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

Experiment to show the factors that effect the respiration in yeast

Extracts from this document...


Experiment to show the factors that effect the respiration in yeast Introduction Yeast is a single celled fungus. It respires anaerobically (the release of energy from glucose, without combining it with oxygen). When this is done it converts sugar to ethanol. Yeast is one of the living cells which can respire without oxygen anaerobically by reacting with a sugar solution such as glucose to produce carbon dioxide and ethanol and a small amount of energy. When the conversion of sugar to ethanol and carbon dioxide it is known as fermentation. The energy formed is necessary for the yeast to carry out the reactions necessary for cell growth. Yeast cell replicates fastest at about forty-two degrees Celsius. The variable I have used to carry out this experiment is Temperature Equation: Glucose -> alcohol + carbon dioxide + energy Prediction I predict that in my bubble count the number of bubbles will increase gradually as the temperature increase up to sixty-two degrees Celsius because the yeast will respire faster at a higher temperature. At 27 degrees Celsius the yeast will give off Carbon dioxide because the temperature is to low and it is not high enough to form a reaction but between 32 degrees Celsius and 47 degrees Celsius a large amount of Carbon Dioxide we be given off. ...read more.


After that you connect the delivery tube to the boiling tube with the rubber bung going into the boiling tube and the glass end going into a test tube. 8. You then start your stop clock and leave it running for 10minutes waiting for the yeast and glucose solution to react and form carbon dioxide which should then form bubbles. 9. You then count the amount of bubbles formed within one minute. 10. When you have completed those following steps you repeated them three times for each temperature. You use these eight different temperatures which are: 27, 32, 37, 42, 47, 52, 57, & 62 degrees Celsius. Diagram to show the method used Results Temperature (degrees Celsius) Carbon Dioxide Bubbles within one minute 1 2 3 Average 27 4 4 5 9.67 32 9 10 10 22.33 37 22 24 25 54.33 42 44 47 48 107.00 47 63 67 70 153.33 52 15 14 17 15.33 57 13 11 14 12.6 62 No Bubbles formed 0 Conclusion Hydrogen Peroxide is broken down by peroxides in many organisms. Its catalytic results in the release of oxygen gas can be collected and is measured. The estimation of the oxygen release can be made by counting bubbles. Equation: 2H2O2 --> 2H2O + O2 Hydrogen Peroxide The experiment uses the peroxides of yeast which is available without destruction of yeast cells. ...read more.


The second to last temperature I tested was 57 degrees Celsius. At this point very few bubbles were formed. The amounts of bubbles formed were similar to the amounts formed at 32 degrees Celsius. The last temperature I tested was 62 degrees Celsius. At this point there were no bubbles formed therefore the yeast had denatured. Evaluation My results may not have been accurate as they should have been because sometimes the amount of bubbles being let of may have been released to fast and therefore they could not have been counted correctly and accurately. Different batches of yeast which were used gave of different results in my experiment. The bubbles which were formed could have either been large or small, therefore the accuracy of my results may have reduced. The Temperature of the climate outside can make my results vary. At different times of the day you can get different results because of the room temperature changing. e.g. Monday morning the experiment takes place, the room temperature is colder. Thursday afternoon the experiment continues, the room temperature is a lot warmer than the Monday morning. The Timings of the experiment done can also effect my results because at different times of the day, the temperature of the yeast can be affected. This shows that errors have occurred. All of the reasons given above evaluate what problems went wrong during my experiment. ?? ?? ?? ?? Rishul Shah 10B ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Green Plants as Organisms 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 GCSE Green Plants as Organisms essays

  1. The effect temperature has on the rate of anaerobic respiration in yeast.

    enzymes start to denature and they no longer have a use because the substrate doesn't fit in the enzyme. Evaluation: I ensures safety in the experiment by using goggles to protect my eyes and rubber gloves to protect my hands from the heat of the water when I held the syringe underneath the water.

  2. Investigating the Factors Affecting Respiration in Yeast.

    Next, we place a plastic tube on the nozzle of the syringe and do either of the following: * The carbon dioxide produced will push out of the plastic tube on the nozzle of the syringe. We can count how many bubbles are produced within a given period of time.

  1. What is the effect on the rate of respiration of yeast cells with glucose ...

    4 24 6 35 8 48 10 60 Prediction based on the results of the preliminary experiment I predict that the temperature of the yeast will affect its rate of respiration because enzymes are involved. I predict that the optimum temperature for the respiration of yeast cells is between 35�C and 40�C.

  2. Investigation of the effect of glucose concentration on anaerobic respiration in yeast.

    The concentration of a solution can speed up or slow down the rate of respiration depending on how concentrated the solution is. In the case of my experiment, the strongest concentration speeded up the rate of respiration while the weakest concentration was very slow in producing carbon dioxide thus, showing that the rate of respiration was much slower.

  1. Investigating the effect of concentration of sugar on the respiration rate of yeast

    The high concentration of ethanol produced as a by-product. 2. The temperature of the reaction, as some of the energy produced converts into heat energy. At really high temperatures the reaction will stop because the heat will have denatured the enzymes.

  2. Experiment to investigate the effect of temperature on respiration in yeast.

    The thing that didn't seem to fit which happened in both cases of my experiments was that once the temperature had reached 62 % (which was the end of the respiration) it didn't have any bubbles then when it reached about 70 % it produced a bubbles I think this

  1. Investigating The Fermentation of Yeast

    Next, I shall repeat the experiment a number of times using a mixture which is starts at higher temperatures and see what effect this has on things. Each time I do the experiment I am going to use two test tubes of mixture to try to even out any odd things that might happen.

  2. catalase and hydrgen peroxide

    * Heart will react faster and oxygen bubble production per minute will be twice of that than the aubergine. * The amount of oxygen produced by the aubergine will increase when it is crushed, as the surface area is greater.

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