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

Action of the enzyme catalase.

Extracts from this document...

Introduction

Action of the enzyme catalase Aims: This is an experiment to examine the enzyme catalase, which living organisms contain this enzyme, how it acts on the substrate hydrogen peroxide, and how its activity changes in different pH conditions. Hypothesis: Enzymes such as catalase are protein molecules which are found in living cells. They are used to speed up specific reactions in the cells. Each enzyme just performs one particular reaction. Catalase is an enzyme found in food such as potato and liver. It is used for removing hydrogen peroxide from the cells. Hydrogen peroxide is the poisonous by-product of metabolism. Catalase speeds up the decomposition of hydrogen peroxide into water and oxygen as shown in the equations below. 2 H2O2 � 2 H2O + O2 It is able to speed up the decomposition of hydrogen peroxide 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 an anabolic reaction. ...read more.

Middle

the wooden splint caught fire 6. yellowish solution formed, no foam 7. lots of bubbles were formed, yellowish solution 8. yellowish solution formed with foam on the top Conclusion and evaluation: 1. Sand is the negative control because it does not contain the enzyme catalase. If any other materials act as the sand did (not producing bubbles, foam on the top of the solution), those materials do not contain catalase. 2. MnO2 does not contain the enzyme catalase because it is an inorganic compound. 3. Liver contains the enzyme catalase. Foam appeared as hydrogen peroxide was broken down to water and oxygen. 4. The temperature of H2O2 increased after the addition of liver because the breaking down of H2O2 is an exergonic reaction, that means that heat is produced during the reaction. 5. The H2O2 was broken down to H2O and O2, the glowing wooden splint caught fire due to the presence of the oxygen. ...read more.

Conclusion

When this saturation point is reached, then addision of extra substrate will make no difference. The rate steadily increases when more substrate is added because more of the active sites of the enzyme are being used which results in more reactions so the required amount of oxygen is made more quickly. Once the amount of substrate molecules added exceeds the number of active sites available then the rate of reaction will no longer go up, it will level off. This is because the maximum number of reactions are being done at once so any extra substrate molecules have to wait until some of the active sites become available. The enzyme activity exposed to different pH was compared only within the acidic and within the basic pH, however all the pH should have been compared. Fig. 2. Shows the effect of pH on enzyme activity. The optimum rate is between pH 3 and 12. Sources: http://medic.med.uth.tmc.edu/path/catalase.htm http://crystal.uah.edu/~carter/enzyme/catalase.htm http://neiljohan.com/projects/biology/enzymes.htm 1 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 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.

    produced as the surface area increased was less than what I should have gained allowing the results not to fit in with the line of best fit. These results do not seem as reliable as the other two sets. However, even in set 2, there are two results, which do

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

    The best model of enzyme function is imagining the enzyme active site to be a lock and the substrate to be a key. So, if the shape of the lock changes, then the key will no longer fit. This roughly reflects what happens when the active site changes, as the substrate molecule will no longer fit in it.

  1. The action of the catalyst on hydrogen peroxide

    Which means not as much oxygen will be produced as if the potato was fully covered by hydrogen peroxide. I could vary the solution of hydrogen peroxide. The weaker the solution of hydrogen peroxide, the less amount of oxygen

  2. Investigating the effect of temperature on the rate of enzyme action

    reaction at different temperatures In the experiment I plan to change only the temperature. All of the other variables will be kept the same so that the experiment is a fair test as to whether temperature affects the rate of enzyme action.

  1. Experiment to study the effect of Changing enzyme concentration on the rate of catalase ...

    > Effected by temperature - because they are proteins they are effected by temperatures above 40�C > Effected by Ph - they only work best at there optimum Ph, this is because they are proteins and damaged by very acidic or alkaline conditions.

  2. The Action of Enzymes

    the stomach have a very acidic optimum pH, due to the acidic conditions of the stomach, and enzymes found in the small intestine have an optimum pH of about 7.5. Here is a general graph for how the rate of reaction changes as the pH changes: Preliminary experiment To get

  1. Investigating Catalase.

    How enzymes work An enzyme is a biological catalyst, which is used to speed up the rate of a reaction so less energy is needed, and it is not used up in the reaction. Some enzymes facts: * Enzymes are large molecules * Each enzyme has its own special shape

  2. Structures and functions in living organisms. Revision Notes

    Contraction of the left ventricle forces blood through the aorta. Valves ensure that blood only flows in one direction http://1.bp.blogspot.com/_7l_-YD5MdrI/TB5fAiMCw1I/AAAAAAAAAB4/oGM-yqQ64DE/s1600/HumanHeartDiagram.jpg When a chamber of the heart is contracting, we say it is in systole; when a chamber is relaxing, we say it is in diastole 2.64 Understand that the heart

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