• 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 Membrane Permeability

Extracts from this document...

Introduction

The effect of temperature on Membrane Permeability It is my aim to investigate whether or not temperature, or more specifically heat, affects the permeability of a cell membrane. Background Based on the fluid mosaic theory we believe the plasma membrane is composed of a phospholipid bilayer about 7-10 nm thick. This theory also suggests that proteins in bedded in the membrane are used for transporting substances across the membrane, creating pores for substances to pass through and act as carriers. Method i. The beetroot must be cut into cylinders and also washed as to remove any anthocyanin pigment that has leaked out the cells because of the cutting, then placed in distilled water ii. Heat 200cm3 of distilled water to 85oC in a sensible sized beaker iii. Whilst the water is heating, use a syringe to place 10cm3 of distilled water into each of ten test tubes. Label the tubes 85,80,75,70,65,63,60,55,50,45 (as these will be the temperatures used) iv. Cut 10 of the cylinder beetroot pieces into lengths of 5cm v. ...read more.

Middle

Results Temp (oC) Percent of light absorbed 85 95 80 92 75 93 70 75 65 17 63 9 60 24 55 11 50 4 45 15 We can see form this table that the percent of light absorbed decreases as the temperature the beetroot was subject to, also decreases. In other words, as the temperature increases, more of the red pigment was able to leave the cell into the distilled water and so the more pigment there was the more light would be absorbed. The above graph clearly shows that the amount of pigment released peaks at 700C, so we can say that at this point the membrane of the beetroot cell becomes severely damaged and a lot of the red pigment that is usually stored in the vacuole of the cell is no longer bound by the internal membrane surrounding the vacuole or the outer membrane. The graph also shows that at 60oC and 45oC the amount of pigment released also increases, however I do not believe that this is a usual occurrence and is an anomalous result. ...read more.

Conclusion

I also think that a different beaker of heated water should be used for each beetroot cylinder, as I found that much of the red pigment was escaping from the cylinder while still being heated, this could effect the results in the way that for the higher temperatures a lot of the pigment has already leaked out, and also that the red pigment in the water may attach to the beetroot cylinders used in the cooler temperatures test, for example at 80oC a lot of the red pigment leaked out of the cell, this would therefore give a lower light absorption rate and give the 50oC cylinder a higher absorption rate as the pigment may have attached to the cylinder while being heated. If I had more time I would like to repeat the experiment three times and gather three sets of results for each temperature and then use the arithmetical mean average. I would also like to test other types of cells using a similar method to examine if temperature effected these in the same way as the beetroot cells. Steven Spencer ...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)

    Independent variable = Betalain pigment as measured by colorimeter This is the variable that I am trying to measure in order to determine the structural integrity of the plasma membrane. Constant variables In order to make this a fare teat and to ensure that we are measuring the effect of

  2. Marked by a teacher

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

    4 star(s)

    I've tried to control this by making sure that all the slices are from the same beetroot so there shouldn't be too much variation in densities. By making these changes my experiment should provide more reliable results that can be accurately analysed.

  1. Marked by a teacher

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

    3 star(s)

    and onto board, keeping hands away from the end of the borer. Hot water - burn skin - water near electricity Wear a lab coat and take care when around the water baths and putting things in the water bath.

  2. Marked by a teacher

    Beetroot experiment. Aim: To investigate how the temperature affects the permeability of beetroot cells ...

    3 star(s)

    next cell via the plasmadesma or pits found along the cell membrane, and continues this method until reaching the endodermis. The second methods available for use is the sinoplast pathway in which the nutrient soaks in and then out of the cytoplasm of each cell , continuing to do so until it reaches the endodermis.

  1. Marked by a teacher

    Effect of different temperatures on the permeability of beetroot cell membrane.

    3 star(s)

    But the reason why the leakage was different for the beetroots at different temperature was during the 1 minute they were heated a molecule in the membrane was permanently damaged. I believe the molecule that was permanently damaged was the proteins in the membrane.

  2. Marked by a teacher

    effect of temperature on beetroot pigment through membrane

    3 star(s)

    Volume of liquid: The volume within the boiling tubes has to be the same; otherwise results will not be accurate as the more water in a boiling tube, the more dilution will occur. All volumes in the boiling tube are going to be 10cm3 (to 0.1cm3 degree of accuracy).

  1. TEMPERATURE ON BEETROOT PERMEABILITY

    Fig 1 The 3D structure of the beetroot's membrane (as shown in fig 1) is made up of, cholesterol, proteins, glycolipids and glycoproteins. Each of these all has specific functions in the cell membrane. The purpose of a cell membrane is to control the transport of substances moving into and out of a cell.

  2. An experiment to test the effect of different temperatures on the permeability of cell ...

    the transport protein, receptor protein, glycoprotein and all other carrier proteins would start to denature. When the proteins denature, they would change shape or rupture, and no longer fit in the membrane, allowing spaces for leakage to appear and the membrane becomes more permeable.

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