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

The Factors Effecting the Anaerobic Respiration of Yeast Cells

Extracts from this document...

Introduction

The Factors Effecting the Anaerobic Respiration of Yeast Cells Name: Joe Cox Set: 10A3 Form: 10H Control Variables; Ph - This is difficult to change and keep constant. That is why I did choose this variable to investigate. Concentration - This is reasonably simple to investigate. A lack of background knowledge of this subject prevented me from investigating this. Amount of Yeast - This is a reasonably simple variable to investigate but I don't think it would be in depth enough to write a good conclusion. All these variables must now be kept at a constant to make a fair test. Input Variable - Temperature This is the variable that I have chosen to investigate. It is simple enough but in depth enough to write a good conclusion. Background Information When yeast cells respire anaerobically the let off carbon dioxide off as a bi product of the respiration. This is less dense than water so it causes the beads to rise in water. This is the tester I use to see how the yeast cells are respiring. Prediction I predict that the warmer the solution then the faster the beads will rise. ...read more.

Middle

When filling up beakers and boiling tubes we must be extremely careful in order not to burn ourselves. The yeast cells can also be irritable if they get in eyes, so some care must be taken when using these cells. Diagram Results Temperature How long (1st) How many after ten minutes? Average Room (21�) 26.47 0 26.421/2 seconds 26.38 0 30� 10.45 0 10.321/2 seconds 10.20 0 40� 6.05 10 6.121/2 seconds 6.20 10 45� 4.30 10 5.01 9 50� 5.15 10 5.21 seconds 5.27 10 60� 30 + minutes 0 No average 30 + minutes 0 Analysis From my results you can see that the basic relationship is that as the temperature gets higher it takes less time for the beads to rise. The graph shows the relationship as a negative correlation. The graph is not a straight line; this is because the temperature does not increase at a proportional rate to the time taken for the yeast balls to rise. This is explained in the conclusion. The graph dips at 45� and then goes up again afterwards. For the basic results it does not prove or disprove my prediction. ...read more.

Conclusion

A problem with my prediction is that it stated that at forty degrees the cells would denature but the results and graph showed that the cells denatured at 45 degrees C. This is what the dip in the graph has shown. This could be for various reasons, the most likely reason is that the cells did not actually experience temperatures of those stated. The water in the water bath would lose heat before it reached the beads, this is due to temperature travelling through the glass and losing heat energy on the way. An alternative explanation for this is the beads were not subject to these temperatures because they were insulated by other beads surrounding them. The added test of the beads at 45�C was a very beneficial us. It enabled us to find out the optimum temperature that the beads respired at. It also enabled us to work out the temperature at which the beads denatured; this was a temperature around the 45�C area. We cannot say for sure due to the cooling baths losing heat energy and the insulating properties of the beads. Up to the forty five-degree point the yeast balls respired more efficiently at a higher temperature, this was due to the increased energy the particles were given. My prediction was proved mainly correct. ...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

    The Effect Of Temperature on the Respiration Of Yeast.

    5 star(s)

    this is what I am testing to see its effect on the respiration of yeast. I am going to vary this by using a Bunsen burner to change the temperature of the water and a polystyrene cup to insulate the heat.

  2. Marked by a teacher

    Investigating respiration of maggots

    5 star(s)

    maggots will consume air- therefore respiring aerobically, and this will cause the bubble to be pushed towards the maggots. If at times they respire without oxygen- i.e. anaerobic respiration- the rate of oxygen uptake will be affected and will give inaccurate results.

  1. Affect of sucrose concentration on the rate of respiration.

    Here it will be kept at this temperature through out the experiment. The pH of the solution will also be constant at a pH of 7. This will be achieved by using a buffer solution. The stopwatch will be used in order to ensure accurate timing and that one experiment is not left longer than stated which is 3mins.

  2. Investigate how temperature affects the rate of anaerobic respiration in a sucrose & yeast ...

    than the inaccurate method of counting bubbles (we do not, in fact, know the size of the bubbles or whether this size is consistent throughout the tests). One of the factors that affected our results that is more difficult to control is the change of temperature of the water bath during the experiments.

  1. Investigating the Effect of Temperature on Rate of Respiration in Yeast

    We would have to stop the stop clock at a certain colour of TTC. Trying to remember and stop the stop clock at a certain point is probably impossible by the naked eye. Even a colorimeter cannot be used. So TTC is not a very good indicator to use.

  2. The factors that affect the respiration of immobilised yeast

    For fermentation of occur, yeast requires a source of carbohydrates, anaerobic conditions and a suitable temperature. Fermentation stops when the yeast becomes poisoned by its own waste, the alcohol, which acts as a non competitive inhibitor to the enzymes involved in the process.

  1. Daphnia write up

    The fact that higher concentrations of caffeine caused the heart rate of the Daphnia to decrease supports the reasoning behind using caffeine as a pesticide. Although my results did show a trend, they also included a set of anomalous results, or outliers. This occurred at the caffeine concentration of 0.2%.

  2. Investigation to discover the effect of temperature on anaerobic respiration in yeast cells.

    Yeast can respire using oxygen, this is known as aerobic respiration and releases up to 20 times more energy that fermentation or anaerobic respiration. However the investigation that I wish to proceed with does not require aerobic respiration, therefore I will coat the surface of the yeast solution with a

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