Beetroot Experiment on temperature and Cell Membrane Permeability

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Beetroot Experiment on temperature and Cell Membrane Permeability

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    I have been asked to help a family friend with an A-Level Experiment conclusion. It is the experiment with beetroot pieces to find out how temperature affects cell membrane permeability. I know that as the temperature increases it increases the permeability and I think it is due to a permanent change in the protein structure part of the membrane (they become denatured), but am I right?? Thanks.
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     Hi, I did this excellent experiment recently teaching my AS level Biology students.  Your conclusion is correct, and I have added a few extra points that you & your family friend may find useful :

    •  Higher temperatures (for example, from 55 °C) increased the permeability of the tonoplast and plasma membrane
    •  The phospholipid bilayer could become progressively more disaggregated (increased kinetic energy of phospholipid molecules)
    • Membrane proteins could become denatured
    • Both could create extra holes for pigment leakage by diffusion – more leaky membranes and faster diffusion at higher temperatures
    •  Without the ability to control what goes in and out of cells, the control mechanisms in cells are disrupted, so they die.
    Enjoy Big Smile
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    Permeability increases well below 55C - you will see an increase from 0C upwards as the fluidity of the membrane increases.

    This is an experiment that can give good or rubbish results. Rubbish comes from:

    • using different beetroot for different samples
    • taking samples from different soil depths, they should be from the same circumference line
    • different depths of sample from the outside in

    At this time of year in particular, plants are changing their membrane make-up to acclimatize for winter which can affect results. Cells in different parts of the beetroot are changing at a different rate, so causing "noise" from the above effects.

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    Thanks : )
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