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

Enzyme Investigation.

Extracts from this document...


Enzyme Investigation Enzymes such as Catalase are protein molecules, which are found in living cells. They are used to speed up specific reactions within the cell. They are all very specific as each enzyme just performs one particular reaction. Catalase is an enzyme found in food such as potato and liver. It is used to remove Hydrogen Peroxide from cells. Catalase speeds up the decomposition of Hydrogen Peroxide into water and oxygen because the shape of its active site matches the shape of the Hydrogen peroxide molecule. This type of reaction where a molecule is broken down into smaller pieces is called a catabolic reaction. This is the reaction equation for the breakdown of hydrogen peroxide into water and oxygen: Hydrogen Peroxide + Catalase = Water + Oxygen. 2H202 2H20 + 02 Aim: The aim of this experiment was to examine the effect of catalase on the breakdown of the substrate hydrogen peroxide. The catalase used was obtained from a piece of liver. An enzyme is a biological catalyst. Catalysts speed up reactions. Most enzymes optimum working temperature is 37 (body temperature), however the optimum working temperature of catalase is 30 . ...read more.


With more successful collisions with more energy, the amount of oxygen should be produced at a faster rate, which is how the graph has turned out. The graph more or less resembles my predicted graph and my prediction. Looking at the graph I will explain why the set temperatures on the graph are correct or not. 18 C -The line of best fit produced fits in with my prediction and the theories stated on the previous pages. Whilst the optimum temperature of a catalase is higher than that of room temperature (app 20 C), this shows that oxygen has been given off at an acceptable rate at room temperature. There was enough successful collisions and energy to produce oxygen from the reaction, so is not regarded as an anomalous result. 33 C - In my opinion I would regard this scatter as anomalous. This is because it does not tie in with the rate of reaction theory. 33C is near an enzymes optimum temperature and so should produce more oxygen in a shorter space of time, but this is not the case. This could have been due to a recording error or a disruption to the independent variables. ...read more.


Obviously, the experiment could have been improved by repeating the experiment more times to calculate a better average. I think there was sufficient evidence to draw firm conclusions from the results as it agreed with my prediction and proves many of the reaction theories. Many variations of this experiment could back up the evidence I already have. The independent variables could be changed. For instance: the hydrogen peroxide concentration, differently shaped sizes of the liver and surface area. How much enzyme is in 1 gram of liver is questionable. The same weight doesn't truly determine the same amount of enzyme contained in the liver. So if a piece of the liver was collected from the centre of the liver it may contain more or less enzyme than the edge or vice verse. It may even contain the same amount of enzyme all over. The liver was probably kept over a series of days and this would of affected the amount of water in the liver. If the water evaporated the catalase would be in a dehydrated state. This would mean that the weight may stay the same or decrease and the amount of enzyme would also increase or decrease. To overcome this problem, it would be wise to dehydrate all the liver or keep the whole of the liver moist. By Arun Joshi ...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

    "To Clone or Not to Clone- That is the Question".

    4 star(s)

    The public accumulated a riot, as the notions got wilder and wilder. The leap from cloning a sheep to cloning humans is indeed a great one scientifically, yet scientists are still making plans. A ban was proposed on the funds of its further research in the US until the issues

  2. Investigate how concentration of the enzyme catalase in celery tissue alters the rate of ...

    For this to occur the catalase molecule must collide with the Hydrogen Peroxide molecule at the correct orientation to each other and the reacting molecules must haven enough energy to bring about the breakage of chemical bonds. Enzymes overcome the need for larger amounts of energy because it decreases the amount of energy needed.

  1. Catalyse Investigation

    but it may not be the case. The science on which the prediction is based, however, seems sound to me although I don't I doubt that there are complications which I haven't thought of yet. It is therefore feasible that the Q 10 formula worked and that the other set of results is correct.

  2. An investigation to see how different concentrations of aspirin affects hydrogen peroxide breakdown by ...

    If touched: Wash skin immediately with water. If ingested: Dilute with ample water. Inform teacher immediately. Test Tubes Made of glass which can be dangerous. I will avoid breaking any of the test tubes, and will not use any chipped glassware.

  1. This is an experiment to show how different concentration of celery tissue enzyme, catalase ...

    This means large amount of hydrogen peroxide will be broken down. Consequently, as the enzymes breakdown hydrogen peroxide there will be little left of this substrate, resulting in the high amount of oxygen. I think if the enzyme concentration is doubled from 25% to 50% concentration the amount o oxygen produced will also double.

  2. An Investigation to determine the effect of Substrate Concentration on the Enzyme Catalase

    As shown by this graph, the optimum pH at which enzymes work best in, vary from enzyme to enzyme. When the pH changes from the optimum, the shape of the enzyme changes and the affinity of the substrate for the active site decreases.

  1. An Investigation on the Effect of Enzyme Concentration on rate of hydrogen peroxide breakdown.

    The enzyme itself is not altered in any way and is therefore ready to receive another substrate molecule/s. The diagram below shows the action of enzymes. * Activation energy Enzymes are catalysts and increase the rate of reaction by lowering the activation energy of the reaction.

  2. Amylase Investigation

    Figure 7. Substrate inhibition will sometimes occur when excessive amounts of substrate are present. Figure 8 shows the reaction velocity decreasing after the maximum velocity has been reached. Additional amounts of substrate added to the reaction mixture after this point actually decreases the reaction rate.

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