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

Inhibition of the decomposition of hydrogen peroxide by the catalase enzyme using copper sulphate.

Extracts from this document...


Inhibition of the decomposition of hydrogen peroxide by the catalase enzyme using copper sulphate. Hydrogen peroxide is broken down by the enzyme catalase into water and oxygen. Enzymes are catalysts that speed up the rate of metabolic reactions. These reactions can take place without the catalyst but take a considerably longer amount of time. Enzymes can either break down larger molecules into smaller molecules or build smaller molecules into larger ones. In the case of hydrogen peroxide, larger molecules are broken down. All enzymes are globular proteins held together hydrogen bonds, ionic bonds and disulphide bridges in a distinct three-dimensional shape and its shape is specific to each enzyme, as one substrate will fit only one active site. This is illustrated in the 'Lock and Key Hypothesis.' The lock and key hypothesis was to explain why enzymes are specific and will only work on particular substrates. The hypothesis tells us that the substrate fits the active site exactly and because every substrate is different each enzyme has an active site the correct shape for only one substrate and they have to fit each other exactly. ...read more.


High pH has a similar effect, but has an increase in Hydroxyl ions and this means both become negatively charged at repel each other. Some enzymes require cofactors before they can catalyse the reaction. Cofactors are non-protein molecules, which modify the chemical structure of the enzyme so it can function more effectively. Inhibitors: Inhibitors are substances that decrease the rate of reaction. This is achieved by the inhibitor binding with the enzyme and preventing it from forming and enzyme-substrate complex. Inhibitors can either be reversible or non-reversible. If an inhibitor is reversible the effect is only temporary and can be reversed when the inhibitor is removed. There are two types of reversible inhibitor; the competitive inhibitor and the non-competitive inhibitor. The competitive inhibitor has a similar structure to the substrate and is therefore able to bind with the active site. This decreases the number of active sites available to bind with the substrate, there fore decreasing the rate of reaction. Increasing the substrate concentration can decrease the effect of the inhibitor, as there is more substrate to compete for the active sites. The non-competitive inhibitor attaches to another part of the enzyme and its presence alters the overall structure of the enzyme, including the active site, therefore preventing the enzyme-substrate complex being formed. ...read more.


5. Repeat with other 5 samples. Results: Vegetable Volume of Hydrogen gas given off. (Cm3) Potato 8 8.5 Carrot 7 6 Swede 4 5 Parsnip 5 7.5 Errors: * The pipettes used to measure the volume of Hydrogen peroxide has an error of 0.05ml * The ruler used to measure the length of the potato has an error of 0.5mm. This is 0.5mm3 as the potato is a cylinder. * The gas syringe has an error of 5cm3 * The thermometer has an error of 0.05�c. When these errors are taken into consideration, the overall error is 5.1cm3. Vegetable Vol. of hydrogen gas (Cm3) Vol. Of Hydrogen gas (Cm3) Potato 8 - 13.1 8.5 - 13.6 Carrot 7 - 12.1 6 - 11.1 Swede 4 - 9.1 5 - 10.1 Parsnip 5 - 10.1 7.5 - 12.6 These results show that potato contains the highest level of the enzyme Catalase as potato gave off the highest volume of gas in a fixed amount of time, which tells me the rate of reaction is highest with potato as the catalyst. The potato is a catalyst because it naturally contains the enzyme Catalase. Therefore in my investigation to find the effects of different concen trations of the inhibitor copper sulphate I will use potato as the catalyst. ...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 Life Processes & 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 GCSE Life Processes & Cells essays

  1. Investagating the Action of the Enzyme Catalase On the Surface Area of a Potato.

    It takes a certain amount of catalase to decompose the substrate because of the active site in the catalase enzyme. EVALUATION: In this investigation, I should have timed the experiment less than ten minutes because it took too long for me to observe and conduct each set of results for

  2. What influence does pH have on the enzyme Catalase?

    This could affect the general trend of the data. Further data collection at this pH would make the data more reliable to base the conclusion on. On the other hand, some aspects of the data and investigation make it quite reliable.

  1. Biology catalyst couursework

    � 5ml (yeast) + 0ml (water) � 2% = 2% 4ml (yeast) � 4ml (yeast) + 1ml (water) � 2% = 1.6% 3ml (yeast) � 3ml (yeast) + 2ml (water) � 2% = 1.2% 2ml (yeast) � 2ml (yeast) + 3ml (water)

  2. A investigation into the effect of inhibitor concentration on the enzyme catalase.

    This also consists of two types: Competitive Inhibitor- These compete with the substrate for the active sites of enzyme molecule. The inhibitor may have a structure that permits it to combine with the active site. While it remains bound to the active site, it prevents a substrate molecule from occupying that site and so reduces the rate of reaction.

  1. My hypothesis is that the higher the concentration of hydrogen peroxide the more catalase ...

    Therefore the number of reactions per second decreases, and the reaction rate also decreases. Inhibitors may come from equipment that have been previously used and not cleaned and cross contamination. Enzyme activators bind to enzyme and increase the rate of reaction and therefore the number of reactions per second.

  2. Investigate the effect of the concentration of the enzyme catalase on the decomposition of ...

    This is shown on my predicted graph, the amount of oxygen stays the same after the experiment reaches a certain high concentration. Predicted graphs Preliminary plan The aim of my preliminary experiment is to test my method. I want to find out what volume of hydrogen peroxide I will need to use.

  1. The effect of hydrogen peroxide on catalase if you change the temperature.

    2.5 10 28.7 3 10 28.7 3.5 10 28.7 4 10 28.7 4.5 10 28.7 5 10 28.7 TEMPERATURE: 55�C TIME (mins) HEIGHT OF FROTHcm VOLUMEOF OXYGEN(cm�) 0.5 5.0 13.7 1 6.3 19.0 1.5 7.1 22.0 2 8.0 24.0 2.5 8.0 25.0 3 8.0 25.7 3.5 8.0 26.0 4 8.0

  2. Effects of Copper Sulphate on the rate of reaction between Trypsin and Milk Protein

    The test tube should then be slightly swirled in order to evenly distribute the components. A marker pen should be used to mark a cross on a plain white piece of paper approximately 5cm x 5cm. This cross should be held behind the test tube, it should not be visible

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