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

beetroot experiment

Extracts from this document...

Introduction

Why does the colour leak out of cooked Beetroot? Introduction: The purpose of this experiment is to investigate the effect of temperature on membrane structure and highlight experimental and investigative skills. Background Knowledge: Beetroot appears as a dark/red purple colour caused by betalain pigment which is contained within the vacuole of beetroot cells. In order for the betalain to leave the cell, it needs to pass through different membranes, the membrane bounding the vacuole and membrane enclosing the cell. Beetroot cells are quite unstable and will leak out when cut, heated, cooked, or when in contact with air or sunlight. This can also be showed and done by adding detergents and solvents as part of solution with the beetroot. Beta lain pigments are named after "beet" family of plants. Plant cells are quite different from other eukaryotic kingdom's organisms. Their distinctive features are: large central vacuole that maintains the cell's turgid and controls movements of molecules' cytosol and sap, of course chloroplast that contain chlorophyll which is the pigment that allows photosynthesis and more importantly the nucleus which controls the whole activity of the cell, also a wall made up of cellulose and protein deposited by protoplast on the outside of cell membrane. The plasma membrane is the inner layer of protection surrounded by rigid cell wall. The purpose of a cell membrane is to control the transport of substances moving into and out of the cell. The cell membrane is partially permeable due to its thin layer (7-10 nanometres) thick. It consists mostly of lipids and proteins the lipids found in cell membranes are triglycerides, have one molecule of glycerol chemically linked to 3 molecules of fatty acids, the majority being phospholipids. ...read more.

Middle

Place the cuvette into the colorimeter making sure that the light is shining through smooth glides. 8. Adjust the colorimeter to read 0 absorbance for clear water. Do not alter the setting again during the experiment. 9. Place 2 cm3 of the dye solution into a colorimeter cuvette and take reading for absorbency. Repeat readings for all the temperature. 10. Present your results in appropriate way. 11. Identify any trends or patterns in your results. 12. Explain any trends or patterns supporting your statements with evidence from your data and scientific knowledge. 13. Describe how you could have improved this experiment to give more reliable results. Results: A table of results to show Average light percentage absorbency of the dye solution in responds to the temperature and time taken. Temperature/�C Bath Temperature/�C Light Absorbency/% Average light Absorbency/% Time/minutes 1 2 0 1 0.33 0.28 0.31 34:55:5 10 20 0.06 0.03 0.05 33:33:6 20 19 0.03 0.02 0.03 32:51:6 30 31 0.04 0.03 0.07 30:48:4 40 40 0.08 0.08 0.08 29:14:6 50 49 0.48 0.26 0.37 28:03:7 60 60 1.85 1.75 1.80 27:14:3 70 68 2.00 1.80 1.90 25:32:3 A GRAPH TO SHOW THE AVERAGE LIGHT ABSORBENCY IN RESPOND TO THE TEMPERATURE INDICATED. Analysis: From the graph, the overall trend seems to be that as temperature increases, the percentage absorbency of the light absorbed increases gradually although there were points in the graph that didn't lie on the line of best fit. This is suggesting that membrane permeability decreases with temperature and gradually pigment leaks out. The darker the colour means more pigments have leaked out and higher percentage of absorbency is. As expected, the hottest temperatures were the deepest colour. ...read more.

Conclusion

To prevent this from happening, one good respond is to use more sensitive equipment or to get colorimeter checked because it could be broken and will result to equipment failure and false reading. Human error can be the biggest source of error as well. Because on some occasions, we didn't shake the boiling tubes with the equal efforts before we took the beetroot out and so could have been one of the reasons why the solution is darker or lighter than it should be. On inaccuracy that can be account to human error is the size of the beetroot. This could be explained by free hand sectioning because this would affect the surface area to volume ratio which in turn affects the diffusion. If the size was slightly smaller, it would have reduced the surface area therefore decreasing the amount of pigment leaked from the sample and makes the solution normal in respond to temperature. Another reason for the anomalies appearing could be due to the preparation sample. Many of the cells could have been damaged causing the pigment to leak during the experiment. A way of overcoming the inaccuracy of the measuring equipment used is to have rulers which are graded more accurately which may help to prevent inaccuracies occurring in the future. Possible additional work that can be done to rectify errors and would make the experiment much improved than it was before and could make findings more accurate are the following: using digital thermometers which can feed information on temperature continuously to a computer system would be ideal also, the experiment should be repeated more than two or three times and by doing so, it would be easier for me to work out clear average from wide numbers of range values in between results. ...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

    An investigation on the effect of temperature on beetroot membrane structure.

    4 star(s)

    Centre of beetroot appears to contain more betalain than the external parts. Beetroot washed in distilled water 10 minutes By using a stopwatch This is to ensure all betalains from damaged cells is washed away. Wavelength of light in colorimeter 470 nm To select wavelength of light an optic filter

  2. Marked by a teacher

    The Effect Of Temperature On The Permeability Of The Cell Membrane

    3 star(s)

    whereas the fatty acid tails cannot (hydrophobic). Preliminary Experiment A preliminary experiment will be carried out to assist in what pieces of equipment are essential to use in the experiment. The experiment will also assist in how long the beetroot should be left in the water.

  1. Marked by a teacher

    Effect of temperature on membranes

    3 star(s)

    and the help of carrier proteins to transport molecules across the membrane. Diffusion is the net movement of molecules from a region of higher concentration to a region of lower concentration down the concentration gradient until dynamic equilibrium is reached.

  2. The Endocrine System

    Hormones are sent to the posterior pituitary (the rear-most part) via nerves that run within the stalk. The posterior pituitary then stores and releases the hormones from the hypothalamus without making any hormones itself. For example, anti-diuretic hormone is produced by the hypothalamus, travels down through the nerves in

  1. The problem of rising deaths due to Malaria in Mumbai, India

    However, I don't think the results are reliable. This is because they were recorded 9 years ago, and with the rapidly progressing treatment for malaria, the opinions and figures may be out of date. Also there is no evidence of another scientist repeating the experiment and backing up the results, so for all we know the results could be made up.

  2. Role of blood in the body and experiment. The aim of this experiment is ...

    Red blood cells and haemoglobin The function of the red blood cells is to transport oxygen around the body. Oxygen is carried in red blood cells because it binds with a protein on the red blood cell. This protein is called haemoglobin.

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

    The cell membrane encloses a particle and buds off to form a food vacuole. Lysosomes with enzymes will fuse with it to enable digestion of the contents. Soluble products pass out of the vacuole and are assimilated. Pinocytosis: The ingestion of the fluid surrounding the cell is the process of pinocytosis.

  2. This experiment aims to investigate the effects of 4 different types of fish food ...

    Dependent Variables **** **** Dependent variables are affected by the independent variable, and are measured to see whether the independent variable has had an effect. Dry mass of the fry would be the most accurate way of measuring the growth of fry, however this would be both unethical and impractical,

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