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

Investigating Respiration in Yeast

Extracts from this document...

Introduction

Investigating Respiration in Yeast Aim To investigate the effect of different concentrations of glucose on respiration in Yeast. Introduction Yeast Yeast is simply a single-celled fungus, found on the surface of fruit, feeding on sugar. Yeast can multiply itself by a process called budding. A large number can be formed in a short time. Respiration Respiration is basically the breakdown of glucose to feed a cell, supplying it with energy. There are two types of respiration: aerobic and anaerobic respiration. Aerobic respiration requires oxygen to carry out, but anaerobic respiration does not need oxygen. Anaerobic respiration causes lactic acid, which contributes to cramp. The equation of aerobic respiration is: Glucose + Oxygen --> Carbon Dioxide + Water + Energy C6H12O6 6O2 6CO2 6H2O Experiment We can measure respiration with a simple experiment - which is the one I am doing. We measure the volume of Carbon Dioxide with different glucose concentrations. This gives us our results. Variables I will measure the rate of Carbon Dioxide produced. This is the dependent variable. I will change the concentration of glucose. This is the independent variable. Other variables have to be controlled as these can also affect the reaction. ...read more.

Middle

50cm3 - 3 50cm3 - 4 50cm3 - 5 50cm3 - See graph on the next page Preliminary Conclusion I can conclude from this that respiration is a simple method including the breakdown of sugar unless the concentration of Yeast in the experiment has been made higher or lower. I have measured the change in Yeast in the above table and it has proved my Prediction. I am satisfied with my results but I believe I could have improved by: * Recording results twice for every concentration * Increasing the variety of concentrations for the experiment * Checking every piece of equipment that is clean before experiment Results 0% Concentration Glucose concn Volume of Water (H2O) in burette cm3 Volume of Carbon Dioxide (CO2) produced in cm3 Accumulative Volume cm3 Time 1 2 3 1 2 3 Avg 1 min 50cm 50cm 50cm 0cm 0cm 0cm 0cm 0cm 2 min 50cm 50cm 49cm 0cm 0cm 1cm 0cm 0cm 3 min 50cm 50cm 49cm 0cm 0cm 1cm 0cm 0cm 4 min 49cm 49cm 48cm 1cm 1cm 2cm 1cm 1cm 5 min 49cm 46cm 48cm 1cm 4cm 2cm 2cm 3cm 5% Concentration Glucose concn Volume of Water (H2O) ...read more.

Conclusion

This is not a problem, however. It is to be expected because each column of result was a different experiment. The suitability of the method was very good and clear and was easy to adhere to. There are only two seen improvements - by not being able to control the amount of agitation the yeast solution receives before the experiment may stop the validity of the experiment. The second improvement is that all the equipment should have been washed thoroughly beforehand so that no foreign germs may having effects while the experiment is taking place. To continue with the experiment, I had to make sure I had enough reliable evidence to make a prediction, a reliable experiment and a conclusion. I achieved this by trying a Preliminary Investigation before starting the main one. My hypothesis was correct and results were reliable evidence to suggest a larger experiment would be successful. I learned some safety precautions and method advances after the Preliminary Investigation to ensure a safe and valid experiment. Further work could have been tried to try to enhance the experiments legality. I could have used more experiments on the batch of Yeast to make sure that its contents were 100% pure. I could have used apparatus to agitate each sample of Yeast together so that they are identical to each other. Page 1 of 7 Darren Pinder 11T ...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

    Human Reproductive System

    4 star(s)

    Closostrum provides the baby immunity until it is able to develop its own. It is especially high in immunoglobulin A (IgA), which coats the lining of the baby's immature intestines and helps to prevent germs from invading the baby's system.

  2. To Investigate the Effect of Substrate Concentration On Yeast Respiration

    From these results, a graph can be plotted with concentration on the x-axis and the volume of gas released on the y-axis. To ensure this experiment is completed as fairly as possible, all the variables except for the concentration of Glucose must be kept the same for all experiments.

  1. Rate of Respiration

    This is due to the fact that sugars are needed in order to carry out respiration. Thus the yeast will be able to carry out aerobic and anaerobic respiration. Aerobic respiration will only occur on the surface of the yeast where oxygen is available; however anaerobic respiration will dominate the

  2. An investigation to see whether the concentration of Sucrose effects the amount of Carbon ...

    the surrounding atmosphere because the barrier between the two atmospheres is larger and hence harder to diffuse across. Diagram: Analysis: The graph does relate to the aim of the experiment because the aim of the experiment was to measure the rate of reaction by observing how much carbon dioxide was

  1. Investigate one factor that affects the rate of respiration of yeast

    This should help to minimize unreliable results. Whilst I am doing my experiment, I will note the results down on a table, in order to spot any obvious anomalies. The measurements themselves will be taken as carefully as possible. Time will be measured using the stop-watch (precise to �0.1 second),

  2. Rate of respiration in Yeast.

    down into a simple sugar before it can use it this will take time and it means that the glucose is more efficient at making the yeast respire. As yeast secretes enzymes from the cells to break down the food (sugars)

  1. Investigation into the effects of different

    * 5% yeast stock. * Distilled water * Glass stirrer * Stop clock * Balance * Pipette filler * Test tube rack x2 * Black marker * Weighing bottles * Rubber test tube lids x4 * Heamocytometry set * pH meter * Standard buffer solutions at pH 5 and 6. * Graduated transfer (plastic)

  2. Investigate the effect different concentrations of glucose in a yeast & Glucose solution has ...

    INPUT OUTPUT CONTROL VARIABLE Glucose Volume of CO2 Concentration of Yeast Stirring Temp Time pH How will each affect the experiment? In the next few lines I will explain each. pH - The pH will have to stay close to neutral (7)

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