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

Anaerobic Respiration

Extracts from this document...


Energy In Food Introduction: Anaerobic Respiration The word anaerobic means 'in the absence of oxygen'. What is anaerobic Respiration? Anaerobic Respiration is the ability to obtain energy from food without the use of oxygen. Some organisms can survive for a long time without the supply of energy, i.e. Bacteria. They obtain their energy by an anaerobic process - called Anaerobic Respiration How can energy be released without oxygen? When oxygen is absent, the reactions produces less energy than normal, however it is still released from food by braking it down by chemically, and they produce carbon dioxide A common example of anaerobic respiration is within yeast, it is the action of yeast on sugar solution to produce alcohol. The sugar is not completely oxided to carbon dioxide and water but it is converted to alcohol. This process is called fermentation and is showed by the following equation: Enzymes C6H12O6 2C2H5OH + 2CO2 + 118 kJ glucose alcohol + Carbon + energy Dioxide The waste products of anaerobic respiration by yeast have been put to use for many hundreds, if not thousands, of years. ...read more.


There were many things that required adjustments and changes in my experiment as follows: I ensured that I used the same pieces of apparatus as much as I can throughout the whole experiment, to have a fairer test. As changing cans during an experiment, would probably alter results slightly, due to heat being taken into the boiling tube. I also made sure that the thermometers were checked and regularly changed throughout the experiment. As if I had used the same thermometer during the whole experiment the results would be inaccurate, as I would have to wait for the thermometer to reach the certain temperatures again. I made sure that I used the same amounts of yeast accurately, so that I could get the most accurate results. As if we had more or less water in the boiling tube than we should have, the results would obviously be affected, and the experiment would be very unfair. Upon looking back at the adjustments made, I believe that I am confident in saying that, I made sure that my experiment was as fair as I could possibly make it. ...read more.


I also found that the rate of respiration gradually increased, before it reached its greatest point (peak). Then it drops at a very rapid pace, to show the substances have reacted, and that the yeast has respired. The bubbles slowly continue to be put out, until the substances are totally used. My results seem to back up this proposal. Evaluation: My experiment in my opinion was performed at the best possible way it could be performed, but there were a few changes, which could have been made. The accuracy of the results was quite sufficient; however some of my results do seem peculiar. The reliability of my experiment was quite fair and supportive of my results. The results were as near enough as expected but there were a few anomalies which to alter the curve of the graph. To ensure this we could have possibly performed the experiment more times, for more tests. The depth of the delivery tube in the test tube could, to a certain extent, affect how many bubbles were released. Increasing the depth would make it harder for the bubbles to escape; as the pressure was so high. If the experiment were to be redone, I would have used different solutions in the other test tube. A certain possibility was limewater. ...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 Humans 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 Humans as Organisms essays

  1. Marked by a teacher

    Is the MMR vaccination safe?

    5 star(s)

    He concluded: "Current studies do not support the hypothesis that multiple vaccines overwhelm, weaken, or "use up" the immune system. On the contrary, young infants have an enormous capacity to respond to multiple vaccines, as well as to the many other challenges present in the environment" (19)

  2. Marked by a teacher

    The effect of different sugar substrates on the rate of yeast respiration

    4 star(s)

    I will use the gas syringe as it is an accurate piece of equipment and will help to gain accurate results. * Conical flask- this will be used to add the yeast and sugar, in order for the respiration of the yeast to take place.

  1. Marked by a teacher

    An investigation into the effect of temperature on the rate of respiration in yeast

    4 star(s)

    This will keep my results accurate. There are many possible causes of error that could affect my results: * If the yeast and glucose mixture is not the same temperature of the water. * If the temperature of the water bath (and hence the glucose and yeast mixture)

  2. Marked by a teacher

    How Does Temperature Affect the Rate of Respiration of Yeast?

    3 star(s)

    The glucose will be measured out each time using a measuring cylinder to make sure we have the same amount every time. AMOUNT OF SHAKING Shaking will help to activate the yeast. If it is not mixed properly the solution will take a long time to start the reaction and the results would not be fair.

  1. An experiment to investigate the rate of anaerobic respiration of yeast in various respiratory ...

    So, for 20 ml of pH7 buffer 1% yeast will equate to ([20/100]*1) = 0.2g of yeast. Similarly 2% respiratory substrate in 20ml pH7 buffer will equate to ([20/100]*2) = 0.4g respiratory substrate.0.2g yeast and 0.4g respiratory substrate in 20ml pH7 buffer will be used in all repeats for all sugars.

  2. Investigating the effect of temperature on yeast respiration.

    The experiments will have to be carried out more than just once, that will allow me to achieve raw data and processed data such as an average. It will be vitally important throughout the experiment that a fair test will be kept.

  1. Thistles by Ted Hughes. Question: Critically analyse the poem

    R : Furthermore, it seems as though thistles began and end with the presence of blood- spac'From the underground stain of a decayed Viking' they grow and before growing spac'grey like men', 'Everyone manages a plume of blood'. Hence, this parasite-like spacebehavior gives thistles an evil character for it thrives

  2. My aim is to find how temperature affects the rate of anaerobic respiration in ...

    * Air may become trapped between the oil and the yeast making the reaction aerobic. Bubbles: * The person could miss-count the bubbles. * The bubbles may be of different sizes. * Air may become trapped between the oil and the yeast making the reaction aerobic.

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