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

Effect of Temperature on Membranes

Extracts from this document...

Introduction

SL Biology: Practical 5: Report Aim: to investigate the Effect of Temperature on Membranes Background: The colour of beetroot is due to the presence of a red pigment, betacyanin in the cell sap. As long as the cells and their membranes are intact, the betacyanine remains inside the vacuoles in the cells. However, if the membranes are stressed of damaged, betacyanin will leak through the membrane and produce a red colour in the water surrounding the beet tissue. Such stress or damage can be caused by heat. The intensity of this red colour will allow for the assessment of the damage produced by experimental treatment. Hypothesis: The higher the temperature, the higher the damage done to the cell membrane, and thus the more betacyanin released into the water surrounding the beet tissue. This will lead to a more intense shade of red. Materials, procedure: [as stated in practical] Variables: Dependent variables: the intensity of the redness in the water Independent variables: the 6 temperatures of water which the samples were submerged in Controlled variables: thickness of the discs (3mm), time span which discs are washed in water (5 min), volume of water in each test ...read more.

Middle

* The standard error is very small across the 2 samples for each temperature. This shows that the data is probably very accurate since it does not vary much. * From the graph, it is seen that there is a steady, consistent and linear increase in the absorbancy with increasing temperature. * This is in line with the background information which states that the higher the temperature, the more damaged the cell membrane gets. More betacyanin is released from the cell vacuoles, leading to a more intense shade of red, therefore resulting in a higher absorbancy. Thus, this supports the hypothesis. Evaluation * The results seem to be generally reliable, since they correspond with the understanding of how cell membranes are damaged by heat. * However, experimental errors could have occurred. For example, due to parallax error, it is difficult to ensure that all the discs are cut to exactly 3mm in diameter. Percentage error can occur in the variations of thickness of discs, leading to inaccurate amounts of betacyanin being released. This would affect the results since we are only looking at temperature as a cause of the higher amount of betacyanin released. ...read more.

Conclusion

The first one to be put in will also be the first one to be taken out. This will ensure that all the samples have the same amount of time for the betacyanin to be released and therefore ensure a more accurate result. * Instead of using a blade to cut the beetroot, a hard boiled egg cutter should be used. This can hold the beet root in place and ensure that each disc is consistent in its width. It is also swift and clean in cutting, ensuring that minimal cells are damaged, and even when there is damage done, it ensures that the extent of damage is same to each disc since many are cut at once. Moreover, being able to cut many at once is more efficient and reduces lag time. * The experiment would be extended to temperatures beyond 80 to find out the temperature at which all the betacyanin has leaked out and the absorbancy no longer increases due to increasing intensity of red. Conclusion * The hypothesis is proven true that as the temperature increases, the cell membranes get increasingly damaged and thus release larger amounts of the red pigment betacyanine, causing an increased intensity in the red of the surrounding water, thereby leading to a higher absorbancy. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Biology 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 International Baccalaureate Biology essays

  1. The effect on osmosis on the egg shell

    air cell that hampered fully immersion. Although some fluctuations were observed, the general trend (see Graphs 2-3) shows that due to salt concentration of the surrounding increase, the less is change in mass of an egg. According to Graph 1 and Table 5 illustrating mean results all of the measurements,

  2. The effect of toliet cleaning products on E-coli ...

    more effective than others. The most effective cleaner was the positive control of bleach. The products Duck, Harpic and home brand considering the standard deviation would fall largely in to the same range of effectiveness. King White however performed well above other toilet products and even rivalled the performance of

  1. Biology Extended Essay 2009

    In a normal endocrine system, blood sugar level, energy homeostasis and food intake are maintained mainly by the secretion of hormones known as insulin, leptin and ghrelin.30 Fructose, unlike glucose, doesn't trigger the pancreatic beta cell to secrete insulin into the blood.

  2. In this extended essay I am looking at the effect of different kind of ...

    * Cotton to provide moisture to the seeds. * 3 different kind of sounds/ noises (i.e. classical, rock, traffic- one from each category) * Measuring scale/ Ruler to measure the length of the plant. * Water to maintain the moisture * Speakers * 4 watch glass/ plastic plates * Headphone to protect your ears from high frequency sounds.

  1. What is the effect of different body positions i.e. lying down, sitting and standing ...

    62 7 84 55 8 117 68 9 142 87 10 64 49 Data Processing: Table 5: Average values for the systolic and diastolic (mmHg) pressure for participants standing up, sitting down and lying down Body position Systolic (mmHG) (�3mmHg)

  2. The aim of the investigation is to find out how an increase in surrounding ...

    cylinders the same as surface area is also a factor that effects the diffusion rate. * It is important to keep the control variable the same as it makes the experiment as fair as possible, in addition to this, you won't be able to know if the changes to the independent variable are causing the changes to the dependent variable.

  1. Beet Lab. Aim: To determine the effects of temperature on the permeability of ...

    Before starting the experiment, we should just wipe the apparatus to ensure zero error. 7. Do not overtime the experiment. 8. When the beetroot was cut some of the membrane was broken causing the pigment to leak out this must be thoroughly cleaned and washed off to secure the accuracy of results.

  2. The Effect of Alcohol on Biological Membranes

    ? No piece has any of the outer skin on it. ? All of the pieces are the same size. ? The pieces do not dry out. 8. Rinse the beet pieces several times using a small amount of water.

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