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

Find out if different concentrations of catalase (in this case yeast suspension) change the rate of reaction.

Extracts from this document...

Introduction

Seb Jenner 10A Catalase Investigation The aim of this investigation is to find out if different concentrations of catalase (in this case yeast suspension) change the rate of reaction. We are using yeast suspension as the catalase because it is very easy to use and it is the most reactive out of the ones that we tested. Enzymes are made up of protein molecules, they are also catalysts, this means that they speed up biological reactions. Each type of enzyme can only speed up one kind of reaction, this is because each enzyme's active site is a different shape and so it can only speed up the reaction of the molecule with the complementary shape. (AQA GCSE Science) Catalase is found in every cell, it is needed because hydrogen peroxide is poisonous, the catalase reacts with it to divide it into water and oxygen. This is a diagram of catalase: Catalase increases the reaction rate of the decomposition of Hydrogen Peroxide into water and oxygen. This equation shows this: Catalase Hydrogen Peroxide---------------------->Water + Oxygen Catalase 2H2O2 ------------------->2H2O+O2 This is a diagram showing how substrates fit together with enzymes into the active site (borrowed from John Grantham) ...read more.

Middle

Apparatus * 1 boiling tube * 1 measuring cylinder * 1 delivery tube * 2 syringes (1cm3) * 1 beaker * yeast solution (5 %) * hydrogen peroxide (10%) * Bung * Needle My preliminary experiment showed me that I should use 1cm3 of yeast and 1cm of hydrogen peroxide, this was because they were very reactive and also because if I used more than 1cm3too much oxygen would be displaced. It also showed me that yeast solution was the best catalase to use because it produced the most froth, meaning it had a higher reaction rate. The preliminary experiment also gave me a chance to get accustomed to the equipment that I would be using in our investigation. I plan on recording the increase in oxygen by recording the decrease in water in the measuring cylinder. I will record my results every five seconds up to thirty seconds. Method * Put 1cm3 of hydrogen peroxide in test tube. * Put the bung (attached to the delivery tube) on the test tube. * Place the delivery tube in a beaker of water. * Place a measuring cylinder filled with water over the delivery tube. ...read more.

Conclusion

of yeast % 5 seconds 10 Seconds 15 seconds 20 seconds 5 3 5.5 7.5 10 4 1.5 3 5 7.25 3 1 1.75 4 5.5 2 1 1 2.5 4 1 0.25 0.75 1 2 0 0 0 0 0 The Graph on the next page and the results above show that the greater the concentration of catalase, the more oxygen is produced in a shorter space of time. This is because there are more catalase molecules and so more collisions, therefore the Hydrogen Peroxide molecules can be broken down faster too Oxygen and water. One thing that I would have expected to see was a limit in the speed that the reaction occurred with the different concentrations. I obviously should have continued my experiment to achieve these results. I believe that my results were fairly accurate, however to improve them I could have repeated the experiment, and continued for more than 20 seconds. A problem that I could not overcome was the reliability of the human eye. I may have misread the volume on the measuring cylinder, however without expensive machinery I could not achieve perfection. ...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. Investigate how concentration of the enzyme catalase in celery tissue alters the rate of ...

    Increasing the enzyme concentration increased the amount of gas produced because this increased the probability of successful collisions with Hydrogen Peroxide molecule producing more water and oxygen gas at a quicker rate. There is not an unlimited supply of substrate molecules so all reactions would have reached a maximum velocity.

  2. Applied Science

    Decomposition reactions cause all catabolic process that occurs in body cells. For example, the bonds of glycogen molecules are broken to release simpler molecules of glucose sugar. In the group of catabolic reactions collective called cellular respiration, food fuels particularly glucose are broken down in cells and some of the

  1. To find out how different concentrations of sucrose solution affect the incipient plasmolysis of ...

    The same electronic balance should be used to keep the same level of accuracy for weighing all the root vegetable cylinders. 7) The same root vegetable should be used to take the cylinders from, as different root vegetables have various solute potentials therefore may cause variations within the results.

  2. Catalyse Investigation

    One limitation of the investigation is the range of pH and temperature that can be measured. In this investigation I will be recording the effect of temperatures of 22�, 30�, 35�, 40� 45�, 50�, 55�, 60�, 70� and 100�C. This means that the rate of reaction between these values can not be distinguished between or evaluated with sufficient accuracy.

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

    However, the factor that I will be testing is to do with the presence of inhibitors or activators. These molecules can interact with an enzyme, either causing the enzyme to work better, or to slow down. There are two types of inhibitors; non-competitive and competitive inhibitors.

  2. An investigation to find the lowest temperature that kills all the yeast cells in ...

    This is known as the enzyme being denatured. So based on this Information the enzymes in yeast will denature after the optimum temperature, which I predict is around 50�C meaning the enzymes needed for the yeast to respire will denature and the yeast will die.

  1. Biology GCSE Definitions

    phospholipids Phosphate end is hydrophilic, fatty acids hydrophobic and so phosphate end will dissolve. Amino acids Have a central carbon bonded to H, an amine and carboxylic group. Last group is the R-group differs in each amino acid. 20 possibilities Join to other amino acids by condensation reactions between -OH

  2. To find out how the rate of reaction of yeast can be increased

    In my investigation I will be using the enzyme called zymase but this is an example of the lock and key theory: 1. Each enzyme has an active site into which its substrate molecule fits exactly. This enzyme is amylase, and its active site is just the right size and shape for a starch molecule.

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