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

Investigation into the effect of temperature on the working of the enzyme amylase

Extracts from this document...

Introduction

Investigation into the effect of temperature on the working of the enzyme amylase Plan and Prediction The aim of this investigation is to find out how temperature affects the rate of reaction of the enzyme amylase, which is found in the salivary glands. Prediction My prediction is correct that at low temperatures the time taken for digestion will be slow as there is insufficient energy to make many molecules collide, at a higher temperature there will be more energy therefore more collisions and the reaction will be faster. The molecules have kinetic energy and as this increases so does their mobility, resulting in more collisions. I know that enzymes have optimum temperatures and the enzyme amylase should be 36.8`C- body temperature, so after about 40`C I think that more and more enzymes will be denatured due to the heat. When enzymes are denatured the active site's shape changes so that the substrates can no longer fit and so less and less reactions are able to occur. I have gathered much scientific knowledge that will help me decide how to plan my investigation. I know that amylase has an optimum working temperature, and this in theory would be body temperature as amylase is produced in the salivary glands and works in the mouth. It helps to digest starch and convert it into a simple sugar maltose. All enzymes are proteins and are therefore denatured by excessive heat. I know that a reaction can be affected by pH, concentration, amount of substrate/enzyme and temperature. Most enzymes work best at a pH of about 7, this is because they are all proteins and so are damaged by very acid or alkaline conditions. Rate of reaction and enzyme concentration are directly proportional; as enzyme concentration increases the rate of reaction gets faster. The effect of substrate concentration is different - when the amount of substrate is small the rate of reaction is low as there are few collisions; this steadily increases as the substrate increases but soon all the active sites on the enzymes are full so the rate of reaction stays the same. ...read more.

Middle

This showed that boiling salivary amylase denatures it, as the starch did not turn black using the boiled amylase. This experiment helped me with my prediction. Obtaining Evidence I have collected my results and managed to complete the experiment in the time allowed. During the experiment I made sure I was taking all the safety precautions I stated in "plan and prediction". Results: Temperature ('C) Time (secs) Colour Digested or not 10 30 Black X 10 60 Black X 10 90 Dark brown X 10 120 Dark brown X 10 150 Dark brown X 10 180 Brown X 10 210 Brown X 10 240 Orange ./ 18 30 Black X 18 60 Dark brown X 18 90 Dark brown X 18 120 Brown X 18 150 Brown X 18 180 Orange ./ 28 10 Black X 28 20 Black X 28 30 Black X 28 40 Dark brown X 28 50 Dark brown X 28 60 Dark brown X 28 70 Dark brown X 28 80 Dark brown X 28 90 Brown X 28 100 Brown X 28 110 Brown X 28 120 Brown X 28 130 Brown X 28 140 Brown/orange X 28 150 Orange ./ 40 10 Black X 40 20 Dark brown X 40 30 Dark brown X 40 40 Dark brown X 40 50 Brown X 40 60 Brown X 40 70 Brown X 40 80 Brown/orange X 40 90 Orange ./ 50 10 Black X 50 20 Dark brown X 50 30 Dark brown X 50 40 Dark brown X 50 50 Dark brown X 50 60 Brown X 50 70 Brown X 50 80 Brown X 50 90 Orange ./ 58 10 Black X 58 20 Dark brown X 58 30 Dark brown X 58 40 Brown X 58 50 Brown X 58 60 Orange ./ 70 10 Black X 70 20 Black X 70 30 Black X 70 40 Dark brown X 70 50 Dark brown X 70 60 Dark brown X 70 70 Dark brown X ...read more.

Conclusion

I think I could also improve the experiment by taking more result from within the range that I have chosen, as this would make the resulting best fit curve more accurate. I think my results could have been improved on by repeating the experiment once more and taking the average from that but from my graph I think that my results are accurate enough to back up my prediction. There are no results that do not fit my prediction suggesting that they are fairly accurate. Extension To extend and improve the work I have completed so far I could use actual human amylase because I think that the amylase we used for the experiment is not likely to have been actual human amylase but bacterial amylase. This would be good to find if the results are similar and show the same trend, if I was doing this experiment I would use the same method as I did for this one and include the improvements. It would be interesting to use amylase at varying time away from the last time the person's it was had eaten to find how this effected the results. For example, maybe just before a meal a person may have more amylase present in their saliva. Also I could find the exact optimum temperature by heating the starch and amylase to, for example 37 and doing the experiment, then 39, then 41, then 42 etc. Then when I found the temperature with the shortest reaction time I could do the experiment for the two temperatures above and below it, and find the optimum temperature from these three. I would then repeat this to make the results more accurate. Temperature (`C) Average time taken to digest the starch (secs) Calculation (1/time) Rate of reaction 10 240 1/240 0.00417 18 170 1/170 0.00588 28 135 1/135 0.00741 40 70 1/70 0.01429 50 80 1/80 0.01250 60 90 1/90 0.01112 68 145 1/145 0.00690 ?? ?? ?? ?? Catherine Lee L5B 1 ...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

    How does the concentration of enzymes affect the breakdown of starch by a-amylase in ...

    4 star(s)

    of the enzyme solution will, as I have said before, not be the limiting factor. I do not, however, know this as a fact, so I cannot come to any valid conclusion on whether the graph levels off or whether the graph keeps on increasing.

  2. Marked by a teacher

    How does the pH affect the activity of amylase

    3 star(s)

    to wait for it, so at times assumptions were made that the pH was correct, so I would say that it could have affect my results although conclusions were still able to be drawn. Most of the errors made were systematic once as it was to do with measuring solutions

  1. Marked by a teacher

    Beetroot Practical Write up

    3 star(s)

    Secondary source information to inform strategy: The previous testing on the effect of temperature showed that at higher temperatures more pigment was left in the solution.

  2. The Effect Of Temperature On The Action Of Salivary Amylase

    The same thing happens, when temperature increases the action of the enzyme increases as well. The optimum temperature of our enzyme is mostly around 370C. Almost every enzyme will be denatured above 600C, although some enzymes that live in hot spring will be denatured at 800C, which is suitable for their environment.

  1. Amylase is an enzyme that helps to digest starch into maltose

    * The same concentrations of starch and amylase will be used for each temperature and attempt. * The same amount of iodine will be used for each test for the presence of starch. * The test tubes and beakers will be all placed in the water-baths and ice-baths so all of their contents is warmed or cooled equally.

  2. 'Investigating how temperature affects the rate action of the amylase enzyme on starch.'

    * 1 Spotting Tile plate: (12 hollow spots) Contained in each of the hollow spots is one drop of iodine which is essential for the testing of the amylase-starch. * Glass Rod: This will be used for the purposes of testing. The glass rod will be first dipped into the test tube (which is in the beaker set at the allocated temperature)

  1. How does pH affect the Denaturation of enzymes Starch and Amylase.

    Method From deciding in my pilot study, before my experiment began, I set out a boiling tube with 5ml of starch and 5ml of alpha-amylase mixed. I added one drop of iodine and waited how for it to turn completely colourless.

  2. Investigating a factor that affects the rate starch is digested by Amylase.

    This is because there is clearly only one pH level at which you will get the shortest reaction time. Very few of the points fit exactly on the line of best fit marked on the graph. This is because of the three different trials of the experiment, all marked on the graph.

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