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

Investigating the effect of enzyme activity

Extracts from this document...


Investigating the effect of enzyme activity Aim: Almost all chemical reactions that occur in living organisms are catalyzed by enzymes. The aim of this experiment is to investigate the breakdown of starch molecules (polysaccharides) into maltose molecules (disaccharides) catalyzed by the digestive enzyme amylase. Many factors in a cell's environment effect the action of an enzyme. The experiment of the effect of temperature on the enzyme amylase was performed to determine the correlation between the two. It was developed to test the enzymes reaction rate of digesting starch when it was unheated and after it had been heated. Hypothesis: Iodine and starch react to produce a dark blue colour so iodine may be used as an indicator to show the rate at which starch is broken down. By mixing the starch solution with the enzyme solution, (which we collected from our spit, that contains the enzyme amylase) the enzymes will slowly digest the starch to smaller units (maltose), and the iodine solution will turn yellow/brown. I know for a fact that most enzymes thrive best at a temperature around 40 �C, and around 45 �C they will start to be damaged. So therefore I predict: the amylase enzymes in our enzyme solution will not be able to break down the starch in our starch solution after having been heated, and therefore the iodine solution will remain dark blue. ...read more.


like for example amylase. After being chewed and swallowed, the food enters the esophagus on its way to the stomach. After being in the stomach, food enters the small intestine. In the small intestine, bile (produced in the liver and stored in the gall bladder), pancreatic enzymes, and other digestive enzymes produced by the inner wall of the small intestine help in the breakdown of food. Rate of enzyme activity Enzyme activity is affected by several factors such as temperature, pH, the concentration of the substrate or of the enzyme, and sometimes even stress. However, the factor which we are testing in this experiment is temperature. Enzyme activity is changed by variation in temperature. As temperature rises the rate of chemical reactions increases because temperature increases the rate of motion of molecules. This leads to more interactions between an enzyme and its substrate. In this experiment the substrate was starch, which is a polysaccharide of glucose. However, if the temperature is too high, enzymes can be denatured and they can no longer bind to a substrate and catalyze reactions. In other words: the enzyme activity will increase as the temperature rises, until a certain high temperature at which the enzyme will denature and be non-functional. ...read more.


6. Afterwards we mixed 1 ml of the enzyme solution with 5 ml of the starch solution, and added a drop of the mixture into a hollow in the porcelain plate. Immediately we added a drop of the iodine solution. We made a sample every 20 second until the samples turned yellow/brown and noted the time. 7. Then we repeated everything from the step number 6, but instead of using the unheated enzyme solution we used the heated. Results: Discussion: Looking at the data collected, it appears as though the hypothesis which was developed at the beginning of the experiment was in fact correct. The amylase from our spit did breakdown the starch in the starch solution, and after 80 seconds the colour of the iodine solution went from being dark blue to yellow/brown. And as mentioned in the hypothesis the colour of the iodine solution stayed dark blue after the enzyme solution had been heated. Conclusion: In conclusion this experiment further confirmed that enzymes are damaged at a temperature above 60 �C. Each enzyme has its own individual prime functional temperature, therefore if they are removed from these environments they will not function as well or possibly denature if it the temperature is too high. Although, if an enzyme's optimal temperature is maintained then the enzymes will catalyze reactions at optimum rates. ?? ?? ?? ?? Malaz 1i 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 International Baccalaureate Biology 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 International Baccalaureate Biology essays

  1. Marked by a teacher

    The effect of temperature on amylase activity

    4 star(s)

    constant The stable temperature can ensure a stable reaction in the amylase and starch mixture, a more reliable result will be introduced Method 1 Use a syringe to pump amylase into one test tube and starch solution into another. 2 Place the two tubes to equilibrate for 5 min.

  2. Marked by a teacher

    The Effect of Temperature on Enzymatic Activity. Aim To investigate enzyme activity ...

    3 star(s)

    Conclusion In conclusion my hypothesis was correct because the rate or enzymatic activity did increase to a point and then dropped. This is due to the enzymes having an optimum temperature at which they catalyze reactions most efficiently. It can be seen that the optimum level for enzymatic activity is

  1. Browning Enzyme

    After 17 minutes have passed, one by one decant the bathing liquid from each and every test tube into the crucible and crush the disc. After one disc has been crushed put it into the filter paper and wait for the solution to drip into the test tube.

  2. An experiment to investigate the action of saliva on starch:

    Rinse mouth with 20cm3 of distilled water: spit this back into the sink. 3) Rinse mouth a second time with 20cm3 of distilled water. This time keep the water in the mouth for 30 seconds, moving it around with the tongue. Collect this diluted saliva in a beaker. 4)

  1. Investigating an enzyme-controlled reaction: catalase and hydrogen peroxide concentration

    As a precaution, I have limited my contact with the boiling tubes, as my body heat will raise the temperature, increasing the rate of reaction or expanding the gas inside the test tube moving the manometer fluid. I also monitored the temperature using a thermometer to ensure that it remained

  2. Enzyme activity using the enzyme catalase in different plant sources

    Fill the kettle with water and turn on 7) Then pour water into a beaker to make the water bath 8) Add ice to regulate the temperature to 37oC 9) Add the food samples each into a different test tubes 10) Put the test tubes into the water bath 11)

  1. In this extended essay I am looking at the effect of different kind of ...

    each plant every day and you will also observe that, with days the number of branches in the plant increases. If you will not take your of your plant properly your plant will bend and will die soon. So give support to plants when required.

  2. Testing the effect of characteristics of leaves on the transpiration rate of * ...

    Other than wind, the conditions of light, humidity, and temperature would be very different from day 1 to day 2. The experiment on day 1 was in the noon when the temperature was high and humidity was low.

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