower the standard deviation the more accurate the results. * Decide how much replication you will need for successful analysis I will

  1. Permeability of Cell Membrane in Beetroot Cells

    greater the increase in heat, the greater the energy of the molecules. The more energy the molecules have the more they move around, this is how the pigment leaked out. At lower temperatures, the molecules were moving around slowly so there was very little leakage, however, when the temperature increased

  2. An experiment to find of the isotonic point of root vegetables cells in contents ...

    Therefore the water molecules will enter the root vegetable at this concentration by osmosis and will create a pressure potential. Water potential equation This pressure potential will cause the protoplast in the cell and this will be pushed against the cell wall.

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