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

For this practical I will see how temperature affects the rate of respiration with yeast. To do this I will conduct an experiment which will test this in the most fair and safe way.

Extracts from this document...

Introduction

Biology Practical Assessment Coursework Planning For this practical I will see how temperature affects the rate of respiration with yeast. To do this I will conduct an experiment which will test this in the most fair and safe way. My prediction for the experiment is that the yeast will respirate the most carbon dioxide at 40*C this is because yeast is an enzyme and we have enzymes in our body and they work best at our core body temperature which is 37*C. Yeast is a single celled organism and it uses sugar that is needed to react with the oxygen these react to respirate which produces three products; carbon dioxide, water and energy but to do this the molecules must collide. The molecules at different temperatures will have various collision rates this is how at which temperature the yeast will respirate best at. The higher the temperature the more collisions will occur which will increase the reaction rate so the yeast will respirate at higher rate but only to a certain point because if the temperature is too high the enzymes begin to naturise and don't work properly so the rate of respiration will begin to drop. ...read more.

Middle

- after the practical has been finished mark results into the results table and see if there are any anomalies and confirm if you wish to do any of the temperatures again but only if there is time. Results These where the results that we got from the practical. Water displaced with Carbon dioxide in cm3 Temperature in *C First test Second test 30 5 5 40 11 10.5 50 15.5 14.5 60 9.5 8 70 2.5 2 All of these results followed a pattern apart from one which is the most of the trend by 1.5 mm3 which is at 60*C on the second test but it isn't an extreme anomaly. The averages are; 30*C = 5 40*C = 10.75 50*C = 15 60*C = 8.75 70*C = 2.25 My results show that at 50*C the enzymes worked best. At 30*C the enzymes respired at quite a slow rate but then at 40*C the respiration rate increased by double this is because there was more heat so more kinetic energy was gained allowing a higher rate of collisions to occur so an increase in reaction speed. At 50*C the most amount of water was displaced by carbon dioxide this follow the same reason as before accept that the molecules were moving even faster. ...read more.

Conclusion

I feel that the results were accurate as we didn't have any anomalies and the results from both test were similar and were as far as 1cm3 off apart from one which was 1.5cm3 off so we noted that as a half anomaly but we found it as not much of an interest also the results repeated ach other as well. We as a group didn't come to any problems and neither did I with the practical technique but there was a problem which wouldn't have been any easy to resolve and that was then tome available basically perfect timing and organisation would have helped with that but then there was the other groups to wait for. If there any ways to improve the experiment it would be to ask for more time so we can do the experiment a few more times for more reliable result to work with and if any serious mistakes were made there would be time to recover from them. If we had more time we could also have extended the practical by maybe seeing if the strength of the solution would change the amount of carbon dioxide released and if other solution that were to be mixed in would make a difference. ...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)

    Then I will start the stop clock. While the experiment is taking place I will observe the temperature of the water if there is a drop, even though I am using a polystyrene cup as an insulator, there will still be a temperature drop when the experiment takes long for example at 25oC.

  2. Marked by a teacher

    Investigating respiration of maggots

    5 star(s)

    The reason for using a 1cm3 syringe as oppose to a 10cm3 syringe is because it has a smaller error margin, and therefore makes it more accurate to use. - Thermometer I am using a thermometer to ensure that the temperature of the water bath remains constant throughout.

  1. Marked by a teacher

    Beetroot Practical Write up

    3 star(s)

    time in one experiment and then at a shorter time the next, would not be considered accurate or constant. With the beetroot in at a longer length of time eventually the ethanol would have totally destroyed the cell membrane whatever the size of the beetroot or ratio with distilled water.

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

    I will then immediately place a bung over the test tube and invert it twice. After inverting it I will remove the bung and place the test tube carefully back into the beaker. I will then start the analogue stop-watch.

  1. The rate of respiration in yeast and how it is affected by temperature.

    a list of variables that can have an affect on my experiment and also how I will control them if possible: * Temperature * Amount of yeast * Amount of glucose * Volume of water TEMPERATURE Temperature of the experiment will have a great affect on the results as explained by kinetic theory.

  2. ENZYMES COURSEWORK

    Continue until 60cm3, as this will provide you with a wide range of varying results that can help you draw to a correct conclusion. Conclusion By looking at the results in the table above, I have come to the same result as my hypothesis.

  1. Biology - Enzymes: Written Account of Practical Assessment

    In this example, enzymes are like the auto assembly line. Just like the enzyme, the assembly line helps convert individual auto parts into a complete auto, and as the completed car leaves, they begin to build a new auto. The more assembly lines the less time it takes to crank the cars I.e.

  2. Experiment to Show the Respiration Rate in Yeast

    At 20?C the yeast rose to 50cm�, but at 40?C it rose to 80cm�. This proves that at higher temperatures the yeast respires quicker and therefore rises faster. However there is not enough evidence to prove my theory of the optimum heat capacity and proof of the enzymes becoming denatured.

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